VizieR Online Data Catalog: 1103 parallaxes and proper motions from URAT (Finch+, 2016)

NASA Astrophysics Data System (ADS)

Finch, C. T.; Zacharias, N.

2016-07-01

We present 1103 trigonometric parallaxes and proper motions from the United States Naval Observatory (USNO) Robotic Astrometric Telescope (URAT) observations taken at the Naval Observatory Flagstaff Station (NOFS). URAT observes through a single filter (part of the dewar window) to provide a fixed bandpass of about 680 to 760nm. The clear aperture of the USNO astrograph is 206mm with a focal length of only 2m. A single exposure covers 28 square degrees with a resolution of 0.9arcsec/pixel. Each of the four large CCDs in the focal plane covers a 2.65 by 2.65 deg area on the sky. Data of all three years of operations (2012 April to 2015 June) at the NOFS are used here for this parallax investigation. For more details about the project, instrument, and observing the reader is referred to the URAT1 paper (Zacharias et al. 2015, cat. I/329). (3 data files).

Changes in Latitude, Changes in Attitude: U.S. Naval Observatory Observations of Solar Eclipses 1869 to the Present

NASA Astrophysics Data System (ADS)

Chizek Frouard, Malynda R.; Towne, Linda; Kaplan, George H.

2017-01-01

In anticipation of the 2017 August 21 total solar eclipse over the continental United States, the history of U.S. Naval Observatory eclipse observations illustrates the changes in science, technology, and policy over the past 148 years.USNO eclipse observations began in 1869, when staff traveled to Des Moines, Iowa and the Bering Strait to look for intra-mercurial planets and to observe the solar corona. During the golden age of eclipse expeditions, the USNO officially participated in a dozen expeditions between 1869 and 1929. Seven of these expeditions were to US locations: 1869 in Iowa; 1878 in Colorado, Wyoming, and Texas; 1880 in California; 1900 in Georgia and North Carolina; 1918 in Oregon; 1923 in California; and 1925 in New York. A total solar eclipse has not traced a path across the width of the continental US since 1918 although several eclipses have passed over parts of the US since then.A few official expeditions occurred later in the 20th century to measure the solar diameter, including a total eclipse in the northwest US in 1979 and an annular eclipse across the southeast in 1984. However, observations began transitioning to mostly personal adventures as individual astronomers arranged unofficial trips.Historians can use the USNO Multi-year Interactive Computer Almanac (MICA) to compute local circumstances for solar eclipses world-wide starting with the annual eclipse of 1800 April 24, which was visible from Alaska. Those looking to make history in 2017 may consult the USNO 2017 August 21 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2017.php).

When Will It Be ...?: U.S. Naval Observatory Sidereal Time and Julian Date Calculators

NASA Astrophysics Data System (ADS)

Chizek Frouard, Malynda R.; Lesniak, Michael V.; Bartlett, Jennifer L.

2017-01-01

Sidereal time and Julian date are two values often used in observational astronomy that can be tedious to calculate. Fortunately, the U.S. Naval Observatory (USNO) has redesigned its on-line Sidereal Time and Julian Date (JD) calculators to provide data through an Application Programming Interface (API). This flexible interface returns dates and times in JavaScript Object Notation (JSON) that can be incorporated into third-party websites or applications.Via the API, Sidereal Time can be obtained for any location on Earth for any date occurring in the current, previous, or subsequent year. Up to 9999 iterations of sidereal time data with intervals from 1 second to 1095 days can be generated, as long as the data doesn’t extend past the date limits. The API provides the Gregorian calendar date and time (in UT1), Greenwich Mean Sidereal Time, Greenwich Apparent Sidereal Time, Local Mean Sidereal Time, Local Apparent Sidereal Time, and the Equation of the Equinoxes.Julian Date can be converted to calendar date, either Julian or Gregorian as appropriate, for any date between JD 0 (January 1, 4713 BCE proleptic Julian) and JD 5373484 (December 31, 9999 CE Gregorian); the reverse calendar date to Julian Date conversion is also available. The calendar date and Julian Date are returned for all API requests; the day of the week is also returned for Julian Date to calendar date conversions.On-line documentation for using all USNO API-enabled calculators, including sample calls, is available (http://aa.usno.navy.mil/data/docs/api.php).For those who prefer using traditional data input forms, Sidereal Time can still be accessed at http://aa.usno.navy.mil/data/docs/siderealtime.php, and the Julian Date Converter at http://aa.usno.navy.mil/data/docs/JulianDate.php.

U.S. Naval Observatory VLBI Analysis Center

NASA Technical Reports Server (NTRS)

Boboltz, David A.; Fey, Alan L.; Geiger, Nicole; Dieck, Chris; Hall, David M.

2013-01-01

This report summarizes the activities of the VLBI Analysis Center at the United States Naval Observatory for the 2012 calendar year. Over the course of the year, Analysis Center personnel continued analysis and timely submission of IVS-R4 databases for distribution to the IVS. During the 2012 calendar year, the USNO VLBI Analysis Center produced two VLBI global solutions designated as usn2012a and usn2012b. Earth orientation parameters (EOP) based on this solution and updated by the latest diurnal (IVS-R1 and IVS-R4) experiments were routinely submitted to the IVS. Sinex files based upon the bi-weekly 24-hour experiments were also submitted to the IVS. During the 2012 calendar year, Analysis Center personnel continued a program to use the Very Long Baseline Array (VLBA) operated by the NRAO for the purpose of measuring UT1-UTC. Routine daily 1-hour duration Intensive observations were initiated using the VLBA antennas at Pie Town, NM and Mauna Kea, HI. High-speed network connections to these two antennas are now routinely used for electronic transfer of VLBI data over the Internet to a USNO point of presence. A total of 270 VLBA Intensive experiments were observed and electronically transferred to and processed at USNO in 2012.

VizieR Online Data Catalog: The PMM USNO-A1.0 Catalogue (Monet 1997)

NASA Astrophysics Data System (ADS)

Monet, D.; Canzian, B.; Harris, H.; Reid, N.; Rhodes, A.; Sell, S.

1998-07-01

USNO-A1.0 is a catalog of 488,006,860 sources whose positions can be used for astrometric references. These sources were detected by the Precision Measuring Machine (PMM) built and operated by the U. S. Naval Observatory Flagstaff Station during the scanning and processing of the Palomar Observatory Sky Survey I (POSS-I) O and E plates, the UK Science Research Council SRC-J survey plates, and the European Southern Observatory ESO-R survey plates. The PMM detects and processes at and beyond the nominal limiting magnitude of these surveys, but the large number of spurious detections requires that a filter be used to eliminate as many as possible. USNO-A's sole inclusion requirement was that there be spatially coincident detections (within a 2 arcsecond radius aperture) on the blue and red survey plate. For field centers of -30 degrees and above, data come from POSS-I plates, while data from field centers of -35 and below come from SRC-J and ESO-R plates. (1 data file).

Implementation and Testing of VLBI Software Correlation at the USNO

NASA Technical Reports Server (NTRS)

Fey, Alan; Ojha, Roopesh; Boboltz, Dave; Geiger, Nicole; Kingham, Kerry; Hall, David; Gaume, Ralph; Johnston, Ken

2010-01-01

The Washington Correlator (WACO) at the U.S. Naval Observatory (USNO) is a dedicated VLBI processor based on dedicated hardware of ASIC design. The WACO is currently over 10 years old and is nearing the end of its expected lifetime. Plans for implementation and testing of software correlation at the USNO are currently being considered. The VLBI correlation process is, by its very nature, well suited to a parallelized computing environment. Commercial off-the-shelf computer hardware has advanced in processing power to the point where software correlation is now both economically and technologically feasible. The advantages of software correlation are manifold but include flexibility, scalability, and easy adaptability to changing environments and requirements. We discuss our experience with and plans for use of software correlation at USNO with emphasis on the use of the DiFX software correlator.

Tools for Implementing the Recent IAU Resolutions: USNO Circular 179 and the NOVAS Software Package

NASA Astrophysics Data System (ADS)

Kaplan, G. H.; Bangert, J. A.

2006-08-01

The resolutions on positional astronomy adopted at the 1997 and 2000 IAU General Assemblies are far-reaching in scope, affecting both the details of various computations and the basic concepts upon which they are built. For many scientists and engineers, applying these recommendations to practical problems is thus doubly challenging. Because the U.S. Naval Observatory (USNO) serves a broad base of users, we have provided two different tools to aid in implementing the resolutions, both of which are intended for the person who is knowledgeable but not necessarily expert in positional astronomy. These tools complement the new material that has been added to The Astronomical Almanac (see paper by Hohenkerk). USNO Circular 179 is a 118-page book that introduces the resolutions to non-specialists. It includes extensive narratives describing the basic concepts as well as compilations of the equations necessary to apply the recommendations. The resolutions have been logically grouped into six main chapters. The Circular is available as a hard-cover book or as a PDF file that can be downloaded from either the USNO/AA web site (http://aa.usno.navy.mil/) or arXiv.org. NOVAS (Naval Observatory Vector Astrometry Subroutines) is a source-code library available in both Fortran and C. It is a long established package with a wide user base that has recently been extensively revised (in version 3.0) to implement the recent IAU resolutions. However, use of NOVAS does not require detailed knowledge of the resolutions, since commonly requested high-level data _ for example, topocentric positions of stars or planets _ are provided in a single call. NOVAS can be downloaded from the USNO/AA web site. Both Circular 179 and NOVAS version 3.0 anticipate IAU adoption of the recommendations of the 2003-2006 working groups on precession and nomenclature.

VizieR Online Data Catalog: Speckle interferometry at USNO. XXI. (Mason+, 2017)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Hartkopf, W. I.; Bredthauer, G.; Ferguson, E. W.; Finch, C. T.; Kilian, C. M.; Rafferty, T. J.; Ragan, T. J.; Wieder, G. D.

2017-06-01

This is the twenty-first in this series of papers and covers the period from 2015 January 13 through 2015 December 19. The results of 2408 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. (3 data files).

Test results of the STI GPS time transfer receiver

NASA Technical Reports Server (NTRS)

Hall, D. L.; Handlan, J.; Wheeler, P.

1983-01-01

Global time transfer, or synchronization, between a user clock and USNO UTC time can be performed using the Global Positioning System (GPS), and commercially available time transfer receivers. This paper presents the test results of time transfer using the GPS system and a Stanford Telecommunications, Inc. (STI) Time Transfer System (TTS) Model 502. Tests at the GPS Master Control Site (MCS) in Vandenburg, California and at the United States Naval Observatory (USNO) in Washington, D.C. are described. An overview of GPS, and the STI TTS 502 is presented. A discussion of the time transfer process and test concepts is included.

VizieR Online Data Catalog: RASS-6dFGS catalogue (Mahony+, 2010)

NASA Astrophysics Data System (ADS)

Mahony, E. K.; Croom, S. M.; Boyle, B. J.; Edge, A. C.; Mauch, T.; Sadler, E. M.

2014-09-01

Objects were selected such that the dominant source of X-ray emission originates from an AGN. The target list was selected from the southern sources (δ<=0°) of the RBSC, a total of 9578 sources. Sources were then checked for optical identifications via a visual inspection process using Digitized Sky Survey (DSS) images. The majority of the optical positions were taken from the United States Naval Observatory (USNO) data base, with the remainder taken from either the Automated Plate Measuring (APM) or DSS catalogues. Positions from these latter catalogues were used when the USNO appeared to give an incorrect position according to the DSS images. Optical magnitudes were taken from the USNO-A2.0 catalogue (Monet 1998, Cat. I/252). (2 data files).

The likely optical counterpart of X-ray transient KS 1731-260

NASA Astrophysics Data System (ADS)

Wijnands, Rudy; Groot, Paul J.; Miller, Jon J.; Markwardt, Craig; Lewin, Walter H. G.; van der Klis, Michiel

2001-07-01

During our 27 March 2001 Chandra observation of the neutron star X-ray transient KS 1731-260, two X-ray sources were detected (Wijnands et al. 2001, ApJL submitted, astro-ph/0107380). One of those sources is very likely a star in the USNO A2.0 optical catalog (Monet et al. 1998, USNO-SA2.0, U.S. Naval Observatory, Washington DC) and in the Two Micron All Sky Survey (2MASS) point source catalog with a position (from 2MASS) of R.A = 17h34m12.70s, Dec. -26d05m48.4s (+/- 0.2 arcseconds).

Naval Observatory Vector Astrometry Software (NOVAS) Version 3.1, Introducing a Python Edition

NASA Astrophysics Data System (ADS)

Barron, Eric G.; Kaplan, G. H.; Bangert, J.; Bartlett, J. L.; Puatua, W.; Harris, W.; Barrett, P.

2011-01-01

The Naval Observatory Vector Astrometry Software (NOVAS) is a source-code library that provides common astrometric quantities and transformations. NOVAS calculations are accurate at the sub-milliarcsecond level. The library can supply, in one or two subroutine or function calls, the instantaneous celestial position of any star or planet in a variety of coordinate systems. NOVAS also provides access to all of the building blocks that go into such computations. NOVAS Version 3.1 introduces a Python edition alongside the Fortran and C editions. The Python edition uses the computational code from the C edition and, currently, mimics the function calls of the C edition. Future versions will expand the functionality of the Python edition to harness the object-oriented nature of the Python language, and will implement the ability to handle large quantities of objects or observers using the array functionality in NumPy (a third-party scientific package for Python). NOVAS 3.1 also adds a module to transform GCRS vectors to the ITRS; the ITRS to GCRS transformation was already provided in NOVAS 3.0. The module that corrects an ITRS vector for polar motion has been modified to undo that correction upon demand. In the C edition, the ephemeris-access functions have been revised for use on 64-bit systems and for improved performance in general. NOVAS, including documentation, is available from the USNO website (http://www.usno.navy.mil/USNO/astronomical-applications/software-products/novas).

GPS Monitor Station Upgrade Program at the Naval Research Laboratory

NASA Technical Reports Server (NTRS)

Galysh, Ivan J.; Craig, Dwin M.

1996-01-01

One of the measurements made by the Global Positioning System (GPS) monitor stations is to measure the continuous pseudo-range of all the passing GPS satellites. The pseudo-range contains GPS and monitor station clock errors as well as GPS satellite navigation errors. Currently the time at the GPS monitor station is obtained from the GPS constellation and has an inherent inaccuracy as a result. Improved timing accuracy at the GPS monitoring stations will improve GPS performance. The US Naval Research Laboratory (NRL) is developing hardware and software for the GPS monitor station upgrade program to improve the monitor station clock accuracy. This upgrade will allow a method independent of the GPS satellite constellation of measuring and correcting monitor station time to US Naval Observatory (USNO) time. THe hardware consists of a high performance atomic cesium frequency standard (CFS) and a computer which is used to ensemble the CFS with the two CFS's currently located at the monitor station by use of a dual-mixer system. The dual-mixer system achieves phase measurements between the high-performance CFS and the existing monitor station CFS's to within 400 femtoseconds. Time transfer between USNO and a given monitor station is achieved via a two way satellite time transfer modem. The computer at the monitor station disciplines the CFS based on a comparison of one pulse per second sent from the master site at USNO. The monitor station computer is also used to perform housekeeping functions, as well as recording the health status of all three CFS's. This information is sent to the USNO through the time transfer modem. Laboratory time synchronization results in the sub nanosecond range have been observed and the ability to maintain the monitor station CFS frequency to within 3.0 x 10 (sup minus 14) of the master site at USNO.

GPS Timing Performance

DTIC Science & Technology

2014-01-01

termed the Galileo -GPS Time Offset (GGTO), and it will be Type 35 in the GPS CNAV message. Knowledge of the GGTO makes it possible for a properly...U.S. Naval Observatory (USNO) [1]. Interoperability with Galileo , and perhaps someday with other Global Navigation Satellite Systems (GNSS), is to...Interoperability with Galileo , and perhaps someday with other Global Navigation Satellite Systems (GNSS), is to be established through transmission of the

When Will It Be …?: U.S. Naval Observatory Religious Calendar Computers Expanded

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Chizek Frouard, Malynda; Ziegler, Cross; Lesniak, Michael V.

2017-01-01

Reflecting increasing sensitivity to differing religious practices, the U.S. Naval Observatory (USNO) has expanded its on-line calendar resources to compute additional religious dates for specific years via an Application Programming Interface (API). This flexible method now identifies Christian, Islamic, and Jewish events in JavaScript Object Notation (JSON) that anyone can use.Selected Christian Observances (http://aa.usno.navy.mil/data/docs/easter.php) returns dates of eight events for years after 1582 C.E. (A.D. 1582): Ash Wednesday, Palm Sunday, Good Friday, Easter, Ascension, Whit Sunday, Trinity Sunday, and the first Sunday of Advent. The determination of Easter, a moveable feast, uses the method of western Christian churches.Selected Islamic Observances (http://aa.usno.navy.mil/data/docs/islamic.php) returns approximate Gregorian dates of three events for years after 1582 C.E. (A.H. 990) and Julian dates for 622-1582 C.E. (A.H. 1-990) along with the corresponding Islamic year (anno Hegirae). Ramadân, Shawwál, and the Islamic year begin at sunset on the preceding Gregorian or Julian date. For planning purposes, the determination of these dates uses a tabular calendar; in practice, observation of the appropriate waxing crescent Moon determines the actual date, which may vary.Selected Jewish Observances (http://aa.usno.navy.mil/data/docs/passover.php) returns Gregorian dates of six events for years after 1582 C.E. (A.M. 5342) and Julian dates for the years 360-1582 C.E. (A.M. 4120-5342) along with the corresponding Jewish year (anno Mundi). Passover, Shavuot, Rosh Hashanah, Yom Kippur, and Hanukkah begin at sunset on the preceding Gregorian or Julian date.On-line documentation for using the API-enabled calendar computers, including sample calls, is available (http://aa.usno.navy.mil/data/docs/api.php). The webpage also describes how to use the API with the Complete Sun and Moon Data for One Day, Phases of the Moon, Solar Eclipse Computer, Day and Night Across the Earth, Apparent Disk of a Solar System Object, Julian Date Conversion, and Sidereal Time services.Introduction to Calendars (http://aa.usno.navy.mil/faq/docs/calendars.php) provides an overview of the topic and links to additional resources.

When Will It Be …?: U.S. Naval Observatory Calendar Computers

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Chizek Frouard, Malynda; Lesniak, Michael V.

2016-06-01

Sensitivity to religious calendars is increasingly expected when planning activities. Consequently, the U.S. Naval Observatory (USNO) has redesigned its on-line calendar resources to allow the computation of select religious dates for specific years via an application programming interface (API). This flexible interface returns dates in JavaScript Object Notation (JSON) that can be incorporated into third-party websites or applications. Currently, the services compute Christian, Islamic, and Jewish events.The “Dates of Ash Wednesday and Easter” service (http://aa.usno.navy.mil/data/docs/easter.php) returns the dates of these two events for years after 1582 C.E. (1582 A.D.) The method of the western Christian churches is used to determined when Easter, a moveable feast, occurs.The “Dates of Islamic New Year and Ramadan” service (http://aa.usno.navy.mil/data/docs/islamic.php) returns the approximate Gregorian dates of these two events for years after 1582 C.E. (990 A.H.) and Julian dates are computed for the years 622-1582 C.E. (1-990 A.H.). The appropriate year in the Islamic calendar (anno Hegira) is also provided. Each event begins at 6 P.M. or sunset on the preceding day. These events are computed using a tabular calendar for planning purposes; in practice, the actual event is determined by observation of the appropriate new Moon.The “First Day of Passover” service (http://aa.usno.navy.mil/data/docs/passover.php) returns the Gregorian date corresponding to Nisan 15 for years after 1582 C.E. (5342 A.M.) and Julian dates are computed for the years 360-1582 C.E. (4120-5342 A.M.). The appropriate year in the Jewish calendar (anno Mundi) is also provided. Passover begins at 6 P.M. or sunset on the preceding day.On-line documentation for using the API-enabled calendar computers, including sample calls, is available (http://aa.usno.navy.mil/data/docs/api.php). The same web page also describes how to reach the Complete Sun and Moon Data for One Day, Phases of the Moon, Solar Eclipse Computer, Day and Night Across the Earth, and Apparent Disk of a Solar System Object services using API calls.An “Introduction to Calendars” (http://aa.usno.navy.mil/faq/docs/calendars.php) provides an overview of the topic and links to additional resources.

USNO Master Clock - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Master Clock USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info USNO Master Clock clock vault The USNO Master Clock is the

USNO Image and Catalog Archive Server - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astrometry › Optical/IR Products › USNO Image and Catalog Archive Server USNO Logo USNO Navigation Optical/IR Products NOMAD UCAC URAT USNO-B1.0 Double Stars Solar System Link Disclaimer This is an official U.S. Navy web site. Security & Privacy Policy Veterans Crisis

There's An App For That: Planning Ahead for the Solar Eclipse in August 2017

NASA Astrophysics Data System (ADS)

Chizek Frouard, Malynda R.; Lesniak, Michael V.; Bell, Steve

2017-01-01

With the total solar eclipse of 2017 August 21 over the continental United States approaching, the U.S. Naval Observatory (USNO) on-line Solar Eclipse Computer can now be accessed via an Android application, available on Google Play.Over the course of the eclipse, as viewed from a specific site, several events may be visible: the beginning and ending of the eclipse (first and fourth contacts), the beginning and ending of totality (second and third contacts), the moment of maximum eclipse, sunrise, or sunset. For each of these events, the USNO Solar Eclipse 2017 Android application reports the time, Sun's altitude and azimuth, and the event's position and vertex angles. The app also lists the duration of the total phase, the duration of the eclipse, the magnitude of the eclipse, and the percent of the Sun obscured for a particular eclipse site.All of the data available in the app comes from the flexible USNO Solar Eclipse Computer Application Programming Interface (API), which produces JavaScript Object Notation (JSON) that can be incorporated into third-party Web sites or custom applications. Additional information is available in the on-line documentation (http://aa.usno.navy.mil/data/docs/api.php).For those who prefer using a traditional data input form, the local circumstances can still be requested at http://aa.usno.navy.mil/data/docs/SolarEclipses.php.In addition the 2017 August 21 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2017.php) consolidates all of the USNO resources for this event, including a Google Map view of the eclipse track designed by Her Majesty's Nautical Almanac Office (HMNAO).Looking further ahead, a 2024 April 8 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2024.php) is also available.

USNO CCD Astrograph Catalog (UCAC) - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astrometry › Optical/IR Products › UCAC USNO Logo USNO Navigation Optical/IR Products NOMAD UCAC URAT USNO-B1.0 Double Stars Solar System Bodies USNO Image and Catalog 2MASS near-IR photometry (as in previous releases) UCAC4 now includes APASS 5-band photometry. The APASS

When Will It Be... USNO Seasons and Apsides Calculator

NASA Astrophysics Data System (ADS)

Chizek Frouard, Malynda; Bartlett, Jennifer Lynn

2018-01-01

The turning of the Earth’s seasons (solstices and equinoxes) and apsides (perihelions and aphelions) are times often used in observational astronomy and also of interest to the public. To avoid tedious calculations, the U.S. Naval Observatory (USNO) has developed an on-line interactive calculator, Earth’s Seasons and Apsides to provide information about events between 1600 and 2200. The new data service uses an Application Programming Interface (API), which returns values in JavaScript Object Notation (JSON) that can be incorporated into third-party websites or applications. For a requested year, the Earth’s Seasons and Apsides API provides the Gregorian calendar date and time of the Vernal Equinox, Summer Solstice, Autumnal Equinox, Winter Solstice, Aphelion, and Perihelion. The user may specify the time zone for their results, including the optional addition of U.S. daylight saving time for years after 1966.On-line documentation for using the API-enabled Earth’s Seasons and Apsides is available, including sample calls (http://aa.usno.navy.mil/data/docs/api.php). A traditional forms-based interface is available as well (http://aa.usno.navy.mil/data/docs/EarthSeasons.php). This data service replaces the popular Earth's Seasons: Equinoxes, Solstices, Perihelion, and Aphelion page that provided a static list of events for 2000–2025. The USNO also provides API-enabled data services for Complete Sun and Moon Data for One Day (http://aa.usno.navy.mil/data/docs/RS_OneDay.php), Dates of the Primary Phases of the Moon (http://aa.usno.navy.mil/data/docs/MoonPhase.php), Selected Christian Observances (http://aa.usno.navy.mil/data/docs/easter.php), Selected Islamic Observances (http://aa.usno.navy.mil/data/docs/islamic.php), Selected Jewish Observances (http://aa.usno.navy.mil/data/docs/passover.php), Julian Date Conversion (http://aa.usno.navy.mil/data/docs/JulianDate.php), and Sidereal Time (http://aa.usno.navy.mil/data/docs/siderealtime.php) as well as its Solar Eclipse Computer (http://aa.usno.navy.mil/data/docs/SolarEclipses.php).

Library Collections - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › James M. Gilliss Library › Library Collections USNO Logo USNO Navigation of the James M. Gilliss library include: recently cataloged books, electronic journals, publications

Oceanography - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Oceanography USNO Logo USNO Info Oceanography The following Oceanography components have moved their publicly-available products to http://www.metoc.navy.mil: Naval Oceanography

Preliminary Parallaxes of 40 L and T Dwarfs from the US Naval Observatory Infrared Astronometry Program

NASA Technical Reports Server (NTRS)

Vrba, F. J.; Henden, A. A.; Liginbuhl, C. B.; Guetter, H. H.; Munn, J. A.

2004-01-01

We present preliminary trigonometric parallaxes and proper motions for 22 L dwarfs and 18 T dwarfs measured using the ASTROCAM infrared imager on the US naval Observatory (USNO) 1.55 m Strand Astrometric Reflector. The results presented here are based on observations obtained between 2000 September and 2002 November; about half of the objects have an observational time baseline of t 1:3 yr and half t 2:0 yr. Despite these short time baselines, the astrometric quality is sufficient to produce significant new results, especially for the nearer T dwarfs. Seven objects are in common with the USNO optical CCD parallax program for quality control and seven in common with the European Southern Observatory 3.5 m New Technology Telescope parallax program. We compare astrometric quality with both of these programs. Relative to absolute parallax corrections are made by employing Two Micron All Sky Survey and/or Sloan Digital Sky Survey photometry for reference-frame stars. We combine USNO infrared and optical parallaxes with the best available California Institute of Technology (CIT) system photometry to determine MJ , MH, and MK values for 37 L dwarfs between spectral types L0 and L8 and 19 T dwarfs between spectral types T0.5 and T8 and present selected absolute magnitude versus spectral type and color diagrams, based on these results. Luminosities and temperatures are estimated for these objects. Of special interest are the distances of several objects that are at or near the L-T dwarf boundary so that this important transition can be better understood. The previously reported early to mid T dwarf luminosity excess is clearly confirmed and found to be present at J, H, and K. The large number of objects that populate this luminosity-excess region indicate that it cannot be due entirely to selection effects. The T dwarf sequence is extended to MJ 16:9 by 2MASS J041519 0935, which, at d 5:74 pc, is found to be the lluminous LOG (L=L )pa

For DoD Users - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astronomical Applications › For DoD Users USNO Logo USNO Navigation Data Services Astronomical Information Center Almanacs and Other Publications Software Products For DoD Users

VLBI-based Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › VLBI-based Products USNO Logo USNO Navigation Earth determine Earth Orientation Parameters (EOP) is Very Long Baseline Interferometry (VLBI). USNO provides both

GPS timing products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › GPS USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info GPS timing products USNO monitors the GPS constellation and provides

The First US Naval Observatory CCD Astrograph Catalog

NASA Astrophysics Data System (ADS)

Zacharias, N.; Urban, S. E.; Zacharias, M. I.; Hall, D. M.; Wycoff, G. L.; Rafferty, T. J.; Germain, M. E.; Holdenried, E. R.; Pohlman, J. W.; Gauss, F. S.; Monet, D. G.; Winter, L.

2000-10-01

The USNO CCD Astrograph (UCA) started an astrometric survey in 1998 February at Cerro Tololo, Chile. This first, preliminary catalog (UCAC1) includes data taken up to 1999 November with about 80% of the Southern Hemisphere covered. Observing continues, and full sky coverage is expected by mid-2003 after moving the instrument to a Northern Hemisphere site in early 2001. The survey is performed in a single bandpass (579-642 nm), a twofold overlap pattern of fields, and with a long and a short exposure on each field. Stars in the magnitude range 10-14 have positional precisions of <=20 mas. At the limiting magnitude of R~16 mag, the positional precision is 70 mas. The UCAC aims at a density (stars per square degree) larger than that of the Guide Star Catalog (GSC) with a positional accuracy similar to Tycho. The UCAC program is a major step toward a high-precision densification of the optical reference frame in the post-Hipparcos era, and the first stage, the UCAC1 contains over 27 million stars. Preliminary proper motions are included, which were derived from Tycho-2, Hipparcos, and ground-based transit circle and photographic surveys for the bright stars (V<=12.5 mag) and the USNO A2.0 for the fainter stars. The accuracy of the proper motions varies widely, from 1 to over 15 mas yr-1. The UCAC1 is available on CD-ROM from the US Naval Observatory.

Telephone Time - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Telephone Time USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Telephone Time USNO provides both voice announcements of the

Obituary: Julena Steinheider Duncombe, 1911-2003

NASA Astrophysics Data System (ADS)

Seidelmann, P. Kenneth

2004-12-01

Julena Steinheider Duncombe died on 13 September 2003, just eight days before her 92nd birthday. Julena Steinheider was born September 21, 1911 on a farm in Dorchester, Nebraska and grew up in Goehner, Nebraska. Her parents were Frederick and Ella Beenders Steinheider, and she had four brothers. She began college at the age of 17 and graduated at 21 from Doane College in Crete, Nebraska with a major in mathematics and a minor in astronomy. She started teaching in a one-room schoolhouse, where, with assistance from her family, she started possibly the first school lunch program by fixing lunches on the schoolhouse stove to provide food for children who only had popcorn to eat. Then she taught in Minatare and Scotts Bluff, Nebraska, and in a Japanese Relocation Camp in Wyoming. In 1945 she moved to Washington DC to begin working at the US Naval Observatory (USNO). She was the first woman observer on the 6-inch transit circle. She worked as an observer and mathematician reducing and analyzing observations of the Sun, Moon, planets, and stars. At the Naval Observatory she met Raynor Duncombe and married him in Goehner, Nebraska, in January 1948. She resigned from the USNO in 1948 to go with her husband to Yale University. At Yale the Duncombes introduced punched card equipment into the Astronomy Department. Ray also took graduate classes and Julie worked on Astrographic Catalog reductions. Upon returning to USNO in 1950 she joined the Nautical Almanac Office. She supervised the punched card operated typewriter to produce tables of positions of celestial bodies for air and sea navigation. With Dorrit Hoffleit she directed the keypunching of over 150 star catalogs, approximating 1.5 million cards. Several thousand errata to the catalogs were discovered and corrected on the cards and tape versions of the catalogs. This activity was the basis for future stellar databases. From 1963 she was responsible for producing the tabular predictions and maps for solar and lunar eclipses, which appeared in the almanacs and special circulars. After 28 years at the U S Naval Observatory she retired in 1973. In 1975 the Duncombes moved to Austin, Texas. There she supported Ray, who was executive editor of Celestial Mechanics, serving as associate editor of the journal. Throughout their lives in Washington and Austin the Duncombes were gracious hosts for overnight guests and for dinner parties. Julie was very experienced at giving both small and large dinner parties for foreign visitors, USNO staff, graduate students and others. They also hosted people at their mountain house in Highlands, NC. Julie Duncombe was a fellow of the American Association for the Advancement of Science, a member of the American Astronomical Society, Division on Dynamical Astronomy, American Association of University Women, and the Institute of Navigation. She was a proponent for women having careers in mathematics and science. In 1959 the Department of Labor featured her career at the USNO as an example of what women in Federal Service could accomplish. In her later years she suffered from macular degeneration and Alzheimer's disease. She is survived by her husband of 55 years, Raynor Lockwood Duncombe; stepson Raynor Bailey Duncombe and wife Janice of Middleburg, NY; grandchildren Raynor Luccioni Duncombe and wife Heidi of Charlotte, NC and Christina Luccioni Duncombe of Williamsburg, VA.

The AC 2000.2 Catalogue

NASA Astrophysics Data System (ADS)

Urban, S. E.; Corbin, T. E.; Wycoff, G. L.; Makarov, V. V.; Høg, E.; Fabricius, C.

2001-12-01

For over 100 years, the international project known as the Astrographic Catalogue -- which involved 20 observatories tasked to photograph the sky -- has held an unfulfilled promised of yielding a wealth of astrometric information. This promise was not realized due to the inadequate reductions of the project's plates. However, in 1997 the U.S. Naval Observatory (USNO) completed the reductions of the 22,660 plates. That catalogue, named the AC 2000, contained positions and magnitudes for 4.6 million stars down to about v magnitude 12.5. Due to the early epochs of the data -- averaging 1907 -- and the positional accuracies -- between 150 and 400 milliarcseconds -- the data are extremely valuable in computing proper motions. In 1997, these positions were used to form the proper motions of the ACT Reference Catalogue. In 1999, USNO and Copenhagen University Observatory (CUO) partnered to create the Tycho-2 Catalogue. The CUO group re-analyzed the data from the Tycho experiment on the Hipparcos satellite. The USNO group re-analyzed over 140 positional catalogs which were combined with the expanded Tycho positions from the CUO group to compute the Tycho-2 proper motions. The largest contributor to these proper motions was the re-analyzed Astrographic Catalogue; the latest version being known as the AC 2000.2 Catalogue. There are two major differences between the AC 2000 and the AC 2000.2. First, the reference catalog used in AC 2000.2 was an expanded version of the Astrographic Catalogue Reference Stars that was rigorously derived on the Hipparcos Celestial Reference Frame. The second is that AC 2000.2 contains photometry from Tycho-2, where available. A description of the AC 2000.2 Catalogue, the reduction techniques used, how it compares with the 1997 version, and information on obtaining the data will be presented.

Publications about Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Publications about Products USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center

Software - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Software USNO Logo USNO Navigation Earth Orientation Search databases Auxiliary Software Supporting Software Form Folder Earth Orientation Matrix Calculator

USNO Scientific Colloquia - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You Navigation Tour Information USNO Scientific Colloquia Info USNO Scientific Colloquia Time and Place: Unless departure. Add additional time prior to arriving at the colloquium for issuance of a visitors badge and

The Sky This Week, 2016 March 1 - 8 - Naval Oceanography Portal

Science.gov Websites

submit many observations from different locations throughout the year. This is a great time to start are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 March 1 - 8 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky

Leap Second Announcement - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Leap Second Announcement USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center Publications

Earth Orientation - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation USNO Logo USNO Navigation Earth Orientation Products GPS -based Products VLBI-based Products EO Information Center Publications about Products Software Info Earth

EO Information Center - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Earth Orientation › EO Information Center USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center General Information GPS User Information Frequently Asked Questions Read Me Files Publications about Products Software

Almanacs and Other Publications - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astronomical Applications › Almanacs and Other Publications USNO Logo USNO Navigation Data Services Astronomical Information Center Almanacs and Other Publications Software Products For DoD Users Info Almanacs and Other Publications Annual Astronomical and Navigational Almanacs

The USNO-UKIRT K-band Hemisphere Survey

NASA Astrophysics Data System (ADS)

Dahm, Scott; Bruursema, Justice; Munn, Jeffrey A.; Vrba, Fred J.; Dorland, Bryan; Dye, Simon; Kerr, Tom; Varricatt, Watson; Irwin, Mike; Lawrence, Andy; McLaren, Robert; Hodapp, Klaus; Hasinger, Guenther

2018-01-01

We present initial results from the United States Naval Observatory (USNO) and UKIRT K-band Hemisphere Survey (U2HS), currently underway using the Wide Field Camera (WFCAM) installed on UKIRT on Maunakea. U2HS is a collaborative effort undertaken by USNO, the Institute for Astronomy, University of Hawaii, the Cambridge Astronomy Survey Unit (CASU) and the Wide Field Astronomy Unit (WFAU) in Edinburgh. The principal objective of the U2HS is to provide continuous northern hemisphere K-band coverage over a declination range of δ=0o – +60o by combining over 12,700 deg2 of new imaging with the existing UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS), Galactic Plane Survey (GPS) and Galactic Cluster Survey (GCS). U2HS will achieve a 5-σ point source sensitivity of K~18.4 mag (Vega), over three magnitudes deeper than the Two Micron All Sky Survey (2MASS). In this contribution we discuss survey design, execution, data acquisition and processing, photometric calibration and quality control. The data obtained by the U2HS will be made publicly available through the Wide Field Science Archive (WSA) maintained by the WFAU.

The Sky This Week, 2016 January 19 - 26 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 January 19 - 26 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 January 19 - 26 Info The Sky This Week, 2016 January 19 - 26 See all the bright planets

The Sky This Week, 2016 April 19 - 26 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 April 19 - 26 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 April 19 - 26 Info The Sky This Week, 2016 April 19 - 26 A bright and speedy star

The Sky This Week, 2015 December 8 - 15 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2015 December 8 - 15 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2015 December 8 - 15 Info The Sky This Week, 2015 December 8 - 15 The year's best meteor

The Sky This Week, 2016 February 16 - 23 - Naval Oceanography Portal

Science.gov Websites

very nice pentagon shape. The southernmost star in the pentagon, Al Nath, is "shared" as the are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 February 16 - 23 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky

Astrometry Information Center - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astrometry › Astrometry Information Center USNO Logo USNO Navigation Optical/IR Products VLBI-based Products Astrometry Information Center Catalog Information Double Star Information VLBI-based Product Information Info Astrometry Information Center Within the astrometry

Two-way Satellite Time Transfer - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › TWSTT USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT What is TWSTT? Operational Services Calibration Services Precision Telephone Time NTP Info

The Sky This Week, 2016 March 15 - 23 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 March 15 - 23 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 March 15 - 23 Info The Sky This Week, 2016 March 15 - 23 The equinox and the calendar

The Sky This Week, 2016 January 12 - 19 - Naval Oceanography Portal

Science.gov Websites

would be very different in that case! The planets are now beginning to span more of the night. Leading are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 January 12 - 19 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky

The Sky This Week, 2016 January 5 - 12 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 January 5 - 12 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 January 5 - 12 Info The Sky This Week, 2016 January 5 - 12 Count the stars in Orion for

Obituary: Geoffrey Gardner Douglass, 1942-2005

NASA Astrophysics Data System (ADS)

Mason, Brian D.; Hartkopf, William; Corbin, Thomas

2005-12-01

Geoffrey Gardner Douglass passed away on 15 February 2005, following a long illness. Geoff was born 11 June 1942 in Rocky River, Ohio, and grew up there with a passion for science, theatre, and pets. He attended the nearby Case Institute of Technology (Cleveland, Ohio) before coming to the U.S. Naval Observatory on 28 April 1967. He worked at the USNO for over 30 years, until his retirement in January 1999. He was involved in the observing and measurement of parallax and double star plates on the SAMM and MANN measuring engines, and was stationed at Blenheim, New Zealand from 1985-1988 working at the Black Birch site on the Twin Astrograph Telescope. While there he and his wife Doris travelled extensively throughout New Zealand and Australia, He later worked with an early iteration of the USNO StarScan measuring machine. However, most of his work involved observations of visual double stars with the USNO 26-inch Clark Refractor, collaborating with F.J. ("Jerry") Josties on the photographic program in the late 1960s to the development of the USNO's speckle interferometry program throughout the 1990s. Geoff collaborated closely with Charles Worley from 1968 until Charles's death in December 1997, writing much of the double star software and assisting in the production of the USNO's double star catalogs. This was a period of transition, when some 200,000 punch cards of the Lick IDS (Index Catalog of Double Stars) were transferred from Lick Observatory to the USNO, then converted to magnetic tape. This ultimately resulted in the 1984 WDS catalog (currently maintained online). It was often joked that the "W" and "D" in the WDS (officially the "Washington Double Star" catalog) really stood for "Worley" and "Douglass." The "Curmudgeon" and the "Dour Scot" were a team for nearly thirty years. Geoff's first observation, of BU 442, was made 2 June 1967 with the USNO double star (photographic) camera, and his last, STF 342, was made on 28 November 1998 with the USNO speckle camera on the 26-inch refractor. In between he was an active collaborator and observer on these two different programs which, during his tenure at USNO, contributed over 18,000 measured positions to the WDS. While he discovered no new pairs, this was never his interest. He was much more interested in following up known systems and characterizing their motions to improve the catalog. During his long illness, even while at Cameron Glen Nursing Home, he continued to have an interest in the activities at the USNO and continued to be sought out for his knowledge on the instrumentation of the speckle camera. Late in 2004, when he was consulted on the location of a set of visual measures made in the early 1990s, his comment was that "every measure counted." During his last year at the observatory he oversaw the publication of over 10,000 speckle observations, and guided the recently hired Brian Mason (Charles's replacement) in the management of the double star program. Geoff battled illness for many years. He was a symbol of the worthiness of organ donation, living for some two decades following a kidney transplant, before succumbing to complications following the failure of the transplanted kidney. Geoff is survived by his wife, Doris, with whom he shared a love of cats and classical music. They touched many lives both at the Observatory and at their church, Graham Road United Methodist, where both he and Doris were active leaders in many ministries. Geoff was very passionate about his religious views, going so far as to name his old computer ``crux.'' Geoff will be sorely missed by his many friends and colleagues.

The first US Naval Observatory CCD Astrograph Catalog

NASA Astrophysics Data System (ADS)

Germain, M. E.; Zacharias, N.; Urban, S. E.; Rafferty, T. J.; Holdenried, E. R.; Zacharias, M. I.; Hall, D. M.; Wycoff, G. L.; Monet, D. G.

2000-05-01

The USNO CCD Astrograph Catalog (UCAC) project is a high precision, astrometric survey of stars having R magnitudes between 7th and 16th. The positional accuracy is 20 mas for stars between 9th and 14th, and 70 mas for fainter stars. This gives a density (stars per square degree) higher than that of the Guide Star Catalog (GSC), with an improvement in positional accuracy of about a factor of ten. Observations began in January 1998 at Cerro Tololo Inter--American Observatory (CTIO) using a five-element 0.2 meter astrograph equipped with a 4k by 4k CCD. The instrument will be moved north in early 2001, and full sky coverage is expected by early 2003. A preliminary catalog (UCAC1) of positions and proper motions of 27 million stars has been constructed which is available on CD-ROM from USNO. Observations between 13 Feb 1998 and 07 Nov 1999 are included with a total of over 79,000 CCD frames covering 80% of the Southern Hemisphere. The catalog is on the International Celestial Reference System (ICRS), which is consistent with J2000. Proper motions of bright stars (V <= 12.5) were derived using a combination of ground-based astrometric catalogs, Hipparcos, and Tycho-2 positions, giving a typical error of 3 mas/yr. For the fainter stars the USNO A2.0 (Monet, 1998) was used as first epoch, with typical proper motion errors of 10 to 15 mas/yr. External comparisons with Tycho-2 and the Yale Southern Proper Motion (SPM) 2.0 data reveal systematic errors to be only on the 10 mas level.

Optical/IR Products - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › Astrometry › Optical/IR Products USNO Logo USNO Navigation Optical/IR VLBI-based Products Astrometry Information Center Info Optical/IR Products Access to astrometric 2012. A poster paper describing the progress of URAT was presented at the April 2014 DDA meeting in

Web-Based Time Synchronization - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Display Clocks USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Web-Based Time Synchronization Web time displays from the

Network Time Protocol - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › NTP USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Eastern TZ Mountain TZ DoD Customers Info Network Time Protocol Network

The USNO 26'' Clark Refractor; From Visual Observations to Speckle Interferometry

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Mason, B. D.; Hartkopf, W. I.

2011-01-01

Before addressing queries about how and what to preserve among astronomical devices, the question of what constitutes a historic instrument must be considered. Certainly, the lenses are the defining feature of a Clark refractor. Since 1867, when Newcomb inquired about the possibility of obtaining a great glass from Alvan Clark & Sons, the U.S. Naval Observatory 26-in (66-cm) equatorial has evolved in response to improvements in technology and changes in its observing program. After two major overhauls, only the objective remains of the equipment originally installed by the Clarks in 1873 at the old Observatory site in Foggy Bottom. However, the telescope retains its reputation as a historic Clark refractor. The USNO telescope was briefly renowned as the largest refractor in the world; the second of five such achievements by the Clarks. Through it, Hall first detected the moons of Mars in 1877. However, by that time, the Clarks had already refigured the flint glass. Hall and Gardiner had also altered the drive mechanism. When the USNO moved to its present Georgetown Heights location in 1893, the great equatorial was refurbished with its original Clark optics installed on a more robust Warner & Swasey mount. Peters eventually incorporated discarded parts from the original mounting into his photographic telescopes during the first half of the 20th century. The 26'' refractor underwent further modernization in the early 1960s to facilitate the xy-slide of a Hertzsprung-style photographic double star camera. In 1965, the objective was disassembled for cleaning and reassembled with new spacers. The most recent maintenance included re-wiring and replacing several motors and the hand paddles. Originally designed as a visual instrument, the USNO 26'' Clark refractor now hosts a speckle interferometer for its current double star program. Despite continuing modifications, this telescope remains a fine example of the optician's art.

Library History - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › James M. Gilliss Library › Library History USNO Logo USNO Navigation , Artwork, Objects Library History Library Dedication The Story Behind the Seal Additional Resources Info Library History lib15b.jpg There is a lot of history in the Library; over the years it has served as not

A proposed time transfer experiment between the USA and the South Pacific

NASA Technical Reports Server (NTRS)

Luck, John; Dunkley, John; Armstrong, Tim; Gifford, Guy A.; Landis, Paul; Rasmussen, Scott; Wheeler, Paul J.; Bartholomew, Thomas R.; Stein, Samuel R.

1992-01-01

Described here are the concept, architecture and preliminary details of an experiment directed towards providing continuous Ultra High Precision (UHP) time transfer between Washington, DC; Salisbury, SA Australia; Orroral Valley, ACT Australia; and Lower Hutt, New Zealand. A proposed method of distributing UTC(USNO) at a high level of precision to passive users over a broad area of the South Pacific is described. The concept is based on active two-way satellite time transfer from the United States Naval Observatory (USNO) to the proposed USNO Master Clock West (MCW) in Wahiwa, HI at the 1 nanosecond level using active satellite two-way time transfer augmented by Precise Positioning Service (PPS) of the Global Positioning System (GPS). MCW would act as an intermediate transfer/reference station, again linked to Salisbury at the 1 nanosecond level using active satellite two-way time transfer augmented by PPS GPS. From this point, time would be distributed within the region by two methods. The first is an existing TV line sync system using an Australian communications satellite (AUSSAT K1) which is useful to the 20 nanosecond level. The second approach is RF ranging and multilateration between Salisbury, Orroral Observatory, Lower Hutt and the AUSSAT B1 and B2 to be launched in 1992. Orroral Observatory will provide precise laser ranging to the AUSSAT B1/B2 retro reflectors which will reduce ephemeris related time transfer errors to below 1 nanosecond. The corrected position will be transmitted by both the time transfer modem and the existing TV line sync dissemination process. Multilateration has the advantage of being an all weather approach and when used with the laser ranging technique will provide a precise measurement of the propagation path delays. This will result in time transfer performance levels on the order of 10 nanoseconds to passive users in both Australia and New Zealand.

Astronomy - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Astronomy USNO Logo USNO Astronomical Applications AA Data Services Astronomical Optical/IR Products VLBI-based Products Astrometry Information Center Info Astronomy The Sky This Week a

Solar Eclipse Computer API: Planning Ahead for August 2017

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Chizek Frouard, Malynda; Lesniak, Michael V.; Bell, Steve

2016-01-01

With the total solar eclipse of 2017 August 21 over the continental United States approaching, the U.S. Naval Observatory (USNO) on-line Solar Eclipse Computer can now be accessed via an application programming interface (API). This flexible interface returns local circumstances for any solar eclipse in JavaScript Object Notation (JSON) that can be incorporated into third-party Web sites or applications. For a given year, it can also return a list of solar eclipses that can be used to build a more specific request for local circumstances. Over the course of a particular eclipse as viewed from a specific site, several events may be visible: the beginning and ending of the eclipse (first and fourth contacts), the beginning and ending of totality (second and third contacts), the moment of maximum eclipse, sunrise, or sunset. For each of these events, the USNO Solar Eclipse Computer reports the time, Sun's altitude and azimuth, and the event's position and vertex angles. The computer also reports the duration of the total phase, the duration of the eclipse, the magnitude of the eclipse, and the percent of the Sun obscured for a particular eclipse site. On-line documentation for using the API-enabled Solar Eclipse Computer, including sample calls, is available (http://aa.usno.navy.mil/data/docs/api.php). The same Web page also describes how to reach the Complete Sun and Moon Data for One Day, Phases of the Moon, Day and Night Across the Earth, and Apparent Disk of a Solar System Object services using API calls.For those who prefer using a traditional data input form, local circumstances can still be requested that way at http://aa.usno.navy.mil/data/docs/SolarEclipses.php. In addition, the 2017 August 21 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2017.php) consolidates all of the USNO resources for this event, including a Google Map view of the eclipse track designed by Her Majesty's Nautical Almanac Office (HMNAO). Looking further ahead, a 2024 April 8 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2024.php) is also available.

Loran-C time management

NASA Technical Reports Server (NTRS)

Justice, Charles; Mason, Norm; Taggart, Doug

1994-01-01

As of 1 Oct. 1993, the US Coast Guard (USCG) supports and operates fifteen Loran-C chains. With the introduction of the Global Positioning Systems (GPS) and the termination of the Department of Defense (DOD) overseas need for Loran-C, the USCG will cease operating the three remaining overseas chains by 31 Dec. 1994. Following this date, the USCG Loran-C system will consist of twelve chains. Since 1971, management of time synchronization of the Loran-C system has been conducted under a Memorandum of Agreement between the US Naval Observatory (USNO) and the USCG. The requirement to maintain synchronization with Coordinated Universal Time (UTC) was initially specified as +/- 25 microseconds. This tolerance was rapidly lowered to +/- 2.5 microseconds in 1974. To manage this synchronization requirement, the USCG incorporated administrative practices which kept the USNO appraised of all aspects of the master timing path. This included procedures for responding to timing path failures, timing adjustments, and time steps. Conducting these aspects of time synchronization depended on message traffic between the various master stations and the USNO. To determine clock adjustment the USCG relied upon the USNO's Series 4 and 100 updates so that the characteristics of the master clock could be plotted and controls appropriately applied. In 1987, Public Law 100-223, under the Airport and Airway Improvement Act Amendment, reduced the synchronization tolerance to approximately 100 nanoseconds for chains serving the National Airspace System (NAS). This action caused changes in the previous administrative procedures and techniques. The actions taken by the USCG to meet the requirements of this law are presented.

Tour Information for USNO Washington DC - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You Week, 2018 May 22 - 29 More... Naval Meteorology and Oceanography Command, 1100 Balch Blvd, Stennis

Linear quadratic stochastic control of atomic hydrogen masers.

PubMed

Koppang, P; Leland, R

1999-01-01

Data are given showing the results of using the linear quadratic Gaussian (LQG) technique to steer remote hydrogen masers to Coordinated Universal Time (UTC) as given by the United States Naval Observatory (USNO) via two-way satellite time transfer and the Global Positioning System (GPS). Data also are shown from the results of steering a hydrogen maser to the real-time USNO mean. A general overview of the theory behind the LQG technique also is given. The LQG control is a technique that uses Kalman filtering to estimate time and frequency errors used as input into a control calculation. A discrete frequency steer is calculated by minimizing a quadratic cost function that is dependent on both the time and frequency errors and the control effort. Different penalties, chosen by the designer, are assessed by the controller as the time and frequency errors and control effort vary from zero. With this feature, controllers can be designed to force the time and frequency differences between two standards to zero, either more or less aggressively depending on the application.

Meteorology/Oceanography Help - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Help › Meteorology/Oceanography Help USNO Logo USNO Info Meteorology/Oceanography Help Send an e-mail regarding meteorology or oceanography products. Privacy Advisory Your E-Mail

Astronomy Help - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Help › Astronomy Help USNO Logo USNO Info Astronomy Help Send an e-mail regarding Astronomy related products. Please choose from the topical menu below. Privacy Advisory Your E-Mail Address

Earth Orientation Help - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Help › Earth Orientation Help USNO Logo USNO Info Earth Orientation Help Send an e-mail regarding Earth Orientation products. Privacy Advisory Your E-Mail Address Subject ■ Select

Time Help - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Help › Time Help USNO Logo USNO Info Time Help Send in a request for help on our timing products. Privacy Advisory Your E-Mail Address Subject General Time Inquiries GPS TWSTT NTP

THE THIRD US NAVAL OBSERVATORY CCD ASTROGRAPH CATALOG (UCAC3)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zacharias, N.; Finch, C.; Wycoff, G.

2010-06-15

The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3, was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8-16 mag. Current epoch positions are obtained from the observations with the 20 cm aperture USNO Astrograph's 'red lens', equipped with a 4k x 4k CCD. Proper motions are derived by combining these observations with over 140 ground- and space-based catalogs, including Hipparcos/Tycho and the AC2000.2, as well as unpublished measuresmore » of over 5000 plates from other astrographs. For most of the faint stars in the southern hemisphere, the Yale/San Juan first epoch plates from the Southern Proper Motion (SPM) program (YSJ1) form the basis for proper motions. These data are supplemented by all-sky Schmidt plate survey astrometry and photometry obtained from the SuperCOSMOS project, as well as 2MASS near-IR photometry. Major differences of UCAC3 data as compared with UCAC2 include a completely new raw data reduction with improved control over systematic errors in positions, significantly improved photometry, slightly deeper limiting magnitude, coverage of the north pole region, greater completeness by inclusion of double stars, and weak detections. This of course leads to a catalog which is not as 'clean' as UCAC2 and problem areas are outlined for the user in this paper. The positional accuracy of stars in UCAC3 is about 15-100 mas per coordinate, depending on magnitude, while the errors in proper motions range from 1 to 10 mas yr{sup -1} depending on magnitude and observing history, with a significant improvement over UCAC2 achieved due to the re-reduced SPM data and inclusion of more astrograph plate data unavailable at the time of UCAC2.« less

Naval Observatory Vector Astrometry Software (NOVAS) Version 3.1:Fortran, C, and Python Editions

NASA Astrophysics Data System (ADS)

Kaplan, G. H.; Bangert, J. A.; Barron, E. G.; Bartlett, J. L.; Puatua, W.; Harris, W.; Barrett, P.

2012-08-01

The Naval Observatory Vector Astrometry Software (NOVAS) is a source - code library that provides common astrometric quantities and transformations to high precision. The library can supply, in one or two subroutine or function calls, the instantaneous celestial position of any star or planet in a variety of coordinate systems. NOVAS also provides access to all of the building blocks that go into such computations. NOVAS is used for a wide variety of applications, including the U.S. portions of The Astronomical Almanac and a number of telescope control systems. NOVAS uses IAU recommended models for Earth orientation, including the IAU 2006 precession theory, the IAU 2000A and 2000B nutation series, and diurnal rotation based on the celestial and terrestrial intermediate origins. Equinox - based quantities, such as sidereal time, are also supported. NOVAS Earth orientation calculations match those from SOFA at the sub - microarcsecond level for comparable transformations. NOVAS algorithms for aberration an d gravitational light deflection are equivalent, at the microarcsecond level, to those inherent in the current consensus VLBI delay algorithm. NOVAS can be easily connected to the JPL planetary/lunar ephemerides (e.g., DE405), and connections to IMCCE and IAA planetary ephemerides are planned. NOVAS Version 3.1 introduces a Python edition alongside the Fortran and C editions. The Python edition uses the computational code from the C edition and currently mimics the function calls of the C edition. Future versions will expand the functionality of the Python edition to exploit the object - oriented features of Python. In the Version 3.1 C edition, the ephemeris - access functions have been revised for use on 64 - bit systems and for improved performance in general. NOVAS source code, auxiliary files, and documentation are available from the USNO website (http://aa.usno.navy.mil/software/novas/novas_info.php).

First Light for USNO 1.3-meter Telescope

NASA Astrophysics Data System (ADS)

Monet, A. K. B.; Harris, F. H.; Harris, H. C.; Monet, D. G.; Stone, R. C.

2001-11-01

The US Naval Observatory Flagstaff Station has recently achieved first light with its newest telescope -- a 1.3--meter, f/4 modified Ritchey-Chretien,located on the grounds of the station. The instrument was designed to produce a well-corrected field 1.7--degrees in diameter, and is expected to provide wide-field imaging with excellent astrometric properties. A number of test images have been obtained, using a temporary CCD camera in both drift and stare mode, and the results have been quite encouraging. Several astrometric projects are planned for this instrument, which will be operated in fully automated fashion. This paper will describe the telescope and its planned large-format mosaic CCD camera, and will preview some of the research for which it will be employed.

MOTION VERIFIED RED STARS (MoVeRS): A CATALOG OF PROPER MOTION SELECTED LOW-MASS STARS FROM WISE, SDSS, AND 2MASS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Theissen, Christopher A.; West, Andrew A.; Dhital, Saurav, E-mail: ctheisse@bu.edu

2016-02-15

We present a photometric catalog of 8,735,004 proper motion selected low-mass stars (KML-spectral types) within the Sloan Digital Sky Survey (SDSS) footprint, from the combined SDSS Data Release 10 (DR10), Two Micron All-Sky Survey (2MASS) point-source catalog (PSC), and Wide-field Infrared Survey Explorer (WISE) AllWISE catalog. Stars were selected using r − i, i − z, r − z, z − J, and z − W1 colors, and SDSS, WISE, and 2MASS astrometry was combined to compute proper motions. The resulting 3,518,150 stars were augmented with proper motions for 5,216,854 earlier type stars from the combined SDSS and United States Naval Observatory B1.0 catalog (USNO-B). We used SDSS+USNO-B proper motionsmore » to determine the best criteria for selecting a clean sample of stars. Only stars whose proper motions were greater than their 2σ uncertainty were included. Our Motion Verified Red Stars catalog is available through SDSS CasJobs and VizieR.« less

Using USNO's API to Obtain Data

NASA Astrophysics Data System (ADS)

Lesniak, Michael V.; Pozniak, Daniel; Punnoose, Tarun

2015-01-01

The U.S. Naval Observatory (USNO) is in the process of modernizing its publicly available web services into APIs (Application Programming Interfaces). Services configured as APIs offer greater flexibility to the user and allow greater usage. Depending on the particular service, users who implement our APIs will receive either a PNG (Portable Network Graphics) image or data in JSON (JavaScript Object Notation) format. This raw data can then be embedded in third-party web sites or in apps.Part of the USNO's mission is to provide astronomical and timing data to government agencies and the general public. To this end, the USNO provides accurate computations of astronomical phenomena such as dates of lunar phases, rise and set times of the Moon and Sun, and lunar and solar eclipse times. Users who navigate to our web site and select one of our 18 services are prompted to complete a web form, specifying parameters such as date, time, location, and object. Many of our services work for years between 1700 and 2100, meaning that past, present, and future events can be computed. Upon form submission, our web server processes the request, computes the data, and outputs it to the user.Over recent years, the use of the web by the general public has vastly changed. In response to this, the USNO is modernizing its web-based data services. This includes making our computed data easier to embed within third-party web sites as well as more easily querying from apps running on tablets and smart phones. To facilitate this, the USNO has begun converting its services into APIs. In addition to the existing web forms for the various services, users are able to make direct URL requests that return either an image or numerical data.To date, four of our web services have been configured to run with APIs. Two are image-producing services: "Apparent Disk of a Solar System Object" and "Day and Night Across the Earth." Two API data services are "Complete Sun and Moon Data for One Day" and "Dates of Primary Phases of the Moon." Instructions for how to use our API services as well as examples of their use can be found on one of our explanatory web pages and will be discussed here.

VizieR Online Data Catalog: The URAT Parallax Catalog (UPC). Update 2018 (Finch+, 2018)

NASA Astrophysics Data System (ADS)

Finch, C. T.; Zacharias, N.; Jao, W.-C.

2018-03-01

United States Naval Observatory (USNO) Robotic Astrometric Telescope (URAT) Parallax Catalog south (UPCs) and north (UPCn). These data are based on the accepted paper for the Astronomical Journal (2018) by C. Finch, N. Zacharias, and W.-C. Jao, "URAT south parallax results: discovery of new nearby stars" (2018AJ....155..176F). The southern data are new, while the northern data contain a subset of the previously published UPC catalog after applying the more stringent selection criteria of the south data and supplementing the data with columns of the southern data. The previously published URAT Parallax Catalog (UPC) paper is: C. Finch and N. Zacharias (2016AJ....151..160F, Cat. J/AJ/151/160) (arXiv:1604.06739). (3 data files).

Fleet Weather Center- San Diego, California - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You Oceanography Portal at its new location: http://www.metoc.navy.mil/fwcsd/fwc-sd.html USNO Master Clock Time for Atlantic Tropical Warnings Naval Meteorology and Oceanography Command, 1100 Balch Blvd, Stennis

THE FOURTH US NAVAL OBSERVATORY CCD ASTROGRAPH CATALOG (UCAC4)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zacharias, N.; Finch, C. T.; Bartlett, J. L.

2013-02-01

The fourth United States Naval Observatory (USNO) CCD Astrograph Catalog, UCAC4, was released in 2012 August (double-sided DVD and CDS data center Vizier catalog I/322). It is the final release in this series and contains over 113 million objects; over 105 million of them with proper motions (PMs). UCAC4 is an updated version of UCAC3 with about the same number of stars also covering all-sky. Bugs were fixed, Schmidt plate survey data were avoided, and precise five-band photometry was added for about half the stars. Astrograph observations have been supplemented for bright stars by FK6, Hipparcos, and Tycho-2 data tomore » compile a UCAC4 star catalog complete from the brightest stars to about magnitude R = 16. Epoch 1998-2004 positions are obtained from observations with the 20 cm aperture USNO Astrograph's 'red lens', equipped with a 4k by 4k CCD. Mean positions and PMs are derived by combining these observations with over 140 ground- and space-based catalogs, including Hipparcos/Tycho and the AC2000.2, as well as unpublished measures of over 5000 plates from other astrographs. For most of the faint stars in the southern hemisphere, the first epoch plates from the Southern Proper Motion program form the basis for PMs, while the Northern Proper Motion first epoch plates serve the same purpose for the rest of the sky. These data are supplemented by 2MASS near-IR photometry for about 110 million stars and five-band (B, V, g, r, i) APASS data for over 51 million stars. Thus the published UCAC4, as were UCAC3 and UCAC2, is a compiled catalog with the UCAC observational program being a major component. The positional accuracy of stars in UCAC4 at mean epoch is about 15-100 mas per coordinate, depending on magnitude, while the formal errors in PMs range from about 1 to 10 mas yr{sup -1} depending on magnitude and observing history. Systematic errors in PMs are estimated to be about 1-4 mas yr{sup -1}.« less

Data mining in the young open cluster IC2391

NASA Astrophysics Data System (ADS)

Dodd, R. J.

2004-12-01

Large-scale astrometric and photometric data bases have been used to search for and confirm stellar membership of the open cluster IC2391. 125 stars were found that satisfied criteria for membership based on proper motion components and BRI photometry from the United States Naval Observatory B (USNO-B) catalogue and JHK photometry from the Two Micron All Sky Survey (2MASS) catalogue. This listing was compared with others recently published. A distance to the cluster of 147.7 +/- 5.5 pc was found with mean proper motion components, from the Tycho2 catalogue of (-25.04 +/- 1.53 masyr-1+23.19+/-1.23 masyr-1). A revised Trumpler classification of II3r is suggested. Luminosity and mass functions for the candidate stars were constructed and compared with those of field stars and other clusters.

Astronomical ephemerides, navigation and war. The astonishing cooperation of the ephemeris institutes of Germany, England, France and the USA during the Second World War based on documents in the archives of the Astronomisches Rechen-Institut. Edition of the documents. (German Title: Astronomische Ephemeriden, Navigation und Krieg. Die erstaunliche Zusammenarbeit der Ephemeriden-Institute von Deutschland, England, Frankreich und den USA im Zweiten Weltkrieg nach Dokumenten im Archiv des Astronomischen Rechen-Instituts. Edition der Dokumente.)

NASA Astrophysics Data System (ADS)

Wielen, Roland; Wielen, Ute

During the whole period of the Second World War, England and the USA have exchanged astronomical ephemerides with Germany, even though these data were used for the navigation of warships and aircraft and were therefore of war importance. This astonishing fact is attested by numerous documents which survived in the archives of the Astronomisches Rechen-Institut (ARI). In Germany, the exchange was even explicitly authorized by the ministry which supervised the ARI (i.e. the Reichserziehungsminister). We present here examples of ephemerides for the Sun, the Moon, planets and stars, and explain the position determination by means of astronomical data. Ephemerides were published in almanacs which were computed and issued by special ephemeris institutes. We describe the agreements on the international exchange of ephemerides which were reached in peace times, and the continuation of this exchange during the war using intermediaries in neutral countries, first in the USA (U.S. Naval Observatory, USNO), and, from 1942 onwards, in Sweden (Stockholm Observatory). Involved persons were especially H. Spencer Jones (Astronomer Royal, Greenwich), J. F. Hellweg und W. J. Eckert (USNO), B. Lindblad (Sweden), and A. Kopff (ARI). All those relevant documents which are hold in the archives of the ARI, are described and annotated in detail. Scans of these documents are presented in a separate supplement.

Historical Photos, Artwork, and Objects - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You along with a vast collection of rare astronomy texts. USNO Master Clock Time Javascript must be Enabled

Assessment of GPS carrier-phase stability for time-transfer applications.

PubMed

Larson, K M; Levine, J; Nelson, L M; Parker, T E

2000-01-01

We have conducted global positioning system (GPS) carrier-phase time-transfer experiments between the master clock (MC) at the U.S. Naval Observatory (USNO) in Washington, DC and the alternate master clock (AMC) at Schriever Air Force Base near Colorado Springs, Colorado. These clocks are also monitored on an hourly basis with two-way satellite time-transfer (TWSTT) measurements. We compared the performance of the GPS carrier phase and TWSTT systems over a 236-d period. Because of power problems and data outages during the carrier-phase experiment, the longest continuous time span is 96 d. The data from this period show agreement with TWSTT within +/-1 ns, apart from an overall constant time offset (caused by unknown delays in the GPS hardware at both ends). For averaging times of a day, the carrier-phase and TWSTT systems have a frequency uncertainty of 2.5 and 5.5 parts in 10(15), respectively.

Obituary: R(oyal) Glenn Hall, 1921-2004

NASA Astrophysics Data System (ADS)

McCarthy, Dennis Dean

2004-12-01

R. Glenn Hall died on 25 June 2004 following a battle with prostate cancer. His contributions to the determination of the frequency corresponding to an energy level transition in the Cesium atom led to the definition of the length of the second and formed the basis for precise modern timekeeping. Glenn was born on 23 June 1921 in Koloa, Hawaii, and together with a brother and three sisters, grew up in Albion, Michigan. His father was a professor of political science at Albion College. He graduated from Park College in Parkville, Missouri with a degree in mathematics in 1941. He served as a corpsman in the U. S. Navy during World War II, and went on to earn a PhD at the University of Chicago in 1949. Glenn joined the faculty at the University of Chicago as an instructor from 1949 through 1952 and became a research associate there in 1953. While at the U. of Chicago he worked extensively on mass ratios of binary stars, binary star orbits and the determination of stellar parallaxes. In 1953 Glenn came to the U. S. Naval Observatory (USNO) where he became the Assistant Director of the Time Service Division. His early work at the Naval Observatory was related to the determination of Ephemeris Time (ET) from photographic observations of the Moon with respect to background stars. This work provided a time scale more uniform than that based on the Earth's rotation, which was the internationally accepted time scale at the time. As a result, the International Astronomical Union in 1955 redefined the second to be the second as determined from Ephemeris Time. In June 1955, L. Essen and J.V.L. Parry placed in operation a Cesium beam atomic standard at the National Physical Laboratory in Teddington, England. William Markowitz (1907-1998), the director of the Time Service, and Hall together with Essen and Parry then began the work leading to the determination of the frequency of the Cesium atom in terms of the second of the seasonally corrected time scale determined from the Earth's rotation and also in terms of Ephemeris Time. The former was accomplished using the observations of stars with the Photographic Zenith Tube (PZT) and the latter from the photographic observations of the Moon. These same investigators later calibrated the frequency in terms of the ET second using observations made with the USNO dual-rate Moon camera over the period 1955.50 to 1958.25. In a paper published in Physical Review Letters in 1958 the cesium frequency was found to be 9 192 631 770 Hz with a probable error of ±20 Hz. In 1967 the 13th General Conference on Weights and Measures adopted the atomic second as the unit of time in the International System of Units. It was defined as "the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom." Therefore, the second of atomic time, the basis for all modern timekeeping, is in principle equivalent to the second of Ephemeris Time. Glenn went on to lead an international program of Moon-camera observations for the International Geophysical Year in 1957-58 that was extended into the 1960's. His other work at the U. S. Naval Observatory was concerned with the operation of programs using the Danjon astrolabes and PZTs to determine the variations in the Earth's rotation. He also worked with Markowitz to investigate improvements in electronic time transfer techniques using artificial satellites and Loran-C. Other investigations were concerned with the calibration of Hydrogen masers and the formation of time scales. Hall was a member of the American Astronomical Society and the International Astronomical Union. He retired from the USNO in 1982, and enjoyed an active retirement. He traveled widely, often returning to Hawaii, and pursued his many hobbies: he was an avid bridge player; he had a long interest in stamp collecting and maintained a large garden. In 1943 he was married to Mary Mowry. They had three children. A daughter, Anne preceded him in death in 1997. His wife and two sons, Thomas, and Robert, and two grandchildren, Garrett and Tarek, survive him. Glenn's scientific work was characterized by a clear analytical sense in the treatment of data. He possessed an ability to recognize systematic phenomena in time series data that were not always evident to his colleagues. This quality together with his friendly, unflappable nature made him a key individual at the Naval Observatory where he could always be approached for his friendly technical advice.

``Hands-Free'' Asteroid Astrometry

NASA Astrophysics Data System (ADS)

Monet, A. K. B.; Bowell, E.; Monet, D. G.

1997-12-01

How do you undertake a major new astrometric program with no additional financial or personnel resources? The answer: automation! Early in 1992, the authors began a collaboration to obtain astrometric positions for several classes of asteroids (V_lim 17.5 mag) whose orbits required improvement or that were otherwise of special interest. The telescope used for this work is the USNOFS 0.2-meter transit telescope, equipped with a CCD camera. The operation of this instrument has been fully automated (Stone, et al. 1996, AJ, 111, 1721. Nightly observing rosters are constructed from a ranked listing of all asteroids of interest, prepared each month by Bowell. In a typical month, about 200 observations are made, although this number can range from 0 to over 400. Reductions are done automatically as well. A typical 10-hr nightly run can be fully reduced in less than 1/2 hr. Reductions are made on a frame-by-frame basis and positions of the asteroids computed with respect to the USNO-A1.0 catalog (Monet, D.G. 1996, USNO-A1.0 Catalog -- 10 CD-ROM Set, US Naval Observatory.) Observational quality is checked by Bowell, who also recomputes orbits and reports final results to the Minor Planet Center. Orbit residuals hover around 0.3 arcsec. This poster will present a brief overview of the observing and analysis methods, an account of the first five years of results, and a description of planned improvements in instrumentation and analysis techniques.

Explanatory Supplement to the Astronomical Almanac, Third Edition

NASA Astrophysics Data System (ADS)

Seidelmann, P. Kenneth; Urban, S. E.

2010-01-01

"The Explanatory Supplement to the Astronomical Almanac" (hereafter "The Explanatory Supplement") is a comprehensive reference book on the topic of positional astronomy, covering the theories and algorithms used to produce "The Astronomical Almanac" (AsA), an annual publication produced jointly by the Nautical Almanac Office of the US Naval Observatory (USNO) and Her Majesty's Nautical Almanac Office (HMNAO) of the UK Hydrographic Office. The first edition of The Explanatory Supplement appeared in 1961 and was reprinted with amendments during the 1970s. The second edition was printed in 1992 and reprinted until 2006. Since the second edition, several changes have taken place in positional astronomy regarding reference systems and internationally accepted models, data sets, and computational methods; these have been incorporated into the AsA. Additionally, the data presented in the AsA have been modified over the years, with new tables being added and some being discontinued. Given these changes, a new edition of The Explanatory Supplement is appropriate. The third edition has been in development for the last few years and will be available in 2010. The book is organized similarly to the second (1991) edition, with each chapter written by subject matter experts. Authors from USNO and HMNAO contributed to the majority of the book, but there are authors from Jet Propulsion Laboratory, Technical University of Dresden, National Geospatial-Intelligence Agency, University of Texas Austin, and University of Virginia. This paper will discuss this latest edition of the Explanatory Supplement.

Explanatory Supplement to the Astronomical Almanac (3rd Edition)

NASA Astrophysics Data System (ADS)

Urban, Sean E.; Seidelmann, P. K.

2014-01-01

Publications and software from the the Astronomical Applications Department of the US Naval Observatory (USNO) are used throughout the world, not only in the Department of Defense for safe navigation, but by many people including other navigators, astronomers, aerospace engineers, and geodesists. Products such as The Nautical Almanac, The Astronomical Almanac, and the Multiyear Interactive Computer Almanac (MICA) are regarded as international standards. To maintain credibility, it is imperative that the methodologies employed and the data used are well documented. "The Explanatory Supplement to the Astronomical Almanac" (hereafter, "The ES") is a major source of such documentation. It is a comprehensive reference book on positional astronomy, covering the theories and algorithms used to produce The Astronomical Almanac, an annual publication produced jointly by the Nautical Almanac Office of USNO and Her Majesty's Nautical Almanac Office (HMNAO). The first edition of The ES appeared in 1961, and the second followed in 1992. Several major changes have taken place in fundamental astronomy since the second edition was published. Advances in radio observations allowed the celestial reference frame to be tied to extragalactic radio sources, thus the International Celestial Reference System replaced the FK5 system. The success of ESA's Hipparcos satellite dramatically altered observational astrometry. Improvements in Earth orientation observations lead to new precession and nutation theories. Additionally, a new positional paradigm, no longer tied to the ecliptic and equinox, was accepted. Largely because of these changes, staff at USNO and HMNAO decided the time was right for the next edition of The ES. The third edition is now available; it is a complete revision of the 1992 book. Along with subjects covered in the previous two editions, the book also contains descriptions of the major advancements in positional astronomy over the last 20 years, some of which are described above. Extensive references to online information are given. This paper will discuss this latest edition of the Explanatory Supplement.

Bi-static Optical Observations of GEO Objects

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Barker, Edwin S.; Cowardin, Heather; Lederer, Susan M.; Buckalew, Brent

2014-01-01

A bi-static study of objects at Geosynchronous Earth Orbit (GEO) was conducted using two ground-based wide-field optical telescopes. The University of Michigan's 0.6-m MODEST (Michigan Orbital Debris Survey Telescope) located at the Cerro Tololo Inter- American Observatory in Chile was employed in a series of coordinated observations with the U.S. Naval Observatory's (USNO) 1.3-m telescope at the USNO Flagstaff Station near Flagstaff, Arizona, USA. The goals of this project are twofold: (1) Obtain optical distances to known and unknown objects at GEO from the difference in the observed topocentric position of objects measured with respect to a reference star frame. The distance can be derived directly from these measurements, and is independent of any orbital solution. The wide geographical separation of these two telescopes means that the parallax difference is larger than ten degrees, and (2) Compare optical photometry in similar filters of GEO objects taken during the same time period from the two sites. The object's illuminated surfaces presented different angles of reflected sunlight to the two telescopes.During a four hour period on the night.of 22 February 2014 (UT), coordinated observations were obtained for eight different GEO positions. Each coordinated observation sequence was started on the hour or half-hour, and was selected to ensure the same cataloged GEO object was available in the field of view of both telescopes during the thirty minute observing sequence. GEO objects were chosen to be both controlled and uncontrolled at a range of orbital inclinations, and the objects were not tracked. Instead both telescopes were operated with all drives off in GEO survey mode to discover un-cataloged objects at GEO. The initial results from this proof-of-concept observing run will be presented, with the intent of laying the foundation for future large-scale bi-static observing campaigns of the GEO regime.

Ideas for Future GPS Timing Improvements

NASA Technical Reports Server (NTRS)

Hutsell, Steven T.

1996-01-01

Having recently met stringent criteria for full operational capability (FOC) certification, the Global Positioning System (GPS) now has higher customer expectations than ever before. In order to maintain customer satisfaction, and the meet the even high customer demands of the future, the GPS Master Control Station (MCS) must play a critical role in the process of carefully refining the performance and integrity of the GPS constellation, particularly in the area of timing. This paper will present an operational perspective on several ideas for improving timing in GPS. These ideas include the desire for improving MCS - US Naval Observatory (USNO) data connectivity, an improved GPS-Coordinated Universal Time (UTC) prediction algorithm, a more robust Kalman Filter, and more features in the GPS reference time algorithm (the GPS composite clock), including frequency step resolution, a more explicit use of the basic time scale equation, and dynamic clock weighting. Current MCS software meets the exceptional challenge of managing an extremely complex constellation of 24 navigation satellites. The GPS community will, however, always seek to improve upon this performance and integrity.

Astrometry of Single-Chord Occultations: Application to the 1993 Triton Event

NASA Technical Reports Server (NTRS)

Olkin, Catherine B.; Elliot, J. L.; Bus, Schelte J.; McDonald, Stephen W.; Dahn, Conrad C.

1996-01-01

This paper outlines a method for reducing astrometric data to derive the closest approach time and distance to the center of an occultation shadow for a single observer. The method applies to CCD frames, strip scans or photographic plates and uses a set of field stars of unknown positions to define a common coordinate system for all frames. The motion of the occulting body is used to establish the transformation between this common coordinate system and the celestial coordinate system of the body's ephemeris. This method is demonstrated by application to the Tr6O occultation by Triton on 1993 July 10 UT. Over an interval of four nights that included the occultation time, 80 frames of Triton and Tr6O were taken near the meridian with the U.S. Naval Observatory (USNO) 61-inch astrometric reflector. Application of the method presented here to these data yields a closest approach distance of 359 +/- 133 km (corresponding to 0.017 +/- 0.006 arcsec) for the occultation chord obtained with the Kuiper Airborne Observatory (KAO). Comparison of the astrometric closest approach time with the KAO light-curve midtime shows a difference of 2.2 +/- 4.1 s. Relative photometry of Triton and Tr6O, needed for photometric calibration of the occultation light curve, is also presented.

GPS-based Products - Naval Oceanography Portal

Science.gov Websites

more about how to use these products, click here. Rapids 24-hr sets of GPS satellite orbits, satellite every 24 hours. Ultras 48-hour sets (24 hours past, 24 hours predicted) of GPS satellite orbits , satellite clock solutions, and earth orientation parameters. Computed by USNO's IGS Analysis Center every

External Link Disclaimer - Naval Oceanography Portal

Science.gov Websites

, the United States Department of the Navy or [command name] of the linked web sites, or the information purpose of this DoD web site. USNO Master Clock Time Javascript must be Enabled The Sky This Week The Sky | navy.com | Freedom of Information Act (FOIA) | External Link Disclaimer This is an official U.S. Navy web

Hamilton Jeffers and the Double Star Catalogues

NASA Astrophysics Data System (ADS)

Tenn, Joseph S.

2013-01-01

Astronomers have long tracked double stars in efforts to find those that are gravitationally-bound binaries and then to determine their orbits. Court reporter and amateur astronomer Shelburne Wesley Burnham (1838-1921) published a massive double star catalogue containing more than 13,000 systems in 1906. The next keeper of the double stars was Lick Observatory astronomer Robert Grant Aitken (1864-1951), who produced a much larger catalogue in 1932. Aitken maintained and expanded Burnham’s records of observations on handwritten file cards, eventually turning them over to Lick Observatory astrometrist Hamilton Moore Jeffers (1893-1976). Jeffers further expanded the collection and put all the observations on punched cards. With the aid of Frances M. "Rete" Greeby (1921-2002), he made two catalogues: an Index Catalogue with basic data about each star, and a complete catalogue of observations, with one observation per punched card. He enlisted Willem van den Bos of Johannesburg to add southern stars, and they published the Index Catalogue of Visual Double Stars, 1961.0. As Jeffers approached retirement he became greatly concerned about the disposition of the catalogues. He wanted to be replaced by another "double star man," but Lick Director Albert E. Whitford (1905-2002) had the new 120-inch reflector, the world’s second largest telescope, and he wanted to pursue modern astrophysics instead. Jeffers was vociferously opposed to turning over the card files to another institution, and especially against their coming under the control of Kaj Strand of the U.S. Naval Observatory. In the end the USNO got the files and has maintained the records ever since, first under Charles Worley (1935-1997), and, since 1997, under Brian Mason. Now called the Washington Double Star Catalog (WDS), it is completely online and currently contains more than 1,000,000 measures of more than 100,000 pairs.

Experimental comparison of time synchronization techniques by means of light signals and clock transport on the rotating earth

NASA Technical Reports Server (NTRS)

Nelson, R. A.; Alley, C. O.; Rayner, J. D.; Shih, Y. H.; Steggerda, C. A.; Wang, B. C.; Agnew, B. W.

1993-01-01

An experiment was conducted to investigate the equivalence of two methods of time transfer in a noninertial reference frame: by means of an electromagnetic signal using laser light pulses and by means of the slow ground transport of a hydrogen maser atomic clock. The experiment may also be interpreted as an investigation of whether the one-way speeds of light in the east-west and west-east directions on the rotating earth are the same. The light pulses were sent from a laser coupled to a telescope at the NASA Goddard Optical Research Facility (GORF) in Greenbelt, Maryland to the U.S. Naval Observatory (USNO) in Washington, DC. The optical path was made possible by a 30-cm flat mirror on a water tower near GORF and a 25-cm flat mirror on top of the Washington National Cathedral near USNO. The path length was 26.0 km with an east-west component of 20.7 km. The pulses were reflected back over the same path by a portable array of corner cube reflectors. The transmission and return times were measured with a stationary Sigma Tau hydrogen maser and a University of Maryland event timer at GORF, while the times of reflection were measured with a similar maser and event timer combination carefully transported to USNO. Both timekeeping systems were housed in highly insulated enclosures and were maintained at constant temperatures to within +/- 0.1 C by microprocessor controllers. The portable system was also protected from shock and vibration by pneumatic supports. The difference delta(T) between the directly measured time of reflection according to the portable clock and the time of reflection calculated from the light pulse signal times measured by the stationary clock was determined. For a typical trip delta(T) is less than 100 ps and the corresponding limit on an anisotropy of the one-way speed of light is delta(c/c) is less than 1.5 x 10(exp -6). This the only experiment to date in which two atomic clocks were calibrated at one location, one was slowly transported to the other end of a path, and the times of transmission, reflection, and return of short light pulses sent in different directions along the path were registered.

Improving the Determination of Eastern Elongations of Planetary Satellites in the Astronomical Almanac

NASA Astrophysics Data System (ADS)

Rura, Christopher; Stollberg, Mark

2018-01-01

The Astronomical Almanac is an annual publication of the US Naval Observatory (USNO) and contains a wide variety of astronomical data used by astronomers worldwide as a general reference or for planning observations. Included in this almanac are the times of greatest eastern and northern elongations of the natural satellites of the planets, accurate to 0.1 hour UT. The production code currently used to determine elongation times generates X and Y coordinates for each satellite (16 total) in 5 second intervals. This consequentially caused very large data files, and resulted in the program devoted to determining the elongation times to be computationally intensive. To make this program more efficient, we wrote a Python program to fit a cubic spline to data generated with a 6-minute time step. This resulted in elongation times that were found to agree with those determined from the 5 second data currently used in a large number of cases and was tested for 16 satellites between 2017 and 2019. The accuracy of this program is being tested for the years past 2019 and, if no problems are found, the code will be considered for production of this section of The Astronomical Almanac.

Obituary: Ian R. Bartky, 1934-2007

NASA Astrophysics Data System (ADS)

Dick, Steven J.

2009-01-01

Ian Robertson Bartky, a physical chemist who turned to history for his second career, died 18 December 2007 of complications from lung cancer. He was 73. In addition to his scientific career, he will be remembered for his meticulous research on the evolution of time systems, especially for his two books Selling the True Time: Nineteenth Century Timekeeping in America (Stanford University Press, 2000), and One Time Fits All: The Campaigns for Global Uniformity (Stanford University Press, 2007). Ian was born on 15 March 1934 in Chicago, Illinois. He was the son of Walter Bartky, a Professor of Astronomy at the University of Chicago, and eventually its Dean of the Division of Physical Sciences. The elder Bartky's astronomy textbook, Highlights of Astronomy, published in 1935 and reprinted as late as 1964, includes a considerable discussion of time and standard meridians, which may have influenced Ian, even though his father died in 1958 at the age of 57 when Ian would have been only in his early 20s. Imbued with the love of science from his father, Ian graduated from Illinois Institute of Technology, and went on to obtain his doctorate in physical chemistry from the University of California Berkeley. He mentor was Nobelist William F. Giauque, and Ian always spoke fondly of Giauque's influence in setting rigorous standards that Ian followed when he joined the National Bureau of Standards [NBS] in 1961. Ian spent most of his career there, and it was there that he acquired his professional interest in time, notably when the House Commerce Committee asked him in the mid-1970s to determine whether the dates of Daylight Saving Time should be extended. This resulted in an NBS report in 1976, which concluded that any energy savings would be miniscule. With his usual attention to detail, Ian researched the entire history of the problem, and thus acquired his second great love after science--history. With Elizabeth Harrison he published a well-known article on the issues involved with Daylight Saving Time in Scientific American for 1979. My first interaction with Ian was leading up to the 150th anniversary of the United States Naval Observatory [USNO] in December 1980. While working on an article for Sky and Telescope on the early history of the Naval Observatory, I ran across documents in the National Archives from England proposing that the Navy's new Depot of Charts and Instruments--forerunner of the Observatory--erect a time ball as had been done in Portsmouth England in 1829. Ian had been in the National Archives working on the history of time. When I mentioned this 1829 document, he said it was impossible, because the first time ball in the world was in 1833 at Greenwich, England. But the documents told the story, and this Eureka moment led to our article in the Journal for the History of Astronomy (volume 12, October 1981), on the world's first time ball. This was to the considerable chagrin of the staff at Greenwich, who thought they had the world's first time ball, and who still ceremonially drop one at 1 PM local time. Ian went on to write the history of time balls for the Naval Observatory's sesquicentennial symposium at the end of 1980, as published in Sky with Ocean Joined. We then collaborated on another article for JHA (volume 13, February 1982) on the history of the first North American time ball, dropped at the USNO beginning in 1845. Time balls and Daylight Saving Time were only a small part of Ian's interest in time as he began to untangle the many issues involved in the history of timekeeping and time dissemination. His book Selling the True Time is a model of scholarship, and with it Ian proved to have that rare combination--a scientist with deep technical knowledge who could also ask and answer profound historical questions. He also had a keen appreciation of the role of human nature in history, always looking for the motivations for particular historical actions. Ian was proud to have the book published by Stanford University Press. When Stanford also published his final book One Time Fits All: The Campaigns for Global Uniformity, he was very proud of the glowing endorsement from Peter Galison, one of the country's foremost historians of science. With this book Ian also became the world's expert on the International Date Line, time zones, and standard time, among other aspects of time. Ian's historical work was supported by the National Science Foundation, the Dudley Observatory, and the National Maritime Museum of the Royal Observatory at Greenwich, where his work was highly regarded. He was active in many professional organizations, including the Historical Astronomy Division of the American Astronomical Society. On 29 March 2008 almost exactly 50 years after the death of his father, a memorial service was held in the library of the U. S. Naval Observatory, which had become Ian's second home during his researches, often accompanied by his wife Betty, to whom he dedicated his last book, calling her his "steadfast partner in this endeavor." The service, entitled "The Time of His Life: A Celebration of Research in the Development of Standard Timekeeping," included remarks by numerous colleagues and friends, surrounded by the books he so loved. Ian is survived by his wife of 47 years, Elizabeth Hodgins Bartky of Bethesda, Maryland, a son David J. Bartky, and a daughter Anne B. Goldberg.

The Sky This Week, 2016 January 27 - February 2 - Naval Oceanography

Science.gov Websites

Oceanography Ice You are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Sky This Week The Sky This Week, 2016 January 27 - February 2 Info The Sky This Week, 2016 January 27 - February 2 Lest we forget. NOFS_Winter_2016_01small.jpg Dome of the Kaj Strand 1.55-meter (61-inch

Advances in time-scale algorithms

NASA Technical Reports Server (NTRS)

Stein, S. R.

1993-01-01

The term clock is usually used to refer to a device that counts a nearly periodic signal. A group of clocks, called an ensemble, is often used for time keeping in mission critical applications that cannot tolerate loss of time due to the failure of a single clock. The time generated by the ensemble of clocks is called a time scale. The question arises how to combine the times of the individual clocks to form the time scale. One might naively be tempted to suggest the expedient of averaging the times of the individual clocks, but a simple thought experiment demonstrates the inadequacy of this approach. Suppose a time scale is composed of two noiseless clocks having equal and opposite frequencies. The mean time scale has zero frequency. However if either clock fails, the time-scale frequency immediately changes to the frequency of the remaining clock. This performance is generally unacceptable and simple mean time scales are not used. First, previous time-scale developments are reviewed and then some new methods that result in enhanced performance are presented. The historical perspective is based upon several time scales: the AT1 and TA time scales of the National Institute of Standards and Technology (NIST), the A.1(MEAN) time scale of the US Naval observatory (USNO), the TAI time scale of the Bureau International des Poids et Measures (BIPM), and the KAS-1 time scale of the Naval Research laboratory (NRL). The new method was incorporated in the KAS-2 time scale recently developed by Timing Solutions Corporation. The goal is to present time-scale concepts in a nonmathematical form with as few equations as possible. Many other papers and texts discuss the details of the optimal estimation techniques that may be used to implement these concepts.

VizieR Online Data Catalog: USNO Photographic Parallaxes. I. (Monet+, 1992)

NASA Astrophysics Data System (ADS)

Monet, D. G.; Dahn, C. C.; Vrba, F. J.; Harris, H. C.; Pier, J. R.; Luginbuhl, C. B.; Ables, H. D.

2000-11-01

The U.S. Naval Observatory CCD trigonometric parallax program is described in detail, including the instrumentation employed, observing procedures followed, and reduction procedures applied. Astrometric results are presented for 72 stars ranging in apparent brightness from V=15.16 to 19.58. Photometry (V and V-I on the Kron-Cousins system) is presented for the parallax stars and for all 426 individual reference stars employed in the astrometric solutions. Corrections for differential color refraction, calibrated to the observed V-I colors, have been applied to all astrometric measures. The mean errors in the relative parallaxes range from ±0.0005" to ±0.0027" with a median value of ±0.0010". Seventeen of the 23 stars with Vtan>200km/s form a well-delineated sequence of extreme subdwarfs covering 11.5

Keepers of the double stars

NASA Astrophysics Data System (ADS)

Tenn, Joseph S.

2013-03-01

Astronomers have long tracked double stars in efforts to find those that are gravitationally-bound binaries and then to determine their orbits. Early catalogues by the Herschels, Struves, and others began with their own discoveries. In 1906 court reporter and amateur astronomer Sherburne Wesley Burnham published a massive double star catalogue containing data from many observers on more than 13,000 systems. Lick Observatory astronomer Robert Grant Aitken produced a much larger catalogue in 1932 and coordinated with Robert Innes of Johannesburg, who catalogued the southern systems. Aitken maintained and expanded Burnham's records of observations on handwritten file cards, and eventually turned them over to the Lick Observatory, where astrometrist Hamilton Jeffers further expanded the collection and put all the observations on punched cards. With the aid of Frances M. "Rete" Greeby he made two catalogues: an Index Catalogue with basic data about each star, and a complete catalogue of observations, with one observation per punched card. He enlisted Willem van den Bos of Johannesburg to add southern stars, and together they published the Index Catalogue of Visual Double Stars, 1961.0. As Jeffers approached retirement he became greatly concerned about the disposition of the catalogues. He wanted to be replaced by another "double star man," but Lick Director Albert E. Whitford had the new 120-inch reflector, the world's second largest telescope, and he wanted to pursue modern astrophysics instead. Jeffers was vociferously opposed to turning over the card files to another institution, and especially against their coming under the control of Kaj Strand of the United States Naval Observatory. In the end the USNO got the files and has maintained the records ever since, first under Charles Worley, and, since 1997, under Brian Mason. Now called the Washington Double Star Catalog (WDS), it is completely online and currently contains more than 1,200,000 measures of more than 125,000 star systems.

Four New Binary Stars in the Field of CL Aurigae. II

NASA Astrophysics Data System (ADS)

Kim, Chun-Hwey; Lee, Jae Woo; Duck, Hyun Kim; Andronov, Ivan L.

2010-12-01

We report on a discovery of four new variable stars (USNO-B1.0 1234-0103195, 1235- 0097170, 1236-0100293 and 1236-0100092) in the field of CL Aur. The stars are classified as eclipsing binary stars with orbital periods of 0.5137413(23) (EW type), 0.8698365(26) (EA) and 4.0055842(40) (EA with a significant orbital eccentricity), respectively. The fourth star (USNO-B1.0 1236-0100092) showed only one partial ascending branch of the light curves, although 22 nights were covered at the 61-cm telescope at the Sobaeksan Optical Astronomy Observatory (SOAO) in Korea. Fourteen minima timings for these stars are published separately. In an addition to the original discovery paper (Kim et al. 2010), we discuss methodological problems and present results of mathematical modeling of the light curves using other methods, i.e. trigonometric polynomial fits and the newly developed fit "NAV" ("New Algol Variable").

Two-Way Satellite Time Transfer Between USNO and PTB

DTIC Science & Technology

2005-08-01

Observatory 3450 Massachusetts Ave. NW Washington, DC 20392, USA Abstract—Two completely independent two-way time and frequency transfer ( TWSTFT ...for the realization of TAI. The X- band data are provided as a backup. To reach the full potential of TWSTFT , especially for time scale comparisons...ns for both links were achieved. A change of the TWSTFT transmission frequencies or satellite changes in general cause discontinuities in the series

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2005-01-01

Naval Observatory, Washington, D.C.), pp. 325-332. [15] D. Kirchner, 1999, “Two Way Satellite Time and Frequency Transfer ( TWSTFT ),” Review of...of Carrier- Phase-Based Two-Way Satellite Time and Frequency Transfer ( TWSTFT ),” in Proceedings of the 36th Annual Precise Time and Time Interval

Data Mining for Double Stars in Astrometric Catalogs

DTIC Science & Technology

2006-03-22

Astron. Gesell . de Ball (1904) 76 WFD1906a........... Cape General Catalog Gill (1906) 11 WFD1906b........... Kat. der Astron. Gesell . Becker (1906... Gesell . Skinner (1908) 73 WFD1909............. Greenwich Second Nine Year Catalog Christie (1909) 127 WFD1914............. Abbadia Observatory (Algiers...TychoDouble Star reduction project (Fabricius et al. 2002) and 14 by 2MASS. Six others were confirmed with the USNO speckle camera and 26 inch (0.7 m) refractor

News! from the Naval Observatory - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You More... Naval Meteorology and Oceanography Command, 1100 Balch Blvd, Stennis Space Center, MS 39529

The Newcomb & Michelson Velocity of Light Experiments

NASA Astrophysics Data System (ADS)

Carter, W. E.

2002-05-01

Simon Newcomb (1835-1909) is remembered as the leading American mathematical astronomer of the 19th century; Albert Michelson (1852-1931) as the leading optical experimentalist of his era, and the first American to win the Nobel Prize in physics (1907). Newcomb first became interested in measuring the velocity of light to better determine the scale of the solar system. Ensign Michelson began his velocity of light experiments while preparing to teach physics at the U.S. Naval Academy, in Annapolis, Maryland. Using private funding and Naval Academy facilities, in January 1879, Michelson obtained a value of 299,910 km/sec. In March of that same year Newcomb received an appropriation of five thousand dollars and Michelson was detailed to the U.S. Naval Observatory (USNO) to assist with experiments in Washington D. C. The instrument designed by Newcomb used a four-sided solid steel rotating mirror to avoid a failure of the type Michelson had experienced when a thin glass mirror failed from centrifugal force. The mirror was driven by compressed air operating on fan wheels at each end of the assembly. Rotation rates of 250 rev/sec were possible, in both directions, and the rate could be varied minutely by adjusting conflicting air jets. Ft. Meyers was selected for the primary station, and fixed mirror stations were placed at USNO (Foggy Bottom) and the Washington Monument. The U.S. Coast and Geodetic Survey (USC&GS) determined the distances from the rotating mirror to the fixed mirrors. They first established a few hundred meter long baseline on Analostan Island, in the Potomac River, using 4 meter long agate capped steel slide-rods. Triangulation was then used to extend the network to each of the reflector stations. Michelson participated in the Washington D.C. observations until September 1880, when he was granted a leave of absence by the Navy to study in Europe. Newcomb continued the experiments for two more years. In his final report, Newcomb gave two values for the velocity of light in vacuum. First, a value of 299,860 km/sec based only on observations made in 1882, which he preferred because he thought that they were less affected by systematic errors. Second, 299,810 km/sec based on a weighted combination of all the observations, which proved to be the more accurate value. Newcomb suggested changes to the design of the instrumentation to improve the visibility of the return image, and concluded his report by pointing out that \\"\\ in the Rocky Mountains or the Sierra Nevada no difficulty would be found in finding stations at which a return ray could be received from a distance of 30, 40, or even 50 kilometers, with little more dispersion and loss than at a distance of 4 kilometers through the air of less favored regions.\\"\\ More than 40 years later, from 1924 to 1927, Michelson fulfilled Newcombś vision by measuring the velocity of light over a 35 kilometer line between the Carnegie Institution of Washington's Mt. Wilson Observatory and Mount San Antonio, in the San Gabriel mountains of California. The USC&GS once again determined the distance between the rotating and fixed reflector, using a baseline measured with their newly acquired "invar" tapes, and triangulation. The rotating mirror had eight faces, and was made of steel to withstand the centrifugal force at 528 rev/sec. Michelson obtained a value of for the velocity of light in vacuum of 299,796 ñ 4 k/sec, compared to the value of 299,792.458 k/sec accepted today. History books do not record it as so, but Michelson's Mt. Wilson experiment might more rightly be considered the conclusion of the Newcomb-Michelson velocity of light experiments begun two decades earlier in Washington D.C.

A multimembership catalogue for 1876 open clusters using UCAC4 data

NASA Astrophysics Data System (ADS)

Sampedro, L.; Dias, W. S.; Alfaro, E. J.; Monteiro, H.; Molino, A.

2017-10-01

The main objective of this work is to determine the cluster members of 1876 open clusters, using positions and proper motions of the astrometric fourth United States Naval Observatory (USNO) CCD Astrograph Catalog (UCAC4). For this purpose, we apply three different methods, all based on a Bayesian approach, but with different formulations: a purely parametric method, another completely non-parametric algorithm and a third, recently developed by Sampedro & Alfaro, using both formulations at different steps of the whole process. The first and second statistical moments of the members' phase-space subspace, obtained after applying the three methods, are compared for every cluster. Although, on average, the three methods yield similar results, there are also specific differences between them, as well as for some particular clusters. The comparison with other published catalogues shows good agreement. We have also estimated, for the first time, the mean proper motion for a sample of 18 clusters. The results are organized in a single catalogue formed by two main files, one with the most relevant information for each cluster, partially including that in UCAC4, and the other showing the individual membership probabilities for each star in the cluster area. The final catalogue, with an interface design that enables an easy interaction with the user, is available in electronic format at the Stellar Systems Group (SSG-IAA) web site (http://ssg.iaa.es/en/content/sampedro-cluster-catalog).

Status of IGS Ultra-Rapid Products for Real-Time Applications

NASA Astrophysics Data System (ADS)

Ray, J.; Griffiths, J.

2008-12-01

Since November 2000 the International GNSS Service (IGS) has produced Ultra-rapid (IGU) products for near real-time and real-time applications. They include GPS orbits, satellite clocks, and Earth rotation parameters for a sliding 48-hr period. The first day of each update is based on the most recent GPS observational data from the IGS hourly tracking network. At the time of release, these observed products have an initial latency of 3 hr. The second day of each update consists of predictions. So the predictions between about 3 and 9 hr into the second half are relevant for true real-time uses. Originally updated twice daily, the IGU products since April 2004 have been issued four times per day, at 3, 9, 15, and 21 UTC. Up to seven Analysis Centers (ACs) contribute to the IGU combinations: Astronomical Institute of the University of Berne (AIUB), European Space Operations Center (ESOC), Geodetic Observatory Pecny (GOP), GeoForschungsZentrum (GFZ) Potsdam, Natural Resources Canada (NRC), Scripps Insitution of Oceanography (SIO), U.S. Naval Observatory (USNO). This redundancy affords a high measure of reliability and enhanced orbit accuracy. IGU orbit precision has improved markedly since late 2007. This is due to a combination of factors: decommissioning of the old, poorly behaved PRN29 in October 2007; upgraded procedures implemented by GOP around the same time, by SIO in spring 2008, and by USNO in June 2008; better handling of maneuvered satellites at the combination level starting June 2008; and stricter AC rejection criteria since July 2008. As a consequence, the weighted 1D RMS residual of the IGU orbit predictions over their first 6 hr is currently about 20 to 30 mm (after a Helmert transformation) compared to the IGS Rapid orbits, averaged over the constellation. The median residual is about 15 to 20 mm. When extended to the full 24 hr prediction period, the IGU orbit errors approximately double. Systematic rotational offsets are probably more important than random errors due to limitations in EOP predictions, especially UT1, reaching up to about 35 mm RMS (equatorial at GPS altitude) about the Z axis. The observed orbits in the first half of each IGU update have WRMS residuals of about 10 to 12 mm. Note that while the precision of the Rapid orbits is around 7 to 9 mm (compared to the IGS Finals) discontinuities between successive daily orbits imply an inaccuracy in the IGS orbits of at least 21 mm WRMS. So it is likely that the observed IGU orbits are nearly comparable in accuracy to the Rapids and that the current IGU orbit predictions are not worse by more than a factor of two or so. Only four ACs (ESOC, GFZ, NRC, USNO) contribute estimates of the satellite clocks, which limits the robustness and quality of the IGU clock products. Because the stochastic component of clock variations is not predictable, errors for the second-half IGU clock predictions grow quickly to the same level as the broadcast navigation values. But the IGU observed clocks have typical errors just about double that of the Rapids. The scatters of precise point positions using the IGU observed products are only slightly greater than for the Rapids.

VICE PRESIDENT PENCE VIEWS SOLAR ECLIPSE WITH STUDENTS AT U.S. NAVAL OBSERVATORY

NASA Image and Video Library

2017-08-21

On Monday, Aug. 21, Vice President Mike Pence welcomed students from a Washington area school to the U.S. Naval Observatory, to view the 2017 solar eclipse and learn about heliophysics – the study of our sun. The event was also attended by former NASA astronaut Pam Melroy, NASA scientist Brad Bailey, and education specialist Evelina Felicite-Maurice.

Is there a cluster in the massive star forming region IRAS 20126+4104?

NASA Astrophysics Data System (ADS)

Montes, V. A.; Hofner, Peter; Anderson, C.; Rosero, V.

2017-03-01

A Chandra X-ray Observatory ACIS-I observation and a 6 cm continuum radio observation with the Karl G. Jansky Very Large Array (VLA) together with a multiwavelength study in infrared (2MASS and Spitzer) and optical (USNO-B1.0) shows an increasing surface density of X-ray sources toward the massive protostar. There are at least 43 YSOs within 1.2 pc distance from the massive protostar. This number is consistent with typical B-type stars clusters (Lada & Lada 2003).

Pre discovery R band limits for SN 2017aew

NASA Astrophysics Data System (ADS)

Steele, I. A.; Newsam, A. M.

2017-05-01

A 90 second R band image of the galaxy NGC6948 was obtained on 2017 May 06 at 04:13UT using the 2.0m Liverpool Telescope, La Palma. The image was obtained by the National Schools Observatory on behalf of St Anne's Catholic School, Southampton, UK. Inspection of the image shows no source visible at the co-ordinates of SN 2017aew (ATel #10381) down to a limit of R=21.2 (photometry calibrated with respect to the nearby USNO object 1501-0283085).

Astronomical Surveys, Catalogs, Databases, and Archives

NASA Astrophysics Data System (ADS)

Mickaelian, A. M.

2016-06-01

All-sky and large-area astronomical surveys and their cataloged data over the whole range of electromagnetic spectrum are reviewed, from γ-ray to radio, such as Fermi-GLAST and INTEGRAL in γ-ray, ROSAT, XMM and Chandra in X-ray, GALEX in UV, SDSS and several POSS I and II based catalogues (APM, MAPS, USNO, GSC) in optical range, 2MASS in NIR, WISE and AKARI IRC in MIR, IRAS and AKARI FIS in FIR, NVSS and FIRST in radio and many others, as well as most important surveys giving optical images (DSS I and II, SDSS, etc.), proper motions (Tycho, USNO, Gaia), variability (GCVS, NSVS, ASAS, Catalina, Pan-STARRS) and spectroscopic data (FBS, SBS, Case, HQS, HES, SDSS, CALIFA, GAMA). Most important astronomical databases and archives are reviewed as well, including Wide-Field Plate DataBase (WFPDB), ESO, HEASARC, IRSA and MAST archives, CDS SIMBAD, VizieR and Aladin, NED and HyperLEDA extragalactic databases, ADS and astro-ph services. They are powerful sources for many-sided efficient research using Virtual Observatory tools. Using and analysis of Big Data accumulated in astronomy lead to many new discoveries.

Sizes, Shapes, and Satellites of Asteroids from Occultations

NASA Astrophysics Data System (ADS)

Waring Dunham, David; Herald, David Russell; Preston, Steve; Timerson, Bradley; Maley, Paul; Frappa, Eric; Hayamizu, Tsutomu; Talbot, John; Poro, Atila

2015-08-01

For 40 years, the sizes and shapes of dozens of asteroids have been determined from observations of asteroidal occultations. Some of the first evidence for satellites of asteroids was obtained from the early efforts; now, the orbits and sizes of some satellites discovered by other means have been refined from occultation observations. Also, several close binary stars have been discovered, and the angular diameters of some stars have been measured from analysis of these observations. The International Occultation Timing Association (IOTA) coordinates this activity worldwide, from predicting and publicizing the events, to accurately timing the occultations from as many stations as possible, and publishing and archiving the observations.The release of the Hipparcos and Tycho catalogs in 1997, from ESA’s Hipparcos space mission, revolutionized asteroidal occultation work, increasing the routine accuracy of the predictions and the annual number of observations by an order of magnitude. IOTA developed an efficient procedure for predicting the occultations using a combination of new star catalogs, based on Hipparcos and new star catalogs, generated mainly at the U. S. Naval Observatory (USNO), and new observations of asteroids relative to the improved astrometric nets mainly from USNO’s Flagstaff Astrometric Scanning Transit Telescope and JPL’s Table Mountain Observatory. In addition, many IOTA observers now use inexpensive low-light-level video cameras and specially built GPS video time inserters to accurately time the events. This automation has also allowed some observers to deploy multiple remote video stations across occultation paths. Then, one observer can record several “chords” across the asteroid. The cameras are sensitive enough that easily-hidden telescopes, many of which can be packed in standard air travel suitcases, can be used for many of the predicted occultations. IOTA’s network of regional coordinators collect and reduce the observations, which are deposited annually in Asteroid Occultations V12.0. EAR-A-3-RDR-OCCULTATIONS-V12.0. NASA Planetary Data System, 2014, where they are available to researchers worldwide.

Evaluation of the accuracy of LF and TV synchronization techniques inChina via portable clock.

NASA Astrophysics Data System (ADS)

Miao, Y.-R.; Pan, X.-P.; Song, J.-A.; Bian, Y.-J.; Luo, D.-C.; Zhuang, Q.-X.

Shanxi, Beijing and Shanghai observatories cooperated with the U. S. Naval Observatory in making two portable clock experiments in 1981 and 1982. A high performance cesium clock was compared with the 1 pps signals from master clock, Loran-C receiver and TV Line-6 receiver in different observatories. The comparison of the experimental results with the prediction of the time delay between transmitter and each observatory indicates that the accuracy of LF synchronization technique in China can reach ±1 μs, timing precision is 0.05 - 0.2 μs at a distance of 2000 km. (It has been shown that there is a systematic error in the Daily Relative Phase Values, Ser. 4 of the U. S. Naval Observatory for the Northwest Pacific Loran-C chain.) For passive CCTV synchronization, timing accuracy is 2 μs or better and daily frequency calibration precision is (2 - 20)×10-13.

SPECKLE INTERFEROMETRY AT THE U.S. NAVAL OBSERVATORY. XV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, Brian D.; Hartkopf, William I.; Wycoff, Gary L., E-mail: bdm@usno.navy.mi, E-mail: wih@usno.navy.mi, E-mail: glw@usno.navy.mi

2010-08-15

Results of 2433 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 1013 mean relative positions and range in separation from 0.''96 to 58.''05, with a mean separation of 13.''50. This paper is the 15th in the series of papers and covers the period 2008 January 3 through 2008 December 21.

Statistical analysis of time transfer data from Timation 2. [US Naval Observatory and Australia

NASA Technical Reports Server (NTRS)

Luck, J. M.; Morgan, P.

1974-01-01

Between July 1973 and January 1974, three time transfer experiments using the Timation 2 satellite were conducted to measure time differences between the U.S. Naval Observatory and Australia. Statistical tests showed that the results are unaffected by the satellite's position with respect to the sunrise/sunset line or by its closest approach azimuth at the Australian station. Further tests revealed that forward predictions of time scale differences, based on the measurements, can be made with high confidence.

47 CFR 25.203 - Choice of sites and frequencies.

Code of Federal Regulations, 2014 CFR

2014-10-01

... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site at Green Bank, Pocahontas County, W. Va., and at the Naval Radio..., simultaneously notify the Director, National Radio Astronomy Observatory, P.O. Box No. 2, Green Bank, W. Va...

47 CFR 97.203 - Beacon station.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944. (1) The notification must include the... Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval...

Optical Turbulence and Rawinsonde Measurements for 17-28 September 1989 at Anderson Mesa/United States Naval Observatory, Flagstaff, Arizona

DTIC Science & Technology

1990-06-27

those of the authors and do not reflect the official policy or position of the Dept of Defense or the US Government 17 COSATJ CODES 18 SUBJECT TERMS...data acquisition and use of their 31" telescope dome facility on Anderson Mesa. Also, a thank you to the Flagstaff Naval Observatory Director, Dr...telescope dome used for optical data gathering (rawinsonde launches were made Just outside the dome) is 2.2 km above sea level and located on the

Speckle Interferometry at the U.S. Naval Observatory. XXII.

NASA Astrophysics Data System (ADS)

Mason, Brian D.; Hartkopf, William I.

2017-11-01

The results of 4747 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 2667 mean relative positions and range in separation from 0.″328 to 95.″9, with a median separation of 8.″673. Eight orbits are improved. This is the 22nd in this series of papers and covers the period 2016 January 4 through 2016 December 29.

Recent developments in the construction and operation of all-metal airplanes

NASA Technical Reports Server (NTRS)

Dornier, C

1926-01-01

Experiments on the effect of atmosphere and of sea water on the building materials employed by us have been carried on for years in the North Sea with the aid of the Hamburg Naval Observatory. Parallel experiments are being made at the Pisa Naval Observatory in the Mediterranean Sea. Metal sheets, sections, assemblies and experimental floats are being exposed to the action of the elements. Different construction techniques are discussed and a variety of specific airplanes are presented which incorporate some of the new thinking.

Appendix A: The Impact of the HP 5071A on International Atomic Time

NASA Technical Reports Server (NTRS)

Allan, David W.; Lepek, Alex; Cutler, Len; Giffard, Robin; Kusters, Jack

1996-01-01

The international clock ensemble, which contributes to the generation of International Atomic Time (TAI and UTC) has improved dramatically over the last few years. The main change has been the introduction of a significant number of HP 5071A clocks. Of the 313 clocks contributing to TAI/UTC during 1994, 94 of these were HP 5071As. The environmental insensitivity of the HP 5071A clocks is more than an order of magnitude better than that of previously contributing clocks. This environmental insensitivity translates to outstanding long-term stability - with a typical flicker floor of a few x10(sup -15). in addition, there are now several hydrogen masers with cavity tuning contributing to TAI/UTC. These not only have outstanding short-term stability, but comparatively low frequency drifts and excellent intermediate-type frequency stability. By analyzing data available from the international ensemble, we have obtained two important results. First the frequency stability obtainable with an optimum algorithm is about 10(sup -15) for both the intermediate and long-term regions. It could be as good in the short-term (if time transfer measurement instabilities were reduced sufficiently. Second, with cooperation, this performance can be made available on an international basis in near real time. The recent enhancements in the contributing clocks are already providing a significant improvement in the accuracy with which UTC is made available to the world from several of the national timing centers, such as the National Institute for Standards and Technology (NIST) and the US Naval Observatory (USNO).

Morphology and Density Structure of Post-CME

DTIC Science & Technology

2010-06-26

Zagreb , Croatia 2 INAF-Arcetri Observatory, Firenze, Italy 3 Faculty of Science, Geophysical Department, Croatia 4 Naval Research Laboratory, Washington...AND ADDRESS(ES) Hvar Observatory,,Faculty of Geodes, Zagreb , Croatia, , 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME

Northern Hemisphere observations of ICRF sources on the USNO stellar catalogue frame

NASA Astrophysics Data System (ADS)

Fienga, A.; Andrei, A. H.

2004-06-01

The most recent USNO stellar catalogue, the USNO B1.0 (Monet et al. \\cite{Monet03}), provides positions for 1 042 618 261 objects, with a published astrometric accuracy of 200 mas and five-band magnitudes with a 0.3 mag accuracy. Its completeness is believed to be up to magnitude 21th in V-band. Such a catalogue would be a very good tool for astrometric reduction. This work investigates the accuracy of the USNO B1.0 link to ICRF and give an estimation of its internal and external accuracies by comparison with different catalogues, and by computation of ICRF sources using USNO B1.0 star positions.

SPECKLE INTERFEROMETRY AT THE U.S. NAVAL OBSERVATORY. XVII

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, Brian D.; Hartkopf, William I.; Wycoff, Gary L., E-mail: bdm@usno.navy.mil, E-mail: wih@usno.navy.mil

2011-08-15

The results of 3362 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 1970 mean relative positions and range in separation from 0.''78 to 72.''17, with a mean separation of 14.''76. This is the 17th in this series of papers and covers the period 2010 January 6 through December 20. Also presented are 10 pairs that are resolved for the first time.

Speckle Interferometry at the U.S. Naval Observatory. XXI.

NASA Astrophysics Data System (ADS)

Mason, Brian D.; Hartkopf, William I.; Bredthauer, Greg; Ferguson, Eric W.; Finch, Charlie T.; Kilian, Christopher M.; Rafferty, Theodore J.; Ragan, Tai J.; Wieder, Gary D.

2017-01-01

The results of 2408 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 1602 mean relative positions and range in separation from 1.″94 to 107.″41, with a median separation of 11.″96. This is the twenty-first in this series of papers and covers the period from 2015 January 13 through 2015 December 19. Significant instrumentation changes are reported in this paper.

47 CFR 25.203 - Choice of sites and frequencies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...

47 CFR 25.203 - Choice of sites and frequencies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...

47 CFR 25.203 - Choice of sites and frequencies.

Code of Federal Regulations, 2013 CFR

2013-10-01

... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...

47 CFR 25.203 - Choice of sites and frequencies.

Code of Federal Regulations, 2012 CFR

2012-10-01

... National Radio Astronomy Observatory: In order to minimize possible harmful interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, W. Va., and at the Naval... such application with the Commission, simultaneously notify the Director, National Radio Astronomy...

1RXS J184542.4+483134 is a new eclipsing polar

NASA Astrophysics Data System (ADS)

Pavlenko, E.; Sokolovsky, K.; Baklanov, A.; Antonyuk, K.; Antonyuk, O.; Denisenko, D.

2011-06-01

We present time-resolved ground-based optical and space-based Swift UV and X-ray observations of the cataclysmic variable 1RXS J184542.4+483134 (USNO-B1.0 1385-0291789 18:45:42.622 +48:31:30.84, J2000; Monet et al. 2003 AJ, 125, 984) recently identified by Denisenko & Sokolovsky (2011 AstL, 37, 91) and Denisenko & Smirnov (2011 PZP, 11, 10). Photometry with the 2.6-m Shajn and 1.25-m AZT-11 telescopes of the Crimean astrophysical observatory was conducted on 2011 April 30, May 02, 03 and April 25, 26, respectively, for the total duration of about 14.6 hrs.

Obituary: Richard L. (Dick) Walker, Jr., 1938-2005

NASA Astrophysics Data System (ADS)

Pier, Jeffrey R.; Mason, Brian

2005-12-01

Dick Walker, 67, died 30 March 2005 in Flagstaff, AZ, following a long illness. He was born on 9 March 1938 in Hampton, Iowa and grew up in Waterloo, Iowa. As a child, Dick was fascinated with astronomy and built his own telescope. He saved his pennies and bought and read every book on the subject he could find. He also raised pigeons, naming four of them Hertzsprung, Hoyle, Gamow, and Kron. In 1957, the year Sputnik was launched, Dick began his college studies at the University of Northern Iowa in Cedar Falls. In 1959, he transferred to the State University of Iowa (subsequently renamed the University of Iowa) in Iowa City, where he earned a BA degree in astronomy and physics in 1963. He joined the staff of the U.S. Naval Observatory in Washington, DC, where he worked in the Time Service Division for a year before his assignment to the Astrometry and Astrophysics Division. Dick relocated to Flagstaff, AZ, in 1966 to continue his Naval Observatory service at the Flagstaff Station. His retirement in May 1999, ended a thirty-six-year career with USNO. Dick was first and foremost an observational astronomer. From the mid 1960s through the late 1970s, much of Dick's time was devoted to the measurement of binary stars, observing with the 12-inch and 26-inch refractors in Washington and later the 40-inch and 61-inch reflectors in Flagstaff. He also made many trips to Lick Observatory to work with the 36-inch Clark Refractor there. During this time he consulted with Charles Worley, who was observing on the 26-inch, to make sure time was well-spent examining doubles that could not be observed in Washington. This period of observing overlapped with the early years of speckle interferometry, and Dick's observations, made with the largest telescope used for micrometry at the time, were very important for ascertaining the veracity of this new technique. He was a studious and very careful observer of doubles and made over 8,000 measures, resulting in almost 3,000 mean positions. While measuring known systems for orbital analysis, he discovered 22 pairs (mostly additional components to these systems) and moving pairs, and his highlighting the rapid motion of these systems resulted in them being placed on many programs and led to the more definitive orbits of today. As a staff member of the Flagstaff Station, Dick was, for over 30 years, one of the principal observers on the 61-inch parallax program. He also ventured into other areas of astronomy, including planetary systems. He is credited with discovering the moon of Saturn, Epimetheus, in December 1966, with the USNO Flagstaff Station 61-inch Kaj Strand Astrometric Reflector. He also obtained photographic plates to determine accurate positions of the outer planets for the Voyager 2 approaches to Uranus in 1986 and Neptune in 1989. It is interesting to note that Dick's career in observational astronomy spanned three different eras of astronomical instrumentation and technique. He began his career doing eyeball astronomy, using a filar micrometer to measure double star separations. Photographic astronomy then became dominant and he took many thousands of plates. During the last ten years of his career, electronic cameras, primarily CCDs, replaced photographic plates. He readily adapted to the changing technologies. A man of many interests, Dick was fascinated by the history of astronomy, especially archeoastronomy, as well as Egyptology. He taught himself the language of hieroglyphics. In 1977, having accumulated several weeks of vacation time, he set off on a trek to walk the Nile for 500 miles from Aswan to Cairo. One night, in the town Asyut along the Nile, he was brought into the police station. The local inhabitants found it hard to credit his story that he was simply on a walk and questioned him as a possible Israeli spy. Following his retirement from the Naval Observatory, Dick consulted in a couple of construction projects. He designed the analemma and the skywalk star fields for the Koch Center for Science, Math, and Technology at Deerfield Academy in Massachusetts. He also consulted with James Turrell, providing astronomical position information for the design of the Roden Crater Project outside of Flagstaff. While he will be remembered for his significant scientific contributions to the field of astronomy, those who knew Dick, both scientists and non-scientists alike, will probably remember him best for his humility, his humanity, and his loyal and abiding friendship. He was a man with a terrific sense of humor and an infectious laugh. It was always an honor and pleasure to be in his company. Richard L. Walker, Jr. is survived by his wife, Patricia, two daughters from his first marriage: Brenda Walker of Las Vegas, NV, and Pamela Hepburn of Holland, OH, as well as four children from Patricia's first marriage: Doug Browning of Lake Havasu City, AZ, Michael Browning of Kingman, AZ, Kim Bructo of Orient, OH, and Jennifer Brown of Lake Havasu City, AZ. He is also survived by ten grandchildren and three great-grandchildren. He was preceded in death by his father Richard, mother Mary, and daughter, Paula Jean Elizabeth Stone.

Results from a portable Adaptive Optics system on the 1 meter telescope at the Naval Observatory Flagstaff Station

NASA Astrophysics Data System (ADS)

Restaino, Sergio R.; Gilbreath, G. Charmaine; Payne, Don M.; Baker, Jeffrey T.; Martinez, Ty; DiVittorio, Michael; Mozurkewich, David; Friedman, Jeffrey

2003-02-01

In this paper we present results using a compact, portable adaptive optics system. The system was developed as a joint venture between the Naval Research Laboratory, Air Force Research Laboratory, and two small, New Mexico based-businesses. The system has a footprint of 18x24x18 inches and weighs less than 100 lbs. Key hardware design characteristics enable portability, easy mounting, and stable alignment. The system also enables quick calibration procedures, stable performance, and automatic adaptability to various pupil configurations. The system was tested during an engineering run in late July 2002 at the Naval Observatory Flagstaff Station one-meter telescope. Weather prevented extensive testing and the seeing during the run was marginal but a sufficient opportunity was provided for proof-of-concept, initial characterization of closed loop performance, and to start addressing some of the most pressing engineering and scientific issues.

An international campaign of the 19th century to determine the solar parallax. The US Naval expedition to the southern hemisphere 1849-1852

NASA Astrophysics Data System (ADS)

Schrimpf, Andreas

2014-04-01

In 1847 Christian Ludwig Gerling, Marburg (Germany), suggested the solar parallax to be determined by measuring the position of Venus close to its inferior conjunction, especially at the stationary points, from observatories on nearly the same meridian but widely differing in latitude. James M. Gilliss, astronomer at the newly founded U.S. Naval Observatory, enthusiastically adopted this idea and procured a grant for the young astronomical community of the United States for an expedition to Chile. There they were to observe several conjunctions of Venus and oppositions of Mars, while the accompanying measurements were to be taken at the US Naval Observatory in Washington D.C. and the Harvard College Observatory at Cambridge, USA. This expedition was supported by A.V. Humboldt, C.F. Gauß, J.F. Encke, S.C. Walker, A.D. Bache, B. Peirce and others. From 1849 to 1852 not only were astronomical, but also meteorological and magnetic observations and measurements recorded, mainly in Santa Lucia close to Santiago, Chile. By comparing these measurements with those taken simultaneously at other observatories around the world the solar parallax could be calculated, although incomplete data from the corresponding northern observatories threatened the project's success. In retrospect this expedition can be recognized as the foundation of the Chilean astronomy. The first director of the new National Astronomical Observatory of Chile was Dr. C.W. Moesta, a Hessian student of Christian Ludwig Gerling's. The exchange of data between German, American and other astronomers during this expedition was well mediated by J.G. Flügel, consul of the United States of America and representative of the Smithsonian Institution in Europe, who altogether played a major role in nurturing the relationship between the growing scientific community in the U.S. and the well established one in Europe at that time.

New reductions of the Astrographic Catalogue. Plate adjustments of the Algiers, Oxford I and II, and Vatican Zones.

NASA Astrophysics Data System (ADS)

Urban, S. E.; Martin, J. C.; Jackson, E. S.; Corbin, T. E.

1996-07-01

The U. S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue using a modern reference catalog, the ACRS, and new data analysis and reduction software. Currently ten AC zones have been reduced. This papers discusses the reduction models and results from the Algiers, Oxford I and II, and Vatican zones (those of the Cape zone are discussed elsewhere). The resulting star positions will be combined with those of the U.S. Naval Observatory's Twin Astrograph Catalog to produce a catalog of positions and proper motions in support of the Sloan Digital Sky Survey.

75 FR 33620 - Notice of Public Information Collections Being Reviewed by the Federal Communications Commission...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-14

..., Notifications Concerning Interference to Radio Astronomy, Research and Receiving Installations. Form Number: N/A... Astronomy Observatory site located at Green, Pocahontas County, West Virginia, and at the Naval Radio... the west, shall notify the Interference Office, National Radio Astronomy Observatory, P.O. Box 2...

78 FR 17664 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-22

..., Notifications Concerning Interference to Radio Astronomy, Research and Receiving Installations. Form Number: N/A... Astronomy Observatory site located at Green, Pocahontas County, West Virginia, and at the Naval Radio... Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, West Virginia 24944...

Effects of the 2011 Tohoku Earthquake on VLBI Geode- tic Measurements

NASA Astrophysics Data System (ADS)

MacMillan, D.; Behrend, D.; Kurihara, S.

2012-12-01

The VLBI antenna TSUKUB32 at Tsukuba, Japan observes in 24-hour observing sessions once per week with the R1 operational network and on additional days with other networks on a more irregular basis. Further, the antenna is an endpoint of the single-baseline, 1-hr Intensive Int2 sessions observed on the weekends for the determination of UT1. TSUKUB32 returned to normal operational observing one month after the earthquake. The antenna is 160 km west and 240 km south of the epicenter of the Tohoku earthquake. We looked at the transient behavior of the TSUKUB32 position time series following the earthquake and found that significant deformation is continuing. The eastward rate relative to the long-term rate prior to the earthquake was about 20 cm/yr four months after the earthquake and 9 cm/yr after one year. The VLBI series agrees closely with the corresponding JPL (Jet Propulsion Laboratory) GPS series measured by the co-located GPS antenna TSUK. The co-seismic UEN displacement at Tsukuba as determined by VLBI was (-90 mm, 640 mm, 44 mm). We examined the effect of the variation of the TSUKUB32 position on EOP estimates and then used the GPS data to correct its position for the estimation of UT1 in the Tsukuba-Wettzell Int2 Intensive experiments. For this purpose and to provide operational UT1, the IVS scheduled a series of weekend Intensive sessions observing on the Kokee-Wettzell baseline immediately before each of the two Tsukuba-Wettzell Intensive sessions. Comparisons between the UT1 estimates from these weekend sessions and the USNO (United States Naval Observatory) combination series were used to validate the GPS correction to the TSUKUB32 position.

George William Hill, the Great but Unknown 19th Century Celestial Mechanician

NASA Astrophysics Data System (ADS)

Corbin, Brenda G.

2012-01-01

George William Hill (1838-1914) has long been considered one of the most famous and talented celestial mechanicians of the past century and a half. However, many people have never heard of him and his work. Simon Newcomb said he "will easily rank as the greatest master of mathematical astronomy during the last quarter of the nineteenth century.” After receiving a B.A. at Rutgers in 1859, Hill began work in 1861 at the office of the American Ephemeris and Nautical Almanac in Cambridge, MA. He moved to Washington with the group in 1882 which then became part of the U. S. Naval Observatory. Newcomb, beginning his work on planetary motion, assigned the theory of Jupiter and Saturn to him, calling it about the most difficult topic. Hill's work was published by the USNO in 1890 as A New Theory of Jupiter and Saturn. From 1898 to 1901, Hill lectured on the subject of celestial mechanics at Columbia University in a position created just for him. After 1892 and until his death, he lived at the family homestead in West Nyack, NY. He never married, was something of a recluse, and spent most of his time with his books and research. Hill was an amateur botanist and enjoyed exploring on long walks in the countryside. Many honors and awards came to him during his lifetime, both from the U.S. and abroad, including serving as president of the American Mathematical Society. All of Hill's mathematical and astronomical research was incorporated in The Collected Mathematical Works of George William Hill. This work, containing a preface in French by Poincare, was published in 4 large volumes by the Carnegie Institution of Washington in 1905.

149 Sources and 15 Years Later: The Navy-NRAO Green Bank Interferometer Monitoring Program

NASA Astrophysics Data System (ADS)

Lazio, T. J. W.; Waltman, E. B.; Ghigo, F.; Johnston, K. J.

2000-12-01

Flux densities for 149 sources were monitored with the Green Bank Interferometer for durations ranging from 3 to 15 yrs, covering the interval 1979--1996, with most sources observed for 6 yrs. Observations were at two radio frequencies (approximately 2.5 and 8.2 GHz) and have a typical sampling of one flux density measurement every 2 days. We have used these light curves to conduct various variability analysis of the sources. We find suggestive, though not unambiguous evidence, that these sources have a common, broadband mechanism for intrinsic variations. We also find that the extrinsic variation is more consistent with radio-wave scattering in an extended medium rather than in a thin screen. The primary motivation for this monitoring program was the identification of extreme scattering events. In an effort to identify ESEs in a systematic manner, we have taken the wavelet transform of the light curves. We find 15 events in the light curves of 12 sources that we classify as probable ESEs. However, we also find that five ESEs previously identified from these data do not survive our wavelet selection criteria. Future identification of ESEs will probably continue to rely on both visual and systematic methods. We present examples of the light curves and variability analyses. Instructions for obtaining the data are also given. The GBI is a facility of the National Science Foundation and was operated by the National Radio Astronomy Observatory under contract to the USNO and NRL during these observations. A portion of this work was performed while TJWL held a National Research Council-NRL Research Associateship. Basic research in radio astronomy at the NRL is supported by the Office of Naval Research.

VizieR Online Data Catalog: Vilnius photometry of M29 (NGC6913) (Milasius+, 2013)

NASA Astrophysics Data System (ADS)

Milasius, K.; Boyle, R. P.; Vrba, F. J.; Janusz, R.; Straizys, V.; Cernis, K.; Laugalys, V.; Zdanavicius, K.; Zdanavicius, J.; Kazlauskas, A.; Smilgys, R.

2015-01-01

The observational material was obtained with CCD cameras on three different telescopes: the wide-field Maksutov-type 35/51cm telescope of the Moletai Observatory in Lithuania (2004), the 1m Ritchey telescope at the Flagstaff Station of the US Naval Observatory in Arizona (2006-2008) and the 1.8m VATT telescope of the Vatican Observatory on Mt. Graham, Arizona (2011-2012). (3 data files).

SPECKLE INTERFEROMETRY AT THE U.S. NAVAL OBSERVATORY. XVIII

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, Brian D.; Hartkopf, William I.; Friedman, Elizabeth A., E-mail: bdm@usno.navy.mil, E-mail: wih@usno.navy.mil, E-mail: efriedman09@ucla.edu

2012-05-15

The results of 2490 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 1462 mean relative positions and range in separation from 0.''56 to 71.''80, with a mean separation of 14.''81. This is the 18th in this series of papers and covers the period 2011 January 3 through 2011 December 18. Also presented are four pairs which are resolved for the first time, thirteen other pairs which appear to be lost, andmore » linear elements for four additional pairs.« less

Speckle Interferometry at the U.S. Naval Observatory. XIX

NASA Astrophysics Data System (ADS)

Mason, Brian D.; Hartkopf, William I.; Hurowitz, Haley M.

2013-09-01

The results of 2916 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over two thousand short-exposure images. These observations are averaged into 1584 mean relative positions and range in separation from 0.''54 to 98.''09, with a median separation of 11.''73. This is the 19th in this series of papers and covers the period 2012 January 5 through 2012 December 18. Also presented are 10 pairs that are reported for the first time, 17 pairs that appear to be lost, linear elements for 18 pairs, and orbital elements for 2 additional pairs.

Time synchronization via the transit satellite at Mizusawa

NASA Technical Reports Server (NTRS)

Hara, J.; Sato, K. H.

1978-01-01

Time signals emitted from Transit satellites and received by the NAVICODE type receiver at Mizusawa, Japan are presented. The International Latitude Observatory of Mizusawa and the U. S. Naval Observatory were compared using the time signals. Propagation delays, a receiver delay, effects of relative motion of satellites, and effects of the ionosphere are discussed.

SPECKLE INTERFEROMETRY AT THE U.S. NAVAL OBSERVATORY. XIX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, Brian D.; Hartkopf, William I.; Hurowitz, Haley M., E-mail: bdm@usno.navy.mil, E-mail: wih@usno.navy.mil, E-mail: hurowitz@mit.edu

2013-09-15

The results of 2916 intensified CCD observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over two thousand short-exposure images. These observations are averaged into 1584 mean relative positions and range in separation from 0.''54 to 98.''09, with a median separation of 11.''73. This is the 19th in this series of papers and covers the period 2012 January 5 through 2012 December 18. Also presented are 10 pairs that are reported for the first time, 17 pairs that appear to be lost, linearmore » elements for 18 pairs, and orbital elements for 2 additional pairs.« less

Plutonian Moon confirmed

NASA Astrophysics Data System (ADS)

In late February, two separate observations confirmed the 1978 discovery by U.S. Naval Observatory scientist James W. Christy of a moon orbiting the planet Pluto. According to the U.S. Naval Observatory, these two observations were needed before the International Astronomical Society (IAS) would officially recognize the discovery.Two types of observations of the moon, which was named Charon after the ferryman in Greek mythology who carried the dead to Pluto's realm, were needed for confirmation: a transit, in which the moon passes in front of Pluto, and an occultation, in which the moon passes behind the planet. These two phenomena occur only during an 8-year period every 124 years that had been calculated to take place during 1984-1985. Both events were observed in late February.

Time Transfer Between USNO and PTB: Operation and Calibration Results

DTIC Science & Technology

2004-09-01

transfer ( TWSTFT ) is routinely executed between USNO and PTB via two links, using a connection at Ku-band and X-band. The Ku-band measurements are...desirable. Up to now, three calibration experiments were carried out with a transportable TWSTFT station provided by USNO: in June 2002, January 2003...and July 2003. Because only a few TWSTFT calibrations of civil time laboratories were performed up to now, this first “semiannual” schedule

Impact of orbit, clock and EOP errors in GNSS Precise Point Positioning

NASA Astrophysics Data System (ADS)

Hackman, C.

2012-12-01

Precise point positioning (PPP; [1]) has gained ever-increasing usage in GNSS carrier-phase positioning, navigation and timing (PNT) since its inception in the late 1990s. In this technique, high-precision satellite clocks, satellite ephemerides and earth-orientation parameters (EOPs) are applied as fixed input by the user in order to estimate receiver/location-specific quantities such as antenna coordinates, troposphere delay and receiver-clock corrections. This is in contrast to "network" solutions, in which (typically) less-precise satellite clocks, satellite ephemerides and EOPs are used as input, and in which these parameters are estimated simultaneously with the receiver/location-specific parameters. The primary reason for increased PPP application is that it offers most of the benefits of a network solution with a smaller computing cost. In addition, the software required to do PPP positioning can be simpler than that required for network solutions. Finally, PPP permits high-precision positioning of single or sparsely spaced receivers that may have few or no GNSS satellites in common view. A drawback of PPP is that the accuracy of the results depend directly on the accuracy of the supplied orbits, clocks and EOPs, since these parameters are not adjusted during the processing. In this study, we will examine the impact of orbit, EOP and satellite clock estimates on PPP solutions. Our primary focus will be the impact of these errors on station coordinates; however the study may be extended to error propagation into receiver-clock corrections and/or troposphere estimates if time permits. Study motivation: the United States Naval Observatory (USNO) began testing PPP processing using its own predicted orbits, clocks and EOPs in Summer 2012 [2]. The results of such processing could be useful for real- or near-real-time applications should they meet accuracy/precision requirements. Understanding how errors in satellite clocks, satellite orbits and EOPs propagate into PPP positioning and timing results allows researchers to focus their improvement efforts in areas most in need of attention. The initial study will be conducted using the simulation capabilities of Bernese GPS Software and extended to using real data if time permits. [1] J.F. Zumberge, M.B. Heflin, D.C. Jefferson, M.M. Watkins and F.H. Webb, Precise point positioning for the efficient and robust analysis of GPS data from large networks, J. Geophys. Res., 102(B3), 5005-5017, doi:10.1029/96JB03860, 1997. [2] C. Hackman, S.M. Byram, V.J. Slabinski and J.C. Tracey, Near-real-time and other high-precision GNSS-based orbit/clock/earth-orientation/troposphere parameters available from USNO, Proc. 2012 ION Joint Navigation Conference, 15 pp., in press, 2012.

Astrometric Improvements for the USNO-A Catalog

NASA Astrophysics Data System (ADS)

Monet, D.

1997-12-01

The USNO-A1.0 catalog (Monet et al. 1996; 10 CD-ROMs; USNO) contains astrometric and photometric information for 488,006,860 objects. Since its compilation, many areas for improvement have been identified. This paper presents a progress report on the implementation of these improvements and discusses the schedule for the compilation of USNO-A2.0. The most significant improvement will be the incorporation of the International Celestial Reference Frame through the adoption of the ACT Catalog (Urban et al. in preparation; CD-ROM; USNO). (The ACT uses data from the Astrographic Catalog to compute proper motions for stars found in the Hipparcos and Tycho catalogs.) In addition to providing the realization of the astrometric reference frame, the ACT catalog contains a high enough source density to allow for a GSC-free derivation of the systematic components of the astrometric distortions found in the Schmidt telescopes that took the survey plates, and for a determination of the magnitude terms for the Palomar Schmidt using the data from the scans of the UJ plates. Other topics include the development of a numerical refocusing technique to improve the quality of existing scans, and the lessons being learned from the scanning of the Lick Northern Proper Motion survey plates.

VizieR Online Data Catalog: Cordoba Carte du Ciel-Astrographic Catalog, CCAC (Orellana+, 2010)

NASA Astrophysics Data System (ADS)

Orellana, R. B.; de Biasi, M. S.; Bustos Fierro, I. H.; Calderon, J. H.

2010-07-01

This is Cordoba Carte du Ciel-Astrographic Catalog (CCAC) constructed from four Carte du Ciel and one Astrographic Catalog photographic plates for first epoch positions in the region of the open cluster Collinder 132. The plates were digitized using the MAMA measuring machine from the Paris Observatory. Stars from Tycho-2 catalogue (Hog et al., 2000, Cat. I/259) were used as reference stars. Every plate was reduced independently from the others adopting a first order polynomial in the measured coordinates. Proper motions were calculated using the CCAC positions as first epoch, and as second epoch the positions given by UCAC2 (Zacharias et al., 2004, Cat. I/289) and USNO-B1.0 (Monet et al., 2003, Cat. I/284). (2 data files).

A Multi-Survey Approach to White Dwarf Discovery

DTIC Science & Technology

2012-04-01

LSPM-North), the Two Micron All Sky Survey ( 2MASS ), and the USNO-B1.0 catalog, we use a succession of methods to isolate white dwarf (WD) candidates...including SDSS, the Two Micron All Sky Survey ( 2MASS ; Skrutskie et al. 2006), USNO-B1.0 (Monet et al. 2003), and the proper motion survey of Lépine & Shara...Shara Proper Motion North Catalog (LSPM-North), the Two Micron All Sky Survey ( 2MASS ), and the USNO-B1.0 catalog, we use a succession of methods to

Highlights of our 4th Annual ATS Convention

NASA Astrophysics Data System (ADS)

Breyer, Walter H.

The article gives the details of the ATS's Philadelphia convention, keynote by Dr. Elizabeth Griffin of Cambridge University, visits to Swarthmore College and the Sproul Observatory, talks by Robert Ariail, Guy McCann, Eugene Rudd, John Church, Christopher Ray, Mike Reynolds, Professor Wulff Heinz, Walter Yund IV, Paul O'Leary, Ray Harris, Ed Young, Glen Oclassen, Peter Abrahams, and Ron Maddison. The awards for best exhibits went to John Mutch Jr. and John Mutch III for their extensive Zeiss collection, and Dr. Eugene Rudd for his Cater Rand's Patent Military and Naval Telescope. Visits were made also to the Flower and Cook Observatory, Haverford College Observatory, Villanova College Observatory, and the Franklin Institute.

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2012-01-01

Satellite Time Transfer (TWSTT), also referred to as Two-Way Satellite Time and Frequency Transfer ( TWSTFT ) The most accurate means of operational long...satellite broadcasts, and the BIPM uses that reported by the Observatory of Paris (OP), transferred to the BIPM via TWSTFT . This is compared to...Frequency Transfer ( TWSTFT ),” Review of Radio Science (Oxford Science Publications), pp. 27-44. [25] L. A. Breakiron, A. L. Smith, B. C. Fonville

Our Sky Now and Then: Searches for Lost Stars and Impossible Effects as Probes of Advanced Extraterrestrial Civilizations

NASA Astrophysics Data System (ADS)

Villarroel, Beatriz; Imaz, Inigo; Bergstedt, Josefine

2016-09-01

Searches for extraterrestrial intelligence using large survey data often look for possible signatures of astroengineering. We propose searching for physically impossible effects caused by highly advanced technology by carrying out a search for disappearing galaxies and Milky Way stars. We select ˜10 million objects from USNO-B1.0 with low proper motions (μ < 20 mas yr-1) imaged on the sky in two epochs. We search for objects not found at the expected positions in the Sloan Digital Sky Survey (SDSS) by visually examining images of ˜290,000 USNO-B1.0 objects with no counterpart in the SDSS. We identify some spurious targets in the USNO-B1.0. We find one candidate of interest for follow-up photometry, although it is very uncertain. If the candidate eventually is found, it defines the probability of observing a disappearing-object event in the last decade to less than one in one million in the given samples. Nevertheless, because the complete USNO-B1.0 data set is 100 times larger than any of our samples, we propose an easily accessible citizen science project in search of USNO-B1.0 objects that have disappeared from the SDSS.

Relativistic timescale analysis suggests lunar theory revision

NASA Astrophysics Data System (ADS)

Deines, Steven D.; Williams, Carol A.

1995-05-01

The SI second of the atomic clock was calibrated to match the Ephemeris Time (ET) second in a mutual four year effort between the National Physical Laboratory (NPL) and the United States Naval Observatory (USNO). The ephemeris time is 'clocked' by observing the elapsed time it takes the Moon to cross two positions (usually occultation of stars relative to a position on Earth) and dividing that time span into the predicted seconds according to the lunar equations of motion. The last revision of the equations of motion was the Improved Lunar Ephemeris (ILE), which was based on E. W. Brown's lunar theory. Brown classically derived the lunar equations from a purely Newtonian gravity with no relativistic compensations. However, ET is very theory dependent and is affected by relativity, which was not included in the ILE. To investigate the relativistic effects, a new, noninertial metric for a gravitated, translationally accelerated and rotating reference frame has three sets of contributions, namely (1) Earth's velocity, (2) the static solar gravity field and (3) the centripetal acceleration from Earth's orbit. This last term can be characterized as a pseudogravitational acceleration. This metric predicts a time dilation calculated to be -0.787481 seconds in one year. The effect of this dilation would make the ET timescale run slower than had been originally determined. Interestingly, this value is within 2 percent of the average leap second insertion rate, which is the result of the divergence between International Atomic Time (TAI) and Earth's rotational time called Universal Time (UT or UTI). Because the predictions themselves are significant, regardless of the comparison to TAI and UT, the authors will be rederiving the lunar ephemeris model in the manner of Brown with the relativistic time dilation effects from the new metric to determine a revised, relativistic ephemeris timescale that could be used to determine UT free of leap second adjustments.

Relativistic timescale analysis suggests lunar theory revision

NASA Technical Reports Server (NTRS)

Deines, Steven D.; Williams, Carol A.

1995-01-01

The SI second of the atomic clock was calibrated to match the Ephemeris Time (ET) second in a mutual four year effort between the National Physical Laboratory (NPL) and the United States Naval Observatory (USNO). The ephemeris time is 'clocked' by observing the elapsed time it takes the Moon to cross two positions (usually occultation of stars relative to a position on Earth) and dividing that time span into the predicted seconds according to the lunar equations of motion. The last revision of the equations of motion was the Improved Lunar Ephemeris (ILE), which was based on E. W. Brown's lunar theory. Brown classically derived the lunar equations from a purely Newtonian gravity with no relativistic compensations. However, ET is very theory dependent and is affected by relativity, which was not included in the ILE. To investigate the relativistic effects, a new, noninertial metric for a gravitated, translationally accelerated and rotating reference frame has three sets of contributions, namely (1) Earth's velocity, (2) the static solar gravity field and (3) the centripetal acceleration from Earth's orbit. This last term can be characterized as a pseudogravitational acceleration. This metric predicts a time dilation calculated to be -0.787481 seconds in one year. The effect of this dilation would make the ET timescale run slower than had been originally determined. Interestingly, this value is within 2 percent of the average leap second insertion rate, which is the result of the divergence between International Atomic Time (TAI) and Earth's rotational time called Universal Time (UT or UTI). Because the predictions themselves are significant, regardless of the comparison to TAI and UT, the authors will be rederiving the lunar ephemeris model in the manner of Brown with the relativistic time dilation effects from the new metric to determine a revised, relativistic ephemeris timescale that could be used to determine UT free of leap second adjustments.

UCAC3 PROPER MOTION SURVEY. I. DISCOVERY OF NEW PROPER MOTION STARS IN UCAC3 WITH 0.''40 yr{sup -1} > {mu} {>=} 0.''18 yr{sup -1} BETWEEN DECLINATIONS -90{sup 0} AND -47{sup 0}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finch, Charlie T.; Zacharias, Norbert; Henry, Todd J., E-mail: finch@usno.navy.mi

2010-09-15

This paper presents 442 new proper motion stellar systems in the southern sky between declinations -90{sup 0} and -47{sup 0} with 0.''40 yr{sup -1} > {mu} {>=} 0.''18 yr{sup -1}. These systems constitute a 25.3% increase in new systems for the same region of the sky covered by previous SuperCOSMOS RECONS (SCR) searches that used Schmidt plates as the primary source of discovery. Among the new systems are 25 multiples, plus an additional 7 new common proper motion (CPM) companions to previously known primaries. All stars have been discovered using the third U.S. Naval Observatory (USNO) CCD Astrograph Catalog (UCAC3).more » A comparison of the UCAC3 proper motions to those from the Hipparcos, Tycho-2, Southern Proper Motion (SPM4), and SuperCOSMOS efforts is presented and shows that UCAC3 provides similar values and precision to the first three surveys. The comparison between UCAC3 and SuperCOSMOS indicates that proper motions in R.A. are systematically shifted in the SuperCOSMOS data but are consistent in decl. data, while overall showing a significantly higher scatter. Distance estimates are derived for stars having SuperCOSMOS Sky Survey B{sub J} , R{sub 59F}, and I{sub IVN} plate magnitudes and Two-Micron All Sky Survey infrared photometry. We find 15 systems estimated to be within 25 pc, including UPM 1710-5300 our closest new discovery estimated at 13.5 pc. Such new discoveries suggest that more nearby stars are yet to be found in these slower proper motion regimes, indicating that more work is needed to develop a complete map of the solar neighborhood.« less

International VLBI Service for Geodesy and Astrometry 2004 Annual Report

NASA Technical Reports Server (NTRS)

Behrend, Dirk (Editor); Baver, Karen D. (Editor)

2005-01-01

Contents include the following: Combination Studies using the Cont02 Campaign. Coordinating Center report. Analysis coordinator report. Network coordinator report. IVS Technology coordinator report. Algonquin Radio observatory. Fortaleza Station report for 2004. Gilmore Creek Geophysical Observatory. Goddard Geophysical and Astronomical observatory. Hartebeesthoek Radio Astronomy Observatory (HartRAO). Hbart, Mt Pleasant, station report for 2004. Kashima 34m Radio Telescope. Kashima and Koganei 11-m VLBI Stations. Kokee Park Geophysical Observatory. Matera GGS VLBI Station. The Medicina Station status report. Report of the Mizusawa 10m Telescope. Noto Station Activity. NYAL Ny-Alesund 20 metre Antenna. German Antarctic receiving Station (GARS) O'higgins. The IVS network station Onsala space Observatory. Sheshan VLBI Station report for 2004. 10 Years of Geodetic Experiments at the Simeiz VLBI Station. Svetloe RAdio Astronomical Observatory. JARE Syowa Station 11-m Antenna, Antarctica. Geodetic Observatory TIGO in Concepcion. Tsukuba 32-m VLBI Station. Nanshan VLBI Station Report. Westford Antenna. Fundamental-station Wettzell 20m Radiotelescope. Observatorio Astroonomico Nacional Yebes. Yellowknife Observatory. The Bonn Geodetic VLBI Operation Center. CORE Operation Center Report. U.S. Naval Observatory Operation Center. The Bonn Astro/Geo Mark IV Correlator.

Multiband Study of Radio Sources of the Rcr Catalogue with Virtual Observatory Tools

NASA Astrophysics Data System (ADS)

Zhelenkova, O. P.; Soboleva, N. S.; Majorova, E. K.; Temirova, A. V.

We present early results of our multiband study of the RATAN Cold Revised (RCR) catalogue obtained from seven cycles of the ``Cold'' survey carried with the RATAN-600 radio telescope at 7.6 cm in 1980--1999, at the declination of the SS 433 source. We used the 2MASS and LAS UKIDSS infrared surveys, the DSS-II and SDSS DR7 optical surveys, as well as the USNO-B1 and GSC-II catalogues, the VLSS, TXS, NVSS, FIRST and GB6 radio surveys to accumulate information about the sources. For radio sources that have no detectable optical candidate in optical or infrared catalogues, we additionally looked through images in several bands from the SDSS, LAS UKIDSS, DPOSS, 2MASS surveys and also used co-added frames in different bands. We reliably identified 76% of radio sources of the RCR catalogue. We used the ALADIN and SAOImage DS9 scripting capabilities, interoperability services of ALADIN and TOPCAT, and also other Virtual Observatory (VO) tools and resources, such as CASJobs, NED, Vizier, and WSA, for effective data access, visualization and analysis. Without VO tools it would have been problematic to perform our study.

Optical spectroscopic followup of XMMSL1 J164303.7+653253 in the error box of IGR J16426+6536

NASA Astrophysics Data System (ADS)

Parisi, P.; Masetti, N.; Malizia, A.; Morelli, L.; Mason, E.; Dean, A. J.; Ubertini, P.

2008-10-01

We report on a spectroscopic observation of the optical object USNO-A2.0 1500-06133361 (with J2000 coordinates RA = 16 43 04.07, Dec = +65 32 50.9 and magnitude R ~ 18.9) inside the error circle of the XMM-Newton slew source XMMLS1 J164303.7+653253 (see Ibarra et al., ATel #1397), possibly associated with the unidentified INTEGRAL source IGR J16426+6536 (Bird et al. 2007, ApJS, 170, 175). The observations were performed on 2008 February 04, starting at 06:10 UT, with DOLORES, a focal reducer instrument installed on the 3.58m Telescopio Nazionale Galileo (TNG) in the Astronomical Observatory of Roque de Los Muchachos (Santa Cruz de La Palma, Spain), for a total exposure time of 1800 s.

Obituary: Ronald Cecil Stone, 1946-2005

NASA Astrophysics Data System (ADS)

Monet, Alice Kay Babcock

2006-12-01

Ronald C. Stone, an astronomer at the US Naval Observatory Flagstaff Station, passed away on 10 September 2005 in Downer's Grove, IL, following a valiant struggle with cancer. He was fifty-nine years old. Ron was born on 9 June 1946 in Seattle, Washington, to Helen (Vocelka) and Cecil Stone. His father was a World War II veteran who attended college on the GI Bill and became a mechanical engineer. He and his wife raised three sons: Dwight, Ronald, and Gavin. They lived in a number of locations across the U.S. before settling at last in Downer's Grove when Ron was in the fourth grade. Ron's interest in astronomy began when he was given a toy planetarium projector while still in grade school, and later a small telescope. In high school, he also built his own telescope, grinding the 6-inch mirror by hand. He completed grade school and high school in Downer's Grove and did his undergraduate studies at the University of Illinois at Urbana-Champaign, majoring in astronomy and physics and graduating cum laude in 1968. The following year, he was drafted into the U.S. Army and served for two years, including a stint in Vietnam. Although his primary assignment was auditing, he was also involved in the defense of the Long Binh base in Vietnam. He was honorably discharged from the service in 1971 and enrolled that fall at the University of Chicago. While a graduate student working with Bill van Altena, Ron developed his life long interest in the field of astrometry. Van Altena recalls him as "a quiet and cheerful student who wanted to learn, and [who] worked hard to understand the intricacies of astrometry... deriving the most precise proper motions from the 40-inch [Yerkes] refractor plates." Working at Yerkes Observatory in Williams Bay, Wisconsin, he completed a thesis entitled, "Mean Secular Parallax at Low Galactic Latitude." While living in Wisconsin, Ron also became engaged to Ellen Mickel, and the two were married at his parents' home in Downer's Grove. After earning his Ph.D. in 1978 from Chicago, Ron held a number of research and postdoctoral positions. These included a few months at the Venezuelan National Observatory in Merida, where he helped to set up an astrometric program. This work was unfortunately cut short because of difficulties obtaining the requisite work visa. He also had a two year postdoc at Northwestern University, where he did spectroscopy of massive stars and studied various open clusters. Ron and Ellen's first child, Heather, was born on 9 June 1981 in Evanston, IL. Ron and Ellen moved to Washington, DC, in 1981, where Ron joined the staff of the U.S. Naval Observatory Transit Circle Division. Their son, Geoffrey, was born on 10 May 1983. The marriage ended in divorce in 2001. During the three years that he spent at the USNO headquarters, Ron received training in observing and data reduction with the 6-inch transit circle. When in 1984 the observatory opened the Black Birch Station in New Zealand for surveying the southern sky with the 7-inch transit circle, Ron joined the first group of astronomers to transfer. There he became involved in developing software for the 7-inch, particularly with the image dissector and the acquisition and reduction of planetary observations. Together with Ellis Holdenreid, he worked on some aspects of the real time control software for the 7-inch. He also continued to work on his earlier interest in runaway OB stars. When Ron's tour at the Black Birch Station was coming to an end, he requested a transfer to the USNO Flagstaff Station in northern Arizona. There was a transit circle at the Flagstaff Station being fitted with a CCD camera, and Ron's experience with transit circles in Washington and Black Birch made him well-qualified to help with the modernization of this instrument. Ron worked with David and Alice Monet to automate the 8-inch and develop astrometric software for reducing and analyzing its observations. This telescope came to be known as the FASTT, for Flagstaff Astrometric Scanning Transit Telescope. It was used from 1992 onward to obtain highly accurate astrometric positions of various Solar System bodies that were targets of several NASA space missions. In addition, Ron observed astrometric calibration regions for the Sloan Digital Sky Survey. He collaborated in projects to predict and observe stellar and planetary occultations, determine the masses of certain asteroids, and improve the orbits of numerous planetary satellites. In his letter recalling Ron Stone's career, Bill van Altena wrote, "I also knew and respected Ron as a scientist who worked to do the very best that he could with the FASTT system and produced an outstanding set of data that will be remembered as setting the standards for the best that could be done with drift scanning astrometry." Ron used FASTT observations of radio stars and the brightest quasars to confirm the tie between the optical and radio reference frames. He developed extensive software for automated reduction of FASTT observations. During his last year of life, he took on the additional responsibility of bringing another new telescope, the 1.3-meter, into operation, and was making good progress in this effort until his illness forced him to relinquish the task. Besides his professional interests, Ron was a avid outdoorsman. During his years in Williams Bay, he rode a motorcycle and enjoyed SCUBA diving. He is one of the few people to have gone diving in Lake Geneva. He liked nothing better than hiking and exploring wilderness areas. As his brother, Dwight, recalled, "If he saw a mountain, he had to climb it!"

Measurements of Neglected Double Stars: February 2018 Report

NASA Astrophysics Data System (ADS)

Carro, Joseph M.

2018-07-01

This article presents measurements of 53 neglected double stars. The stars were selected from the Washington Double Star Catalog published by the United States Naval Observatory. The photographs were taken by remote telescopes. The measurements were done by the author.

The General History of Astronomy

NASA Astrophysics Data System (ADS)

Gingerich, Owen

2010-04-01

Foreword; Preface; Acknowledgements; Part I. The Birth of Astrophysics and Other Late Nineteenth-Century Trends (c.1850-c.1920); 1. The origins of astrophysics A. J. Meadows; 2. The impact of photography on astronomy John Lankford; 3. Telescope building, 1850-1900 Albert Van Helden; 4. The new astronomy A. J. Meadows; 5. Variable stars Helen Sawyer Hogg; 6. Stellar evolution and the origin of the Hertzsprung-Russell diagram David DeVorkin; Part II. Observatories and Instrumentation: 7. Astronomical institutions. Introduction Owen Gingerich, Greenwich Observatory Philip S. Laurie, Paris Observatory Jacques Lévy, Pulkovo Observatory Aleksandr A. Mikhailov, Harvard College Observatory Howard Plotkin, United States Naval Observatory Deborah Warner, Lick Observatory Trudy E. Bell, Potsdam Astrophysical Observatory Dieter B. Herrmann; 8. Building large telescopes, 1900-1950 Albert Van Helden; 9. Astronomical institutions in the southern hemisphere, 1850-1950 David S. Evans; 10. Twentieth-century instrumentation Charles Fehrenbach, with a section on 'Early rockets in astronomy' Herbert Friedman; 11. Early radio astronomy Woodruff T. Sullivan III; Appendix: The world's largest telescopes, 1850-1950 Barbara L. Welther; Illustrations: acknowledgements and sources; Index.

Comparing the Effectiveness of Online Sunrise/Sunset Calculators

NASA Astrophysics Data System (ADS)

Phlips, Alan; Wilson, Teresa; Chizek Frouard, Malynda; Bartlett, Jennifer Lynn

2018-01-01

The USNO is responsible for providing information through its website on various types of natural phenomena, including times of sunrise and sunset for any given day and location. Alternative websites were explored to see what options are available in case the USNO can no longer support this on-line tool in the future. Websites with sunrise/sunset calculators were examined to see what algorithm they cited, if any. A large percentage of the websites took their calculations from three main sources (USNO, Meeus, and Schlyter). For ease of comparison, one website with an Application Programming Interface (API) for each algorithm was used to generate sunrise/sunset times for 2 dates per year for 24 years at latitudes from the equator to each pole along the prime meridian. Additionally, dates on which only one phenomenon was expected (first and last day of polar day and night) were tested to examine how each algorithm would perform for these extreme edge cases. At mid-latitudes, all of the algorithms agreed within 1 minute of each other but their predictions began to diverge as they approached the poles. Close to the poles, all three differed by more than a minute. While the algorithms diverged well before reaching the poles, Schlyter did so at much lower latitudes compared to the other two. In the edge cases, Schlyter and Meeus did not correctly document the missing sunrise/sunsets. Until a set of arctic or antarctic observations of sunrise and sunset times can be analyzed, we cannot ascertain which algorithm is the most accurate. However, the USNO algorithm handled cases of continuous day and night better than the others. There currently seems to be no better alternative to provide robust sunrise/set times than the USNO Complete Sun and Moon Data for One Day (http://aa.usno.navy.mil/data/docs/RS_OneDay.php).

A Regional, Multi-Stakeholder Collaboration for Dark-Sky Protection in Flagstaff, Arizona

NASA Astrophysics Data System (ADS)

Hall, Jeffrey C.

2018-01-01

Flagstaff, Arizona is home to almost $200M in astronomical assets, including Lowell Observatory's 4.3-meter Discovery Channel Telescope and the Navy Precision Optical Interferometer, a partnership of Lowell, the U. S. Naval Observatory, and the Naval Research Laboratory. The City of Flagstaff and surrounding Coconino County have comprehensive and effective dark-sky ordinances, but continued regional growth has the potential to degrade the area's dark skies to a level at which observatory missions could be compromised. As a result, a wide array of stakeholders (the observatories, the City, the County, local dark-sky advocates, the business and tourism communities, the national parks and monuments, the Navajo Nation, the U. S. Navy, and others) have engaged in three complementary efforts to ensure that Flagstaff and Coconino County protect the area's dark skies while meeting the needs of the various communities and providing for continued growth and development. In this poster, I will present the status of Flagstaff's conversion to LED outdoor lighting, the Mission Compatibility Study carried out by the Navy to evaluate the dark-sky effects of buildout in Flagstaff, and the Joint Land Use Study (JLUS) presently underway among all the aforementioned stakeholders. Taken in sum, the efforts represent a comprehensive and constructive approach to dark-sky preservation region-wide, and they show what can be achieved when a culture of dark-sky protection is present and deliberate efforts are undertaken to maintain it for decades to come.

CCD Astrometric Measurements of WDS 08167+4053 Using the iTelescope Network

NASA Astrophysics Data System (ADS)

Riley, Bill; Li, Dewei; Li, Junyao; Dennis, Aren; Boyce, Grady; Boyce, Pat

2016-10-01

Separations and position angle astrometric measurements were made of the multiple star system WDS 08167+4053 AB, AC, and BC components. Our measurements compared favorably with historical measurements from the United States Naval Observatory Washington Double Star Catalog, confirming the trend.

SPECKLE INTERFEROMETRY AT THE U.S. NAVAL OBSERVATORY. XVI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, Brian D.; Hartkopf, William I.; Wycoff, Gary L., E-mail: bdm@usno.navy.mil, E-mail: wih@usno.navy.mil

2011-05-15

The results of 1031 speckle-interferometric observations of double stars, made with the 26 inch refractor of the U.S. Naval Observatory, are presented. Each speckle-interferometric observation of a system represents a combination of over two thousand short-exposure images. These observations are averaged into 457 mean relative positions and range in separation from 0.''15 to 16.''94, with a median separation of 3.''03. The range in V-band magnitudes for the primary (secondary) of observed targets is 3.1-12.9 (3.2-13.3). This is the sixteenth in a series of papers presenting measurements obtained with this system and covers the period 2009 January 12 through 2009 Decembermore » 17. Included in these data are 12 older measurements whose positions were previously deemed possibly aberrant, but are no longer classified this way following a confirming observation. Also, 10 pairs with a single observation are herein confirmed. This paper also includes the first data obtained using a new ICCD with fiber optic cables.« less

Multiyear Interactive Computer Almanac (MICA)

Science.gov Websites

from the U.S. Naval Observatory About MICA Features System Requirements Delta T File and Software Requirements | Delta T and Software Updates | FAQ and Bug Reports | Ordering ] Features MICA can perform the , and delta T). Twilight, rise, set, and transit times for major solar system bodies, selected bright

Notes on Estimating the Seamount Slope from Vertical Deflection.

DTIC Science & Technology

1981-09-01

Division. 37 L . ,-_:. ,- .r- ’ ,l " . .. - "A DISTRIBUTION Defense Mapping Agency Naval Observatory Building 56 ATTN: O.W. Williams C. Martin P. M...Environmental Laboratory ATTN: J. Apel M. Byrne Seattle, WA 98105 Aerospace Corporation 2350 East El Segundo Boulevard ATTN: Library El Segundo, CA 90245

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2004-12-01

325-332. [15] D. Kirchner, 1999, “Two Way Satellite Time and Frequency Transfer ( TWSTFT ),” Review of Radio Science (Oxford Science Publications...Time and Frequency Transfer ( TWSTFT ),” in Proceedings of the 36th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting, 7-9

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2007-11-01

Institute of Navigation, Alexandria, Virginia). [21] D. Kirchner, 1999, “Two Way Satellite Time and Frequency Transfer ( TWSTFT ),” Review of Radio Science...Transfer ( TWSTFT ),” in Proceedings of the 36th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting, 7-9 December 2004

Evaluation of a New Prototype Geodetic Astrolabe for Measuring Deflections of the Vertical

NASA Astrophysics Data System (ADS)

Slater, J. A.; Thompson, N.; Angell, L. E.; Belenkii, M. S.; Bruns, D. G.; Johnson, D. O.

2009-12-01

During the last three years, the National Geospatial-Intelligence Agency (NGA), with assistance from the U.S. Naval Observatory (USNO), sponsored the development of a new electronic geodetic astrolabe for measuring deflections of the vertical (DoV). NGA’s current operational astrolabes, built in 1995, have a number of undesirable features including the need for a pool of liquid mercury as a reflecting surface. The new state-of-the-art prototype instrument, completed by Trex Enterprises in early 2009, was designed to meet a 0.2 arcsec accuracy requirement. It reduces the weight, eliminates the mercury, and dramatically reduces observation times. The new astrolabe consists of a 101 mm aperture telescope with a 1.5° field of view and an inclinometer mounted inside a 92-cm high, 30-cm diameter tube, an external GPS receiver for timing, and a laptop computer that controls and monitors the instrument and performs the computations. Star images are recorded by an astronomical-grade camera with a 2,048 x 2,048 pixel CCD sensor that is externally triggered by time pulses from the GPS receiver. The prototype was designed for nighttime observation of visible stars equal to or brighter than magnitude 10.0. The inclinometer is a system of two orthogonal pendula that define the local gravitational vertical, each consisting of a brass plumb bob suspended from an aluminized polymer ribbon set between two electrodes. An internal reference collimator is rigidly tied to the inclinometer and projects an array of reference points of light onto the CCD sensor. After the astrolabe is coarsely leveled to within 20 arcsec, voice coil actuators automatically adjust and maintain the inclinometer vertical to within 0.02 arcsec. Independent images are collected at 6 second intervals using a 200 msec exposure time. The CCD coordinates are determined for each star and a collimator reference point on each image. Stars are identified by referencing a customized star catalog produced by USNO. A plate model is fitted to the topocentric coordinates of the stars, and then used to solve for the astronomical latitude and longitude of the vertical reference point on the CCD. The average of 100-150 individual image solutions (10-15 minutes) defines the astronomical position for the observation session. In order to remove an azimuthal orientation bias, the astrolabe is rotated 180°, a new observation session solution is produced for that orientation and then averaged with the first solution to get the final astronomical position of the site. By combining these coordinates with GPS-derived geodetic latitude and longitude, one obtains the DoV. Initial testing of the prototype at a known astronomic position has been completed. The tests evaluated the session-to-session and day-to-day repeatability of the solutions, the number of observations required for a solution, the accuracy with respect to the known position, and the operational robustness of the hardware and software. Based on the field tests, Trex will make improvements to the prototype hardware and software and then produce operational units for use by NGA.

High accuracy OMEGA timekeeping

NASA Technical Reports Server (NTRS)

Imbier, E. A.

1982-01-01

The Smithsonian Astrophysical Observatory (SAO) operates a worldwide satellite tracking network which uses a combination of OMEGA as a frequency reference, dual timing channels, and portable clock comparisons to maintain accurate epoch time. Propagational charts from the U.S. Coast Guard OMEGA monitor program minimize diurnal and seasonal effects. Daily phase value publications of the U.S. Naval Observatory provide corrections to the field collected timing data to produce an averaged time line comprised of straight line segments called a time history file (station clock minus UTC). Depending upon clock location, reduced time data accuracies of between two and eight microseconds are typical.

Relationships between U.S. Naval Observatory, LORAN-C and the Defense Satellite Communication System

NASA Technical Reports Server (NTRS)

Charron, L. G.

1982-01-01

The methods used in forming time scales for distant sites monitoring LORAN-C are addressed. The time transfers obtained via the defense satellite communication system (DSCS) and the data provided by this system used to calibrate these remote time scales are emphasized. The errors involved are discussed.

Speckle Interferometry at the U.S. Naval Observatory. XVIII

DTIC Science & Technology

2012-05-01

1 1.9 −0.03 Novakovic & Todorovic (2006) a Notes. a These are smallΔm system. The orbit indicates a quadrant flip is needed; however, based on...109, 332 Novakovic , B., & Todorovic, N. 2006, Serb. Astron. J., 172, 21 Popovic, G. M., & Pavlovic, R. 1996, Bull. Obs. Astron. Belgr., 153, 57 Scardia

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2008-12-01

USA (Institute of Navigation, Alexandria, Virginia). [22] D. Kirchner, 1999, “Two Way Satellite Time and Frequency Transfer ( TWSTFT ),” Review of...Shäfer, and A. Pawlitzki, 2005, “Development of Carrier- Phase-Based Two-Way Satellite Time and Frequency Transfer ( TWSTFT ),” in Proceedings of the 36th

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2007-01-01

Time and Frequency Transfer ( TWSTFT ),” Review of Radio Science (Oxford Science Publications), pp. 27-44. 14 38th Annual Precise Time and Time Interval...Fonville, D. Matsakis, W. Shäfer, and A. Pawlitzki, 2005, “Development of Carrier- Phase-Based Two-Way Satellite Time and Frequency Transfer ( TWSTFT

Automation of Precise Time Reference Stations (PTRS)

NASA Astrophysics Data System (ADS)

Wheeler, P. J.

1985-04-01

The U.S. Naval Observatory is presently engaged in a program of automating precise time stations (PTS) and precise time reference stations (PTBS) by using a versatile mini-computer controlled data acquisition system (DAS). The data acquisition system is configured to monitor locally available PTTI signals such as LORAN-C, OMEGA, and/or the Global Positioning System. In addition, the DAS performs local standard intercomparison. Computer telephone communications provide automatic data transfer to the Naval Observatory. Subsequently, after analysis of the data, results and information can be sent back to the precise time reference station to provide automatic control of remote station timing. The DAS configuration is designed around state of the art standard industrial high reliability modules. The system integration and software are standardized but allow considerable flexibility to satisfy special local requirements such as stability measurements, performance evaluation and printing of messages and certificates. The DAS operates completely independently and may be queried or controlled at any time with a computer or terminal device (control is protected for use by authorized personnel only). Such DAS equipped PTS are operational in Hawaii, California, Texas and Florida.

First orbital solution and evolutionary state for the newly discovered eclipsing binaries USNO-B1.0 1091-0130715 and GSC-03449-0680

NASA Astrophysics Data System (ADS)

Elkhateeb, M. M.; Nouh, M. I.; Nelson, R. H.

2015-02-01

A first photometric study for the newly discovered systems USNO-B1.0 1091-0130715 and GSC-03449-0680 was carried out by means of recent a windows interface version of the Wilson and Devinney code based on model atmospheres by Kurucz (1993). The accepted models reveal some absolute parameters for both systems, which are used in deriving the spectral type of the system components and their evolutionary status. Distances to each systems and physical properties were estimated. Comparisons of the computed physical parameters with stellar models are discussed. The components of the system USNO-B1.0 1091-0130715 and the primary of the system GSC-03449-0680 are found to be on or near the ZAMS track, while the secondary of GSC-03449-0680 system found to be severely under luminous and too cool compared to its ZAMS mass.

Speckle Interferometry at the US Naval Observatory. XIII

DTIC Science & Technology

2007-10-01

18443+3940 ............................. STF 2382 AB 6.394 348.9 2.35 1 0.3 0.06 Mason et al. (2004a) 0.2 0.03 Novakovic & Todorovic (2005) 18443+3940...1952, Bull. Astron. Paris, 16, 263 Novakovic , B., & Todorovic, N. 2005, Circ. d’Inf. 157 Olevic, D. 2002, Circ. d’Inf. 147 Olevic, D., & Cvetkovic, Z

The US Naval Observatory Zodiacal Zone Catalog (Douglas and Harrington 1990): Documentation for the machine-readable version

NASA Technical Reports Server (NTRS)

Warren, Wayne H., Jr.

1990-01-01

The machine readable version of the catalog, as it is currently being distributed from the Astronomical Data Center, is described. The Zodiacal Zone Catalog is a catalog of positions and proper motions for stars in the magnitude range where m sub v is between 4 and 10, lying within 16 deg of the ecliptic and north of declination -30 deg. The catalog contains positions and proper motions, at epoch, for equator and equinox J2000.0, magnitudes and spectral types taken mostly from the Smithsonian Astrophysical Observatory Star Catalog, and reference positions and proper motions for equinox and epoch B1950.0.

Father Secchi Goes to Washington

NASA Astrophysics Data System (ADS)

McCarthy, M. F.

1994-12-01

In 1848 a small group of Jesuit refugees arrived at Georgetown College near Washington, D.C. Among them was a young priest, Angelo Secchi, who had finished theology studies in Rome, but had not been able to complete his final examinations. This done successfully, Secchi turned to astronomy and the new facilities of the Georgetown College Observatory, directed by its founder, Fr. James Curley. During his two years in Washington, Secchi studied physics, wrote an article on Electrical Rheometry for the Smithsonian Institution, and formed a friendship with Matthew Fontaine Maury of the U.S. Navy, who headed the Chart Service and in 1844 was named superintendent of the National Observatory. This was later named the U.S. Naval Observatory. Secchi's friendships formed during the Washington visit proved most helpful for relations between European astronomers and U.S. colleagues. Secchi, after his return to Rome constructed the Observatory of the Collegio Romano atop the baroque Church of St. Ignatius in Rome and began his work in spectral classification of stars.

Common Proper Motion Companions to Nearby Stars: Ages and Evolution

DTIC Science & Technology

2008-11-01

supplying the stars with NIR magnitudes from 2MASS . This allowed Gould & Chaname (2004) to estimate, for the first time, trigonometric parallaxes of...sup- plemented by BVR optical photometry, mainly from USNO-B, and JHK near-IR photometry from 2MASS . This catalog covers the entire magnitude range...for the Schmidt plate data used in the USNO-B catalog, with possible local offsets up to about 300 mas. Systematic errors in UCAC2 and 2MASS are much

CCD observations of Phoebe, 9th satellite of Saturn

NASA Astrophysics Data System (ADS)

Fienga, A.; Arlot, J.-E.; Baron, N.; Bec-Borsenberger, A.; Crochot, A.; Emelyanov, N.; Thuillot, W.

2002-08-01

In 1998 and 1999, we started observations of the 9th satellite of Saturn. We made 163 observations using the 120 cm-telescope of Observatoire de Haute-Provence, France. We used the USNO A2 catalogue of stars for the astrometric reduction. With the help of observations of optical counterparts of ICRF sources, a zonal correction to the USNO A2.0 catalogue was computed and applied to the Phoebe positions. A comparison with the most recent theories was made.

New Binary Systems With Asymmetric Light Curves

NASA Astrophysics Data System (ADS)

Virnina, Natalia A.

2010-12-01

We present the results of investigation of the light curves of 27 newly discovered binary systems. Among the examined curves, there were 10 curves with statistically significant asymmetry of maximums, according the 3σ criterion for the difference between the maximal brightness. Half of these 10 curves have a higher first maximum, another half the second one. Two of these 10 curves, USNO-B1.0 1629-0064825 = VSX J052807.9+725606 and USNO-B1.0 1586-0116785, show the largest difference between magnitudes in maxima. The star VSX J052807.9+725606 also shows the secondary minimum, which is shifted from the phase φ = 0.5. The shape of the curve argues that the physical processes of this star could be close to that of well known short periodic binary system V361 Lyr, which has a spot on the surface of one star of the system. Another star, USNO-B1.0 1586-0116785, probably has a cold spot, or several spots, in the photosphere of one of the components.

The 2001 U.S. Naval Observatory Double Star CD-Rom. III. The Third Catalog of Interferometric Measurements of Binary Stars

DTIC Science & Technology

2001-12-01

CHARA southern speckle program from 1989 to 1996 (cf. Hartkopf et al. 1996), and by the more recent speckle e†orts of Horch and colleagues (cf. Horch ...Mason, B. D. 2001, Third Catalog of Interferometric Measurements of Binary Stars (CHARA Contrib. No. 4) (Atlanta : Georgia State Univ.) Horch , E

Speckle Interferometry at the U.S. Naval Observatory. 20th

DTIC Science & Technology

2015-10-06

W. 1936, MNRAS, 96, 266 [Mlb1936] Muterspaugh, M. W., Hartkopf, W. I., Lane, B. F., et al. 2010, AJ, 140, 1623 [Mut2010b] Novakovic , B. 2006, IAU...C26 Circ., 158 [Nov2006] Novakovic , B. 2008, Obs, 128, 56 [Nov2008b] Novakovic , B., & Todorovic, N. 2006, Serbian AJ, 172, 21 [Nov2006e] Olevic, D. 2002

J, H, K Spectro-Interferometry of the Mira Variable S Orionis

DTIC Science & Technology

2008-01-01

the Mira variable S Orionis M. Wittkowski1, D. A. Boboltz2, T. Driebe3, J.-B. Le Bouquin4 F. Millour3 K. Ohnaka3, and M. Scholz5,6 1 ESO, Karl ... Schwarzschild -Str. 2, 85748 Garching bei München, Germany e-mail: mwittkow@eso.org 2 US Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC

Future of Earth Orientation Predictions

DTIC Science & Technology

2010-01-01

introduced into the prediction process will increase . Potential drivers for change are discussed and possible directions for change are outlined. Keywords...is increasing as data latency has been reduced. However, all of these have been natural progressions; straightforward responses to improvements in...7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Naval Observatory,3450 Massachusetts Ave NW,Washington,DC,20392 8. PERFORMING ORGANIZATION

Imaging the Effects of Rotation in Altair and Vega

NASA Astrophysics Data System (ADS)

Peterson, D. M.; Hummel, C. A.; Pauls, T. A.; Armstrong, J. T.; Benson, J. A.; Gilbreath, C. G.; Hindsley, R. B.; Hutter, D. J.; Johnston, K. J.; Mozurkewich, D.

After a brief review of rotation among upper main sequence stars and von Zeipel's vZ24 theory for the interiors, we describe our interferometric measurements of two bright A stars, Altair and Vega. The Navy Prototype Optical Interferometer (jointly operated by the US Naval Observatory, the Naval Research Laboratory and Lowell Observatory) which works at visible wavelengths has implemented baselines of sufficient length to initiate true imaging of the disks of the brightest A stars. We report here measurements of Altair, the third brightest A star in the sky. "Closure phase" techniques show that Altair deviates dramatically from a normal limb-darkened isk, indicating a strongly asymmetric intensity distribution. A oche model provides a good fit to the data, indicating that Altair is rotating at about 90% of its breakup (angular) velocity. We find that a gravity darkening law exponent appropriate for a radiative star is required by the observations and we describe the potential of this object for testing the assumption of solid body rotation throughout its envelope. We will also describe recent measurements of Vega which confirm the proposed interpretation of spectral line measurements indicating that this star is also rapidly rotating, but seen nearly pole on.

Parallax Results from URAT Epoch Data

NASA Astrophysics Data System (ADS)

Finch, Charlie T.; Zacharias, Norbert

2016-06-01

We present 1103 trigonometric parallaxes and proper motions from the United States Naval Observatory Robotic Astrometric Telescope (URAT) observations taken at the Naval Observatory Flagstaff Station (NOFS) over a three-year period from 2012 April to 2015 June covering the entire sky north of about -10^\\circ decl. We selected two samples: previously suspected nearby stars from known photometric distances and stars showing a large, significant parallax signature in URAT epoch data without any prior selection criteria. All systems presented in this paper have an observed parallax ≥40 mas with no previous published trigonometric parallax. The formal errors on these weighted parallax solutions are mostly between 4 and 10 mas. This sample gives a significant (of the order of 50%) increase to the number of known systems having a trigonometric parallax to be within 25 pc of the Sun (without applying Lutz-Kelker bias corrections). A few of these are found to be within 10 pc. Many of these new nearby stars display a total proper motion of less than 200 mas yr-1. URAT parallax results have been verified against Hipparcos and Yale data for stars in common. The publication of all signifigant parallax observations from URAT data is in preparation for CDS.

John Quincy Adams's rhetorical crusade for astronomy.

PubMed

Portolano, M

2000-09-01

Astronomy thrived in Europe during the early nineteenth century, but in the United States a utilitarian mind-set opposed it. John Quincy Adams's oratory in support of American astronomical discovery reached its peak during congressional debate over the Smithsonian Institution (1838-1846). During this debate Adams countered proposals to found a university with plans for an observatory. His addresses to congressional and public audiences about observatories and astronomy were intended to foster interest in the science and encourage the growing astronomical community in America. Although the U.S. Naval Observatory in Washington, D.C., was established before the Smithsonian debate ended, many considered Adams its political father. Adams composed his speeches on astronomy in a systematic manner, following neoclassical principles of rhetoric that he had taught at Harvard University. His speeches both in and outside of Congress show evidence of the rhetorical principles he conscientiously used in the service of astronomy.

Possible new VY Scl-type variable 1RXS J075330.1+044606

NASA Astrophysics Data System (ADS)

Sokolovsky, K.; Denisenko, D.; Mescheryakov, A.; Tkachenko, A.; Korotkiy, S.; Gerke, V.

2012-02-01

We report the discovery of a possible new VY Scl-type cataclysmic variable associated with previously unidentified X-ray source 1RXS J075330.1+044606. The variable optical object USNO-B1.0 0947-0148659 (07:53:30.78 +04:45:56.3, J2000) located 15" from the X-ray source listed in the ROSAT All Sky Survey Faint Source Catalog (Voges et al., 2000, IAUC, 7432) was identified from information listed in the USNO-B1.0 catalog (Monet et al.

THE 'SPIROGRAPH' NEBULA

NASA Technical Reports Server (NTRS)

2002-01-01

THE 'SPIROGRAPH' NEBULA Glowing like a multi-faceted jewel, the planetary nebula IC 418 lies about 2,000 light-years from Earth in the direction of the constellation Lepus. This photograph is one of the latest from NASA's Hubble Space Telescope, obtained with the Wide Field Planetary Camera 2. A planetary nebula represents the final stage in the evolution of a star similar to our Sun. The star at the center of IC 418 was a red giant a few thousand years ago, but then ejected its outer layers into space to form the nebula, which has now expanded to a diameter of about 0.1 light-year. The stellar remnant at the center is the hot core of the red giant, from which ultraviolet radiation floods out into the surrounding gas, causing it to fluoresce. Over the next several thousand years, the nebula will gradually disperse into space, and then the star will cool and fade away for billions of years as a white dwarf. Our own Sun is expected to undergo a similar fate, but fortunately this will not occur until some 5 billion years from now. The Hubble image of IC 418 is shown in a false-color representation, based on Wide Field Planetary Camera 2 exposures taken in February and September, 1999 through filters that isolate light from various chemical elements. Red shows emission from ionized nitrogen (the coolest gas in the nebula, located furthest from the hot nucleus), green shows emission from hydrogen, and blue traces the emission from ionized oxygen (the hottest gas, closest to the central star). The remarkable textures seen in the nebula are newly revealed by the Hubble telescope, and their origin is still uncertain. Credit: NASA and The Hubble Heritage Team (STScI/AURA) Acknowledgment: Dr. Raghvendra Sahai (JPL) and Dr. Arsen R. Hajian (USNO). EDITOR'S NOTE: For additional information, please contact Dr. Raghvendra Sahai, Jet Propulsion Laboratory, MS 183-900, 4800 Oak Grove Drive, Pasadena, CA 91109, (phone) 818-354-0452, (fax) 818-393-9088, (e-mail) sahai@bb8.jpl.nasa.gov or Dr. Arsen R. Hajian, United States Naval Observatory, 3450 Massachusetts Ave, NW, Washington, DC 20392-5420, (phone) 202-762-1087, (fax) 202-762-1514, (e-mail) hajian.arsen@usno.navy.mil or Dr. Keith Noll, Space Telescope Science Institute, Baltimore, MD 21218, (phone) 410-338-1828, (fax) 410-338-4579, (e-mail) noll@stsci.edu. Electronic image files are available on the Internet at http://heritage.stsci.edu and http://oposite.stsci.edu/pubinfo/pr/2000/28 and via links in http://oposite.stsci.edu/pubinfo/latest.html http://oposite.stsci.edu/pubinfo/pictures.html and http://hubble.stsci.edu/go/news To receive STScI press releases electronically, send an Internet electronic mail message to public-request@stsci.edu. Leave the subject line blank. In the body of the message (not the subject line) type the word 'subscribe' (don't use quotes). The system will respond with a confirmation of the subscription, and you will receive new press releases as they are issued. Please subscribe using the email account with which you would like to receive list messages. To unsubscribe, send mail to public-request@stsci.edu. Leave the subject line blank. Type 'unsubscribe' (don't use quotes) in the body of the message. Please unsubscribe using the email account that you used to subscribe to the list.

GPS-UTC Time Synchronization

DTIC Science & Technology

1989-11-01

GPS-UTC TIME SYNCHRONIZATION C. H. MCKENZIE W. A. FEESS R, H. LUCAS H. HOLTZ A. L. SATIN The Aerospace Corporation El Segundo, California...Abstract Two automatic algorithms for synchronizing the GPS time standard to the UTC time standard are evaluated. Both algorithms control GPS-UTC...is required to synchronize its broadcast time standard to within one microsecond o f the time standard maintained by the US Naval Observatory

First results of GPS time transfer to Australia

NASA Technical Reports Server (NTRS)

Luck, J. M.; Woodger, J. R.; Wells, J. E.; Churchill, P. N.; Clements, P. A.

1985-01-01

A Global Positioning System time transfer unit built by NBS under contract to JPL was installed at Tidbinbilla Deep Space Communications Complex of the NASA Deep Space Network in June 1983. It has been used to estimate the relationship to UTC(USNO MC) of the Tidbinbilla frequency and time system TID(FTS) based on a hydrogen maser, and thence to estimate the performance of the Australian free-running time scale UTC(AUS). Data from the first three months has been analyzed three ways: by two-hop common view using JPL as intermediary; by long-arc interpolation of measurements against space vehicle clocks; and by long-arc interpolation of GPS-Time results. Residuals from a single quadratic fit through three months of UTC(USNO MC) - TID (FTS) results were white noise with standard error 15 ns, and a flying clock measurement gave 70 ns agreement. A straight line fit through results UTC(USNO MC) - UTC (AUS) gave 90 ns standard error and 120 bns agreement. It is proposed to use the GPS measurements to steer UTS(AUS) to UTC(BIH), and to rename the existing time scale TA(AUS).

First Results of GPS Time Transfer to Australia

NASA Technical Reports Server (NTRS)

Mck.luck, J.; Woodger, J. R.; Wells, J. E.; Churchill, P. N.; Clements, P. A.

1984-01-01

A global positioning system (GPS) time transfer unit was installed at Tidbinbilla Deep Space Communications Complex of the DSN in June 1983. It was used to estimate the relationship to UTC(USNO MC) of the Tidbinbilla frequency and time system TID(FTS) based on a hydrogen maser, and to estimate the performance of the Australian free-running time scale UTC(AUS). Data from the first 3 months were analyzed three ways: by two-hop common view using JPL as intermediary; by long-arc interpolation of measurements against space vehicle clocks; and by long arc interpolation of GPS-Time results. Residuals from a single quadratic fit through 3 months of UTC(USNO MC) -TID(FTS) results were white noise with standard error 15 ns, and a flying clock measurement gave 70 ns agreement. A straight line fit through results UTC(USNO MC) - UTC(AUS) gave 90 ns standard error and 120 ns agreement. It is proposed to use the GPS measurements to steer UTC(AUS) to UTC(BIH), and to rename the existing time scale TA(AUS).

Toward the ICRF3: Astrometric Comparison of the USNO 2016A VLBI Solution with ICRF2 and Gaia DR1

NASA Astrophysics Data System (ADS)

Frouard, Julien; Johnson, Megan C.; Fey, Alan; Makarov, Valeri V.; Dorland, Bryan N.

2018-06-01

The VLBI USNO 2016A (U16A) solution is part of a work-in-progress effort by USNO toward the preparation of the ICRF3. Most of the astrometric improvement with respect to the ICRF2 is due to the re-observation of the VCS sources. Our objective in this paper is to assess U16A’s astrometry. A comparison with ICRF2 shows statistically significant offsets of size 0.1 mas between the two solutions. While Gaia DR1 positions are not precise enough to resolve these offsets, they are found to be significantly closer to U16A than ICRF2. In particular, the trend for typically larger errors for southern sources in VLBI solutions is decreased in U16A. Overall, the VLBI-Gaia offsets are reduced by 21%. The U16A list includes 718 sources not previously included in ICRF2. Twenty of those new sources have statistically significant radio-optical offsets. In two-thirds of the cases, these offsets can be explained from PanSTARRS images.

U.S. Naval Observatory: The Move to Georgetown Heights and Double Star Work (1850-1950)

DTIC Science & Technology

2008-10-14

to Washington Headquarters Services , Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA...AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES Proceedings of the International ICOMOS Symposium in...Proceedings of the International ICOMOS Symposium in Hamburg, Oct. 14-17, 2008. 14. ABSTRACT Founded in 1830 as the Depot of Charts and Instruments, the

Nikolaev (Mykolayiv) Astronomical Observatory as the Object of the Ukrainian Tentative List WH UNESCO

NASA Astrophysics Data System (ADS)

Pinigin, Gennadiy; Pozhalova, Zhanna

2012-09-01

Nikolaev Astronomical Observatory (NAO), one of the oldest scientific institutions of the South-Eastern Europe, was founded as a naval observatory in 1821 for providing the needs of the Russian Black Sea Navy. It is a historical and astronomical complex with a reserved territory of total area 7.1 hectares, situated in the central part of Mykolaiv city, Ukraine. The beginning of scientific research at the Observatory is connected with the activity of Karl Knorre, its first director. From 1912 up to 1991, NAO was one of the Southern departments of Pulkovo Observatory with the main purpose to spread the system of absolute catalogs to the Southern hemisphere and to carry out regular observations of the Solar system bodies. Since 1992 NAO has become an independent leading institution of Ukraine in the field of positional astronomy, dynamics of Solar system bodies, research of near-Earth space, astronomical instrumentation. In 2007, it was inscribed in the Tentative UNESCO List of WH (#5116). The most significant part of the complex is the Main building, which was built in the style of Classicism in 1821--1829 (the monument of architecture #535 in the state registry). Also, the astronomical pavilions (1875, 1913, 1955, etc.) and instruments were preserved. Among them three Repsold instruments: meridian circle (1834), portable circle (1868) and vertical circle (1897). The unique astronomical and navigational devices, the collection of astronomical clocks are present in the observatory museum and the paper archive since the foundation of observatory is preserved.

MMS Observatory TV Results Contamination Summary

NASA Technical Reports Server (NTRS)

Rosecrans, Glenn; Brieda, Lubos; Errigo, Therese

2014-01-01

The Magnetospheric Multiscale (MMS) mission is a constellation of 4 observatories designed to investigate the fundamental plasma physics of reconnection in the Earth's magnetosphere. The various instrument suites measure electric and magnetic fields, energetic particles, and plasma composition. Each spacecraft has undergone extensive environmental testing to prepare it for its minimum 2 year mission. In this paper, we report on the extensive thermal vacuum testing campaign. The testing was performed at the Naval Research Laboratory utilizing the "Big Blue" vacuum chamber. A total of ten thermal vacuum tests were performed, including two chamber certifications, three dry runs, and five tests of the individual MMS observatories. During the test, the observatories were enclosed in a thermal enclosure known as the "hamster cage". The enclosure allowed for a detailed thermal control of various observatory zone, but at the same time, imposed additional contamination and system performance requirements. The environment inside the enclosure and the vacuum chamber was actively monitored by several QCMs, RGA, and up to 18 ion gauges. Each spacecraft underwent a bakeout phase, which was followed by 4 thermal cycles. Unique aspects of the TV campaign included slow pump downs with a partial represses, thruster firings, Helium identification, and monitoring pressure spikes with ion gauges. Selected data from these TV tests is presented along with lessons learned.

U.S. Naval Observatory Annual Report 2001-2002

DTIC Science & Technology

2002-06-01

practical astronomical information and data via printed publications, software products, and the World Wide Web. The Department’s products are used by the...Astronomical Almanac. Each almanac edition contains data for 1 year. These pub- lications are now on a well-established production schedule. The Astronomical...complementary Web site. In place of this list, the printed book will list the constants ~and references! used in the computations. Data for the obsolete Besselian

Time and Frequency Activities at The U.S. Naval Observatory

DTIC Science & Technology

2011-01-01

TWSTFT ) The most accurate means of operational long-distance time transfer is generally believed to be TWSTT [15-18], although the most precise...Frequency Transfer ( TWSTFT ),” Review of Radio Science (Oxford Science Publications), pp. 27-44. [16] L. A. Breakiron, A. L. Smith, B. C. Fonville...Matsakis, L. Breakiron, A. Bauch, D. Piester, D., and Z. Jiang, 2009, “Two-Way Satellite Time and Frequency ( TWSTFT ) Transfer Calibration Constancy from

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2010-01-01

TWSTT, ALSO REFERRED TO AS TWO-WAY SATELLITE TIME AND FREQUENCY TRANSFER ( TWSTFT ) The most accurate means of operational long-distance time...Frequency Transfer ( TWSTFT ),” Review of Radio Science (Oxford Science Publications), pp. 27-44. [25] L. A. Breakiron, A. L. Smith, B. C. Fonville, E...Breakiron, A. Bauch, D. Piester, D., and Z. Jiang, 2009, “Two-Way Satellite Time and Frequency ( TWSTFT ) Transfer Calibration Constancy from Closure

Time and Frequency Activities at the U.S. Naval Observatory

DTIC Science & Technology

2009-11-01

Massachusetts, USA (Institute of Navigation, Alexandria, Virginia). [22] D. Kirchner, 1999, “Two Way Satellite Time and Frequency Transfer ( TWSTFT ...Piester, D., and Z. Jiang, 2009, “Two-Way Satellite Time and Frequency ( TWSTFT ) Transfer Calibration Constancy from Closure Sums,” in Proceedings of...Shäfer, and A. Pawlitzki, 2005, “Development of Carrier- Phase-Based Two-Way Satellite Time and Frequency Transfer ( TWSTFT ),” in Proceedings of the 36 th

Legacy Bird Species at Risk Monitoring in and Around Camp Navajo and the Naval Observatory Flagstaff Station, AZ

DTIC Science & Technology

2010-04-16

19th century due to a convergence of complex stressors such as overgrazing, timber harvest, drought , and fire suppression (Allen et al. 2002, Moore... pinus 16 Olive Warbler Peucedramus taeniatus 5 Plumbeous Vireo Vireo solitarius 60 Pygmy Nuthatch Sitta pygmaea 177 Red Crossbill Loxia...Dove Zenaida macroura 14 Northern Flicker Colaptes auratus 50 Pine Siskin Carduelis pinus 58 Olive-sided Flycatcher Contopus cooperi 1

VizieR Online Data Catalog: The USNO-B1.0 Catalog (Monet+ 2003)

NASA Astrophysics Data System (ADS)

Monet, D. G.; Levine, S. E.; Casian, B.; et al.

2002-11-01

The USNO-B1.0 is a catalog that presents positions, proper motions, magnitudes in various optical passbands, and star/galaxy estimators for 1,045,913,669 objects derived from 3,648,832,040 separate observations. The data were taken from scans of 7,435 Schmidt plates taken from various sky surveys during the last 50 years. The catalog is expected to be complete down to V=21; the estimated accuracies are 0.2arcsec for the positions at J2000, 0.3mag in up to 5 colors, and 85% accuracy for distinguishing stars from non-stellar objects. (1 data file).

Astrometric Quality of the USNO CCD Astrograph (UCA)

NASA Astrophysics Data System (ADS)

Zacharias, N.

1997-05-01

The USNO 8-inch astrograph has been equipped with a Kodak 1536x1024 pixel CCD since June 1995, operating in a 570-650 nm bandpass. With 3-minute exposures well exposed images are obtained in the magnitude range R ~ 8.5 - 13.5(m) . An astrometric precision of 10 to 15 mas for those stars is estimated from frame-to-frame comparisons. External comparisons reveal an accuracy of about 15 mas for those stars in a 20' field of view. For fainter stars, the error budget is dominated by the S/N ratio, reaching ~ 100 mas at R=16(m) under good observing conditions.

Access To The PMM's Pixel Database

NASA Astrophysics Data System (ADS)

Monet, D.; Levine, S.

1999-12-01

The U.S. Naval Observatory Flagstaff Station is in the process of enabling access to the Precision Measuring Machine (PMM) program's pixel database. The initial release will include the pixels from the PMM's scans of the Palomar Observatory Sky Survey I (POSS-I) -O and -E surveys, the Whiteoak Extension, the European Southern Observatory-R survey, the Science and Engineering Council-J, -EJ, and -ER surveys, and the Anglo- Australian Observatory-R survey. (The SERC-ER and AAO-R surveys are currently incomplete.) As time allows, access to the POSS-II -J, -F, and -N surveys, the Palomar Infrared Milky Way Atlas, the Yale/San Juan Southern Proper Motion survey, and plates rejected by various surveys will be added. (POSS-II -J and -F are complete, but -N was never finished.) Eventually, some 10 Tbytes of pixel data will be available. Due to funding and technology limitations, the initial interface will have only limited functionality, and access time will be slow since the archive is stored on Digital Linear Tape (DLT). Usage of the pixel data will be restricted to non-commercial, scientific applications, and agreements on copyright issues have yet to be finalized. The poster presentation will give the URL.

The Chip-Scale Atomic Clock - Low-Power Physics Package

DTIC Science & Technology

2004-12-01

36th Annual Precise Time and Time Interval (PTTI) Meeting 339 THE CHIP-SCALE ATOMIC CLOCK – LOW-POWER PHYSICS PACKAGE R. Lutwak ...pdf/documents/ds-x72.pdf [2] R. Lutwak , D. Emmons, W. Riley, and R. M. Garvey, 2003, “The Chip-Scale Atomic Clock – Coherent Population Trapping vs...2002, Reston, Virginia, USA (U.S. Naval Observatory, Washington, D.C.), pp. 539-550. [3] R. Lutwak , D. Emmons, T. English, and W. Riley, 2004

NORDA’s Pattern Analysis Laboratory: Current Contributions to Naval Mapping, Charting, and Geodesy

DTIC Science & Technology

1989-04-01

magnetic observatories (McLeod, 1988). Using system integrates a suite of sensors and control devices the PAL’s VAX 11/780, spherical harmonic models to...DJAO:[FPS]*.OLB 5. Miscellaneous Utilities CALENDAR (NORDA events) 780 $ CALENDAR (menu-driven) DIALER modem controller 780 $ R AUTO DIAL:DIALER DTC...Utilities CALENDAR (NORDA events) 780 CALENDAR (menu-driven) DIALER modem controller 780 $ R AUTO DIAL:DIALER DTC Desk Top Calendar 780 $ DTC (menu-driven

Stereo Science Update

NASA Image and Video Library

2009-04-13

Michael Kaiser, project scientist, Solar Terrestrial Relations Observatory (STEREO) at Goddard Space Flight Center, left, makes a point during a Science Update on the STEREO mission at NASA Headquarters in Washington, Tuesday, April 14, 2009, as Angelo Vourlidas, project scientist, Sun Earth Connection Coronal and Heliospheric Investigation, at the Naval Research Laboratory, Toni Galvin, principal investigator, Plasma and Superthermal Ion Composition instrument at the University of New Hampshire and Madhulika Guhathkurta, STEREO program scientist, right, look on. Photo Credit: (NASA/Paul E. Alers)

Relative 2-color Photometry Of Neo's

NASA Astrophysics Data System (ADS)

Shelus, P.; Gyorgyey-Ries, J.; Ricklefs, R.; Barker, E.

We have been making Solar System small body positional observations at McDon- ald Observatory since the early 1970's. In 1994 we moved to a CCD-based, almost totally automated, astrometry system (Whipple et al, 1996, Astron. J., Vol. 112, p. 316). Our present observational effort is focussed upon Near Earth Objects (NEOs) as part of NASA's mission to discover and catalogue 90 percent of NEOs with diameters larger than 1 km by 2008. Observing 4 nights per lunation, we conduct observations to confirm newly discovered NEOs, filling in the night on a target-of-opportunnity basis, with observations of under-observed NEOs. Our major intent is to understand the overall hazard that these objects pose to Earth and their dynamical and physical characterization. We recently adopted the USNO-A2.0 catalogue to improve astromet- ric results and a number of up-grades to the end-to-end system have been developed (Barker et al, 2001, Bull. AAS, Vol. 33, p. 1116). The USNO catalog also provides stellar magnitudes in the standard Johnson R and B photometric bands. We have thus taken the opportunity to expand our observational efforts to regularly provide R mag- nitudes, in addition to astrometric positions. Our limiting magnitude in R is near 22. We are now furthering our photometric efforts by including B exposures as part of our standard observation triplet. We have already confirmed that switching filters between exposures on standard fields does not compromise the astrometric accurary. Thus, we plan to provide two color, sequential, relative photometry, (B-R), of newly discov- ered or under observed asteroids, as part of our routine observation process. The time interval between exposures is always less than 20 minutes, short compared to most asteroid rotation times. Consequently, a meaningful color index can be obtained in parallel with the astrometric positions. Although (B-R) is not the usual color index used in asteroid classification studies, we are testing whether we can use it as a quick diagnostic tool to roughly classify newly discovered NEOs. The results so far obtained are presented here. This research is funded by NASA's NEO Observation Program grants NAG5-6863 and NAG5-10183.

Barnard’s Star: Planets or Pretense

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Ianna, P. A.

2014-01-01

Barnard’s Star remains popular with planet hunters because it is not only an extremely near, high proper motion star, but also the object of early planet-detection claims. In 1963, van de Kamp explained perturbations in its proper motion by the presence of a planet. In 1969, he produced another single-planet solution and a two-planet solution to the astrometric wobbles detected. At least 19 studies have failed to confirm his results using a range of techniques, including radial velocity, direct imaging, and speckle interferometry. However, most of them lacked the sensitivity to detect the planets he described, including astrometric studies at the McCormick and Naval Observatories. However, radial-velocity monitoring of Barnard’s Star at Lick and Keck Observatories from 1987 through 2012 appears to have ruled out such planets. Based upon observations made at the Sproul Observatory between 1916 and 1962, van de Kamp claimed that Barnard’s Star had a planet with about 1.6 times the mass of Jupiter and an orbital period of 24 years. After accounting for instrumentation effects that might have been partially responsible for his initial results, he continued to assert that this red dwarf had two planets. In his 1982 analysis of ~20,000 exposures collected between 1938 and 1981, he calculated that two planets with 0.7- and 0.5-Jupiter masses in 12- and 20-year orbits, respectively, orbited the second-closest stellar system to our own. Starting in 1995, the dramatic successes of radial velocity searches for extrasolar planets drove van de Kamp’s unsubstantiated claims from popular consciousness. Although many low-mass stellar companions were discovered through astrometry, the technique has been less successful for planets: “The Extrasolar Planets Encyclopaedia” identifies one such discovery out of the 997 planets listed on 2013 September 23. Although Barnard’s Star has lost its pretensions to hosting the first extrasolar planets known, its intrinsic properties will keep it under observation. NSF grant AST 98-20711, Litton Marine Systems, Levinson Fund, University of Virginia, Hampden-Sydney College, and US Naval Observatory supported this research.

Frequency stability of on-orbit GPS Block-I and Block-II Navstar clocks

NASA Astrophysics Data System (ADS)

McCaskill, Thomas B.; Reid, Wilson G.; Buisson, James A.

On-orbit analysis of the Global Positioning System (GPS) Block-I and Block-II Navstar clocks has been performed by the Naval Research Laboratory using a multi-year database. The Navstar clock phase-offset measurements were computed from pseudorange measurements made by the five GPS monitor sites and from the U.S. Naval Observatory precise-time site using single or dual frequency GPS receivers. Orbital data was obtained from the Navstar broadcast ephemeris and from the best-fit, postprocessed orbital ephemerides supplied by the Naval Surface Weapons Center or by the Defense Mapping Agency. Clock performance in the time domain is characterized using frequency-stability profiles with sample times that vary from 1 to 100 days. Composite plots of Navstar frequency stability and time-prediction uncertainty are included as a summary of clock analysis results. The analysis includes plots of the clock phase offset and frequency offset histories with the eclipse seasons superimposed on selected plots to demonstrate the temperature sensitivity of one of the Block-I Navstar rubidium clocks. The potential impact on navigation and on transferring precise time of the degradation in the long-term frequency stability of the rubidium clocks is discussed.

Variability Analysis based on POSS1/POSS2 Photometry

NASA Astrophysics Data System (ADS)

Mickaelian, Areg M.; Sarkissian, Alain; Sinamyan, Parandzem K.

2012-04-01

We introduce accurate magnitudes as combined calculations from catalogues based on accurate measurements of POSS1- and POSS2-epoch plates. The photometric accuracy of various catalogues was established, and statistical weights for each of them have been calculated. To achieve the best possible magnitudes, we used weighted averaging of data from APM, MAPS, USNO-A2.0, USNO-B1.0 (for POSS1-epoch), and USNO-B1.0 and GSC 2.3.2 (for POSS2-epoch) catalogues. The r.m.s. accuracy of magnitudes achieved for POSS1 is 0.184 in B and 0.173 mag in R, or 0.138 in B and 0.128 in R for POSS2. By adopting those new magnitudes we examined the First Byurakan Survey (FBS) of blue stellar objects for variability, and uncovered 336 probable and possible variables among 1103 objects with POSS2-POSS1 >= 3σ of the errors, including 161 highly probable variables. We have developed methods to control and exclude accidental errors for any survey. We compared and combined our results with those given in Northern Sky Variability Survey (NSVS) database, and obtained firm candidates for variability. By such an approach it will be possible to conduct investigations of variability for large numbers of objects.

Department of Defense Precise Time and Time Interval program improvement plan

NASA Technical Reports Server (NTRS)

Bowser, J. R.

1981-01-01

The United States Naval Observatory is responsible for ensuring uniformity in precise time and time interval operations including measurements, the establishment of overall DOD requirements for time and time interval, and the accomplishment of objectives requiring precise time and time interval with minimum cost. An overview of the objectives, the approach to the problem, the schedule, and a status report, including significant findings relative to organizational relationships, current directives, principal PTTI users, and future requirements as currently identified by the users are presented.

Stereo Science Update

NASA Image and Video Library

2009-04-13

Michael Kaiser, project scientist, Solar Terrestrial Relations Observatory (STEREO) at Goddard Space Flight Center, left, makes a comment during a Science Update on the STEREO mission at NASA Headquarters in Washington, Tuesday, April 14, 2009, as Angelo Vourlidas, project scientist, Sun Earth Connection Coronal and Heliospheric Investigation, at the Naval Research Laboratory, second from left, Toni Galvin, principal investigator, Plasma and Superthermal Ion Composition instrument at the University of New Hampshire and Madhulika Guhathakurta, STEREO program scientist, right, look on. Photo Credit: (NASA/Paul E. Alers)

Stereo Science Update

NASA Image and Video Library

2009-04-13

Angelo Vourlidas, project scientist, Sun Earth Connection Coronal and Heliospheric Investigation, at the Naval Research Laboratory, second from left, makes a comment during a Science Update on the STEREO mission at NASA Headquarters in Washington, Tuesday, April 14, 2009, as Michael Kaiser, project scientist, Solar Terrestrial Relations Observatory (STEREO) at Goddard Space Flight Center, left, Toni Galvin, principal investigator, Plasma and Superthermal Ion Composition instrument at the University of New Hampshire and Madhulika Guhathakurta, STEREO program scientist, right, look on. Photo Credit: (NASA/Paul E. Alers)

GPS NAVSTAR-4 and NTS-2 Long Term Frequency Stability and Time Transfer Analysis.

DTIC Science & Technology

1980-06-30

delta pseudo-range, are taken every 6 s. NTS Tracking Network Figure 4 presents the four station network employed for tracking the NTS spacecraft. Thc ...limits of visibility for the NRL CBD (Chesapeake Bay Division), Panama, Australia, and Eng- land tracking stations are depicted by the symbols C, P...GIAT and, in Australia, with the Division of National Mapping. The CBD tracking station had port- able clock and TV links to the U.S. Naval Observatory

Physics of Bodily Tides in Terrestrial Planets and the Appropriate Scales of Dynamical Evolution

DTIC Science & Technology

2007-12-29

ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Naval Observatory ,3450 Massachusetts Ave,Washington,DC,20392-5420 8. PERFORMING ORGANIZATION REPORT NUMBER 9...circumstances only the principal tidal frequency (4) will matter . 2. Quality Factor Q and the Geometric Lag Angle d [7] During tidal flexure, the...correct. The inaccuracy in notations has not prevented Bills et al. [2005] from arriving at a reasonable value of the Martian quality factor, 85.58 ± 0.37

Astrometry of Pluto from 1930-1951 observations: The Lampland plate collection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buie, Marc W.; Folkner, William M., E-mail: buie@boulder.swri.edu, E-mail: william.m.folkner@jpl.nasa.gov

We present a new analysis of 843 photographic plates of Pluto taken by Carl Lampland at Lowell Observatory from 1930–1951. This large collection of plates contains useful astrometric information that improves our knowledge of Pluto's orbit. This improvement provides critical support to the impending flyby of Pluto by New Horizons. New Horizons can do inbound navigation of the system to improve its targeting. This navigation is capable of nearly eliminating the sky-plane errors but can do little to constrain the time of closest approach. Thus the focus on this work was to better determine Pluto's heliocentric distance and to determinemore » the uncertainty on that distance with a particular eye to eliminating systematic errors that might have been previously unrecognized. This work adds 596 new astrometric measurements based on the USNO CCD Astrograph Catalog 4. With the addition of these data the uncertainty of the estimated heliocentric position of Pluto in Developmental Ephemerides 432 (DE432) is at the level of 1000 km. This new analysis gives us more confidence that these estimations are accurate and are sufficient to support a successful flyby of Pluto by New Horizons.« less

Astrometry of Pluto from 1930-1951 Observations: the Lampland Plate Collection

NASA Astrophysics Data System (ADS)

Buie, Marc W.; Folkner, William M.

2015-01-01

We present a new analysis of 843 photographic plates of Pluto taken by Carl Lampland at Lowell Observatory from 1930-1951. This large collection of plates contains useful astrometric information that improves our knowledge of Pluto's orbit. This improvement provides critical support to the impending flyby of Pluto by New Horizons. New Horizons can do inbound navigation of the system to improve its targeting. This navigation is capable of nearly eliminating the sky-plane errors but can do little to constrain the time of closest approach. Thus the focus on this work was to better determine Pluto's heliocentric distance and to determine the uncertainty on that distance with a particular eye to eliminating systematic errors that might have been previously unrecognized. This work adds 596 new astrometric measurements based on the USNO CCD Astrograph Catalog 4. With the addition of these data the uncertainty of the estimated heliocentric position of Pluto in Developmental Ephemerides 432 (DE432) is at the level of 1000 km. This new analysis gives us more confidence that these estimations are accurate and are sufficient to support a successful flyby of Pluto by New Horizons.

VizieR Online Data Catalog: URAT Parallax Catalog (UPC) (Finch+, 2016)

NASA Astrophysics Data System (ADS)

Finch, C. T.; Zacharias, N.

2016-04-01

The URAT Parallax Catalog (UPC) consists of 112177 parallaxes. The catalog utilizes all Northern Hemisphere epoch data from the United States Naval Observatory (USNO) Robotic Astrometric Telescope (URAT). This data includes all individual exposures from April 2012 to June 2015 giving a larger epoch baseline for determining parallaxes over the 2-year span of the First USNO Robotic Astrometric Telescope Catalog (URAT1) (Zacharias et al., 2015, Cat. I/329) published data. The URAT parallax pipeline is custom code that utilizes routines from (Jao, C.-W., 2004, PhD thesis Georgia Stat), the JPL DE405 ephemeris and Green's parallax factor (Green, R.M., 1985, Spherical Astronomy) for determining parallaxes from a weighted least-squares reduction. The relative parallaxes have been corrected to absolute by using the distance color relation described in (Finch et. al, 2014, Cat. J/AJ/148/119) to determine a mean distance of all UCAC4 reference stars (R=8-16 mag) used in the astrometric reductions. Presented here are all significant parallaxes from the URAT Northern Hemisphere epoch data comprising of 2 groups: a) URAT parallax results for stars with prior published parallax, and b) first time trigonometric parallaxes as obtained from URAT data of stars without prior published parallax. Note, more stringent selection criteria have been applied to the second group than the first in order to keep the rate of false detections low. For specific information about the astrometric reductions please see 'The First U.S. Naval Observatory Robotic Astrometric Telescope Catalog' published paper (Zacharias et al., 2015AJ....150..101Z, Cat. I/329). For complete details regarding the parallax pipeline please see 'Parallax Results From URAT Epoch Data' (Finch and Zacharias, 2016, AJ, in press). This catalog gives all positions on the ICRS at Epoch J2014.0; it covers the magnitude range 6.56 to 16.93 in the URAT band-pass, with an average parallax precision of 4.3mas for stars having no known parallax and 10.8mas for stars matched to external parallax sources. This catalog covers the sky from about North of -12.75° declination. This catalog was matched with the Hipparcos catalog, Yale Parallax Catalog, (Finch & Zacharias, 2016, AJ, in press), MEarth (Dittmann et. al., 2014ApJ...784..156D) and the SIMBAD database to obtain known parallax and star names. For stars matched to SIMBAD using the automated search feature, only the parallaxes are given so no information on the parallax errors or source for the parallax are reported for those stars in this catalog. A flag is included to show which catalog or database the URAT parallax was matched with. Only the data from the first catalog that was matched is reported here according to the following priority list. This means for example, if a star was matched with Hipparcos, that information was used while possible other catalog data are not listed here. -------------------------------------------------------- # stars flg catalog -------------------------------------------------------- 53500 0 no catalog match 55549 1 Hipparcos 254 2 Yale Parallax Catalog 1041 3 Finch and Zacharias 2016 (UPM NNNN-NNNN) 1431 4 MEarth parallaxes 402 5 SIMBAD Database (w/parallax) -------------------------------------------------------- 112177 total number stars in catalog -------------------------------------------------------- Not all parallaxes from the URAT epoch data are included in this catalog. Only those data meeting the following criteria have been included. For the epoch data we only used data having a FWHM<=7.0pixel; amplitude between 500 and 30000ADU; sigma x,y <=90.0mas; number of observations >=20 and epoch span>=1.0 years. The limits imposed on individual image amplitude, image profile width (FWHM) and position fit errors (sigma) are set to not allow saturated stars, stars with too few photons or poorly determined positions to be used in the parallax solution. We present all URAT parallax solutions having a known parallax from an external data source regardless of the quality of the solution (srcflg=1-5). This was done for the user to better understand the limitations for determining parallaxes with the current URAT epoch data. For the remaining URAT parallaxes without a match to any published trigonometric parallax (srcflg=0) we only present a parallax solutions having: 1) a parallax error <=10mas 2) a parallax error <=1/4 the relative parallax 3) epoch span >=1.5 years 4) number of observations used >=30 5) fit sigma<=1.4 (unit weight) 6) average image elongation <1.1. All of these cuts have been implemented in an attempt to lower the number of possible erroneous parallax solutions entering our catalog. However, the URAT reduction process does not take provisions for close doubles (blended images) of arcsecond-level separations. Many of the parallaxes, particularly those with large mean elongation, large parallax error, large fit sigma and many rejected observations are possibly blended images leading to a higher chance of an erroneous parallax solutions. A visual inspection of all residual plots and real sky images would not be practical for the entire catalog. However, we have included information in the catalog to help the user to determine if a solution should be investigated further. (1 data file).

KIC 8462852: Maria Mitchell Observatory Photographic Photometry 1930 to 1985

NASA Astrophysics Data System (ADS)

Castelaz, Michael; Barker, Thurburn

2018-01-01

KIC 8462852 is an F3V star which decreased 20% in visual brightness twice from 5 to 20 days (Boyajian et al., 2016, MNRAS, 457, 3988) in 2011 and again in 2013. New observations show decreases of a few percent in May 2017 (Waagen 2017, AAVSO Alert Notice, 579), and reanalysis of Kepler data shows a variation of 928.25 days and 22 dimming events (Kiefer et al. 2017, accepted). Photometry from the All-Sky Automated Survey for Supernovae and the All-Sky Automated Survey (ASAS) indicate two brightening episodes and a steady decrease in magnitude of 6.3 +/- 1.4 mmag/yr (Simon et al 2017, accepted). Photometric studies from photographic plate collections include a light curve from 1338 Harvard College Observatory plates over the period 1890 to 1989 (Schaefer 2016, ApJ, 822, L34) that indicates KIC 8462852 is dimming 0.164 +/- 0.013 magnitudes per century. Hippke et al. (2016, ApJ, 825, 73) present B and V light curves from photometry from the Sonneberg Observatory photographic plate collection (Brauer and Fuhrmann 1992, Die Sterne, 68, 19) covering the period from 1934 to 1995. The light curve suggests less than 3% or 0.03 magnitude per century decrease in brightness, consistent with the ASAS light curve and Kepler data.Another consistent set of astronomical photographic plates with KIC 8462852 are in the Maria Mitchell Observatory (MMO) collection (Strelnitski 2009 in ASP Conference Series Vol. 410 p. 96). This collection is located in the Astronomical Photographic Data Archive at the Pisgah Astronomical Research Institute. We extracted the photographic magnitudes of KIC 8462852 from 743 plates from 1930 to 1988. We chose 8 nearby comparison stars within one spectral subclass and within 0.05 magnitudes of KIC 8462852, and not identified as variables. The photometry is calibrated to the USNO B filter, closest in bandpass to the emulsion wavelength sensitivity. The light curve of KIC 8462852 suggests a trend of about 0.1 +/- 0.07 magnitudes per century decrease, an obvious brightening event with B = 12.18 on 27 July 1935, and an obvious dimming event with B = 12.72 on 21 October 1978. For reference, one comparison star shows a trend of 0.07 mag/century decrease; others are within +/-0.05 mag/century.

The Guilford-Carleton Eclipse Expedition of 1900

NASA Astrophysics Data System (ADS)

English, Thomas R., III

2006-12-01

The solar eclipse of 1900 May 28 provided an opportunity for American astronomers to make observations from home soil, as the shadow tracked across the southeastern United States from New Orleans to Norfolk. Eclipse parties were scattered throughout the southern states, including large-scale scientific teams traveling to sites in Georgia and North Carolina. These major operations, staffed by groups from Yerkes, Princeton, USNO, and Lick, featured multiple observing programs and all the modern techniques they could manage. In addition to the major astrophysical endeavors, there were many smaller parties in the field in 1900 that resembled the more casual eclipse expeditions that were characteristic of a few decades before. In these efforts, relatively small groups of observers used modest instruments and made mostly visual observations, and the expedition was as much a social event as it was a scientific venture. One such group was the party from Carleton College and Guilford College that observed from a fruit farm in Southern Pines, NC. At the turn of the century, the Goodsell Observatory at Carleton College in Minnesota was an important regional astronomical facility that had provided weather and time data for over 20 years, and was the site of publication of Popular Astronomy, a widely circulated astronomical journal. At Guilford College, on the other hand, the astronomy course was taught by the school’s Treasurer, and there were no significant astronomical facilities. The presentation will explain how these two schools came to combine efforts to study the 1900 solar eclipse, and will summarize the events of the trip and the observations made. This research was supported in part by the Herbert C. Pollock Award of the Dudley Observatory.

TimeSet: A computer program that accesses five atomic time services on two continents

NASA Technical Reports Server (NTRS)

Petrakis, P. L.

1993-01-01

TimeSet is a shareware program for accessing digital time services by telephone. At its initial release, it was capable of capturing time signals only from the U.S. Naval Observatory to set a computer's clock. Later the ability to synchronize with the National Institute of Standards and Technology was added. Now, in Version 7.10, TimeSet is able to access three additional telephone time services in Europe - in Sweden, Austria, and Italy - making a total of five official services addressable by the program. A companion program, TimeGen, allows yet another source of telephone time data strings for callers equipped with TimeSet version 7.10. TimeGen synthesizes UTC time data strings in the Naval Observatory's format from an accurately set and maintained DOS computer clock, and transmits them to callers. This allows an unlimited number of 'freelance' time generating stations to be created. Timesetting from TimeGen is made feasible by the advent of Becker's RighTime, a shareware program that learns the drift characteristics of a computer's clock and continuously applies a correction to keep it accurate, and also brings .01 second resolution to the DOS clock. With clock regulation by RighTime and periodic update calls by the TimeGen station to an official time source via TimeSet, TimeGen offers the same degree of accuracy within the resolution of the computer clock as any official atomic time source.

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2016-03-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2014-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2015-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2012)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2012-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2013)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2013-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2017-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2018-06-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

MMS Observatory Thermal Vacuum Results Contamination Summary

NASA Technical Reports Server (NTRS)

Rosecrans, Glenn P.; Errigo, Therese; Brieda, Lubos

2014-01-01

The MMS mission is a constellation of 4 observatories designed to investigate the fundamental plasma physics of reconnection in the Earths magnetosphere. Each spacecraft has undergone extensive environmental testing to prepare it for its minimum 2 year mission. The various instrument suites measure electric and magnetic fields, energetic particles, and plasma composition. Thermal vacuum testing was conducted at the Naval Research Laboratory (NRL) in their Big Blue vacuum chamber. The individual spacecraft were tested and enclosed in a cryopanel enclosure called a Hamster cage. Specific contamination control validations were actively monitored by several QCMs, a facility RGA, and at times, with 16 Ion Gauges. Each spacecraft underwent a bakeout phase, followed by 4 thermal cycles. Unique aspects of the TV environment included slow pump downs with represses, thruster firings, Helium identification, and monitoring pressure spikes with Ion gauges. Various data from these TV tests will be shown along with lessons learned.

VizieR Online Data Catalog: The orbits of Jupiter's irregular satellites (Brozovic+, 2017)

NASA Astrophysics Data System (ADS)

Brozovic, M.; Jacobson, R. A.

2018-05-01

The large majority of astrometric observations originate from Earth-based telescopes, although there are a handful of observations of Himalia and Callirrhoe from the New Horizons spacecraft flyby of Jupiter. The modern Hipparcos Catalog (Perryman et al. 1997A&A...323L..49P) based astrometry is reported as positions in the ICRF. We convert the older measurements to the ICRF positions. The references to optical observations up to the year 2000 are documented in Jacobson (2000AJ....120.2679J). We continued to use the Jacobson (2000AJ....120.2679J) observational biases for the early measurements. We have since extended the data set with observations published in the Minor Planet Electronic Circulars (MPEC), the International Astronomical Union Circulars (IAUC), the Natural Satellites Data Center (NSDC) database (Arlot & Emelyanov 2009A&A...503..631A), the United States Naval Observatory Flagstaff Station catalog, and the Pulkovo Observatory database. (5 data files).

As Big and As Good As It Gets: The Large Monolithic Imager for Lowell Observatory's 4.3-m Discovery Channel Telescope

NASA Astrophysics Data System (ADS)

Massey, Philip; Dunham, E. W.; Bida, T. A.; Collins, P.; Hall, J. C.; Hunter, D. A.; Lauman, S.; Levine, S.; Neugent, K.; Nye, R.; Oliver, R.; Schleicher, D.; Zoonematkermani, S.

2013-01-01

The Large Monolithic Imager (LMI), a camera built at Lowell Observatory, is currently undergoing commissioning on Lowell's new 4.3-m Discovery Channel Telescope (DCT). At the heart of the LMI is the largest charge-coupled device (CCD) that can be built using current fabrication techniques, and the first of its kind to be made by e2v. The active area of the chip is 92.2mmx92.4mm, and has 6144 by 6160 15-micron pixels. Our choice of a single chip over a mosaic of smaller ones was inspired by the success of USNO in deploying a similarly ginormous device made by Semiconductor Technology Associates, Inc. There are some significant advantages that a (very!) large single CCD has over a mosaic of smaller ones. With a mosaic, one has to dither to fill in the gaps between the chips for complete areal coverage. This is not only costly in overhead, but it also poses a limitation in faint surface brightness studies, as the sky brightness is constantly changing during the dithering process. In addition, differences in the wavelength dependence of the DQE can lead to differences in the color terms from chip to chip in mosaics, requiring one to deal with each chip as a separate instrument (see the Local Group Galaxy photometry of Massey et al. 2006, AJ, 131, 2478). The LMI avoids these problems. The Discovery Channel Telescope is being built by Lowell Observatory in partnership with Discovery Communications. First light took place in May 2012. Institutional DCT partners include Boston University (in perpetuity), the University of Maryland, and the University of Toledo. More about the DCT can be found in the adjacent poster by Hall et al. The LMI has been made possible thanks to a National Science Foundation grant (AST-1005313). We are currently doing on-sky evaluation of the camera, as commissioning of the DCT progresses, determining color terms, photometric zero-points, astrometric characteristics, etc. We will present these results, along with technical details and many pretty pictures (!), in our poster.

The First U.S. Naval Observatory Robotic Astrometric Telescope Catalog

DTIC Science & Technology

2015-10-01

in the “info” folder. URAT1 covers almost the entire northern sky and most of the area δ �−15°, plus the far south area around Pluto . 2.3. Robotic...meeting acceptable quality standards. A total of 14 and 12 exposures of the Pluto field area taken on 2013 September 19 and 2014 September 06...for our project. 2MASS was used for near-IR photometry and as the first epoch of URAT1 proper motions. Bill Gray (Project Pluto ) is thanked for making

International time and frequency comparison using very long baseline interferometer

NASA Astrophysics Data System (ADS)

Hama, Shinichi; Yoshino, Taizoh; Kiuchi, Hitoshi; Morikawa, Takao; Sato, Tokuo

VLBI time comparison experiments using the Kashima station of the Radio Research Laboratory and the Richmond and Maryland Point stations of the U.S. Naval Observatory have been performed since April 1985. A precision of 0.2 ns for the clock offset and 0.2 ps/s for the clock rate have been achieved, and good agreement has been found with GPS results for clock offset. Much higher precision has been found for VLBI time and frequency comparison than that possible with conventional portable clock or Loran-C methods.

Bodily Tides near the 1:1 Spin-Orbit Resonance: Correction to Goldreich’s Dynamical Model

DTIC Science & Technology

2012-01-01

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) US Naval Observatory,Washington,DC,20392 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING...Besides, for a sufficiently large triaxiality, pseudosynchronism is impossible, no matter what dissipation model is used. Keywords Bodily tides...the expression (66) for 〈 d E/dt 〉P will vanish for W equal to Wstall = 12 π n e2 ( 1 + e 2 16 ) + O(e6) + O(i2/Q) + O(en t/Q). (67) No matter

The horizontal and vertical semi-diameters of the Sun observed at the Cape of Good Hope (1834 - 1887) and Paris (1837 - 1906): A report on work in progress

NASA Technical Reports Server (NTRS)

Smith, C.; Messina, D.

1981-01-01

Cape and Paris meridian observations of the solar limbs which permit an estimate to be made of the solar semi-diameter were surveyed, sampled, and compared with Greenwich and U.S. Naval Observatory observations. Significant systematic errors were found in the Paris work and have been correlated with changes of instruments and observers. Results from the Cape series indicate that work should continue on the compilation of data from Cape observations of the Sun.

Space Studies Board Annual Report 1994

NASA Technical Reports Server (NTRS)

1995-01-01

The following summaries of major reports are presented: (1) 'Scientific Opportunities in the Human Exploration of Space;' (2) 'A Space Physics Paradox;' (3) 'An Integrated Strategy for the Planetary Sciences;' and (4) 'ONR (Office of Naval Research) Research Opportunities in Upper Atmospheric Sciences.' Short reports on the following topics are also presented: life and microgravity sciences and the Space Station Program, the Space Infrared Telescope Facility and the Stratospheric Observatory for infrared astronomy, the Advanced X-ray Astrophysics Facility and Cassini Saturn Probe, and the utilization of the Space Station.

Multi-parameter observations in the Ibero-Moghrebian region: the Western Mediterranean seismic network (WM) and ROA GPS geodynamic network

NASA Astrophysics Data System (ADS)

Pazos, Antonio; Martín Davila, José; Buforn, Elisa; Gárate Pasquín, Jorge; Catalán Morollón, Manuel; Hanka, Winfried; Udías, Agustín.; Benzzeghoud, Mourad; Harnafi, Mimoun

2010-05-01

The plate boundary between Eurasia and Africa plates crosses the called "Ibero-Maghrebian" region from the San Vicente Cape (SW Portugal) to Tunisia including the South of Iberia, Alboran Sea, and northern Morocco and Algeria. In this area, the convergence, with a low rate, is accommodated over a wide and diffuse deformation zone, characterized by a significant and widespread moderate seismic activity [Buforn et al., 1995], and the occurrence of large earthquakes is separated by long time intervals. Since more than hundred years ago San Fernando Naval Observatory (ROA), in collaboration with other Institutes, has deployed different geophysical and geodetic equipment in the Southern Spain - North-western Africa area in order to study this broad deformation zone. Currently a Broad Band seismic net (Western Mediterranean, WM net) is deployed, in collaboration with other institutions, around the Gulf of Cádiz and the Alboran sea, with stations in the South of Iberia and in North Africa (at Spanish places and Morocco), together with the seismic stations a permanent geodetic GPS net is co-installed at the same sites. Also, other geophysical instruments have been installed: a Satellite Laser Ranging (SLR) station at San Fernando Observatory Headquarter, a Geomagnetic Observatory in Cádiz bay area and some meteorological stations. These networks have been recently improved with the deployment of a new submarine and on-land geophysical observatory in the Alboran island (ALBO Observatory), where a permanent GPS, a meteorological station were installed on land and a permanent submarine observatory in 50 meters depth was also deploy in last October (with a broad band seismic sensor, a 3 C accelerometer and a DPG). This work shows the present status and the future plans of these networks and some results.

Pulkovo Observatory - One of the Main Centers of Astronomical Education in Russia

NASA Astrophysics Data System (ADS)

Shakht, Natalia A.

2007-08-01

Since the beginning of the activity in 1839, Pulkovo observatory was an important center of the teaching of astronomy and geodesy in Russia. The first director of Pulkovo observatory W. Ja. Struve together with Pulkovo astronomers taught the topographers and specialists in geodesy and to naval officers the methods of geographic coordinates determinations. Pulkovo observatory was the center of the improvement of such specialists till 1928. Pulkovo astronomers lecture for students in the leading educational centers during many decades and at present and also lead the aspirants and researchers. The works of Pulkovo astronomers have been united in the known textbooks of astronomy and stellar astronomy with several re-editions. In 1957-1965 after the first launch of artificial satellite, many seminars and schools, which were dedicated to study of observations of artificial satellites and to the space geodesy have been organized at Pulkovo. Each year, about 10-15 thousands of guests visit Pulkovo. Our astronomers have the contact with the amateurs of astronomy in many countries and collect the information on their observations. More than 1,000,000 observations of asteroids and comets made by amateurs are collected with the scientific aims, particularly for the enlargement of the information about NEOs. Pulkovo astronomers lecture and give the practical lessons in ecological expeditions, which unite young people of various places of Russia.

Astronomy in Denver: Centenary of the 1918 total solar eclipse across Denver

NASA Astrophysics Data System (ADS)

Stencel, Robert E.

2018-06-01

Totality during the 2017 August 21 solar eclipse (Saros 145) traveled along a path across the United States similar to that which occurred for the eclipse on 1918 June 8 (Saros 126), but with a less west-northerly track. This placed Denver and its then new Chamberlin Observatory in the path of totality. Denver University astronomy Professor Herbert Howe offered use of the Chamberlin Observatory 20-inch f/15 refractor, with its Clark doublet lens and Saegmueller mounting, in service of eclipse-related research. In preparation for the eclipse, Professor Howe and assistants had spent the last three months of 1917, refurbishing mechanical aspects of the telescope. Edwin Frost, then Director of Yerkes Observatory expressed interest and made a reconnaissance visit to the area in September 1917, reporting results in the Feb. 1918 issue of Popular Astronomy ( http://adsabs.harvard.edu/abs/1918PA.....26R.103F ). Frank Schlesinger, then director of Allegheny Observatory, asked if he might attach a special camera for star photography to the telescope at the eclipse, to test displacement of stars, in order to test a prediction of relativity theory. Among the additional visiting astronomical luminaries present on that June day in 1918 were Annie J. Cannon (Harvard), John Duncan (Wellesley), Herbert R. Morgan (U.S. Naval Observatory) and Robert Trumpler (Berkeley). To learn the results of all this eclipse preparedness, you will need to attend my talk in order to get “the rest of the story” or visit our twitter feed at: https://twitter.com/Chamberlin_Obs .

A globally efficient means of distributing UTC time and frequency through GPS

NASA Technical Reports Server (NTRS)

Kusters, John A.; Giffard, Robin P.; Cutler, Leonard S.; Allan, David W.; Miranian, Mihran

1995-01-01

Time and frequency outputs comparable in quality to the best laboratories have been demonstrated on an integrated system suitable for field application on a global basis. The system measures the time difference between 1 pulse-per-second (pps) signals derived from local primary frequency standards and from a multi-channel GPS C/A receiver. The measured data is processed through optimal SA Filter algorithms that enhance both the stability and accuracy of GPS timing signals. Experiments were run simultaneously at four different sites. Even with large distances between sites, the overall results show a high degree of cross-correlation of the SA noise. With sufficiently long simultaneous measurement sequences, the data shows that determination of the difference in local frequency from an accepted remote standard to better than 1 x 10(exp -14) is possible. This method yields frequency accuracy, stability, and timing stability comparable to that obtained with more conventional common-view experiments. In addition, this approach provides UTC(USNO MC) in real time to an accuracy better than 20 ns without the problems normally associated with conventional common-view techniques. An experimental tracking loop was also set up to demonstrate the use of enhanced GPS for dissemination of UTC(USNO MC) over a wide geographic area. Properly disciplining a cesium standard with a multi-channel GPS receiver, with additional input from USNO, has been found to permit maintaining a timing precision of better than 10 ns between Palo Alto, CA and Washington, DC.

Data Mining for Double Stars in Astrometric Catalogs

NASA Astrophysics Data System (ADS)

Wycoff, Gary L.; Mason, Brian D.; Urban, Sean E.

2006-07-01

The US Naval Observatory has mined over 140 astrometric catalogs, including the Astrographic Catalogue and the Two Micron All Sky Survey, for measures of double stars. This resulted in 114,218 new measures of 47,007 different systems spanning 110 years; these are now included in the Washington Double Star catalog (WDS). This is the single largest data set ever added to the WDS. The measures are typically of wider pairs, most between 4" and 30" thus, their value in aiding orbit determination is limited. However, they have proven invaluable in the verification of systems and the determination of rectilinear motions of systems.

HUBBLE OBSERVES THE PLANET URANUS

NASA Technical Reports Server (NTRS)

2002-01-01

This NASA Hubble Space Telescope image of the planet Uranus reveals the planet's rings and bright clouds and a high altitude haze above the planet's south pole. Hubble's new view was obtained on August 14, 1994, when Uranus was 1.7 billion miles (2.8 billion kilometers) from Earth. These details, as imaged by the Wide Field Planetary Camera 2, were only previously seen by the Voyager 2 spacecraft, which flew by Uranus in 1986. Since then, none of these inner satellites has been further observed, and detailed observations of the rings have not been possible. Though Uranus' rings were discovered indirectly in 1977 (through stellar occultation observations), they have never before been seen in visible light through a ground-based telescope. Hubble resolves several of Uranus' rings, including the outermost Epsilon ring. The planet has a total of 11 concentric rings of dark dust. Uranus is tipped such that its rotation axis lies in the plane of its orbit, so the rings appear nearly face-on. Three of Uranus' inner moons each appear as a string of three dots at the bottom of the picture. This is because the picture is a composite of three images, taken about six minutes apart, and then combined to show the moons' orbital motions. The satellites are, from left to right, Cressida, Juliet, and Portia. The moons move much more rapidly than our own Moon does as it moves around the Earth, so they noticeably change position over only a few minutes. One of the four gas giant planets of our solar system, Uranus is largely featureless. HST does resolve a high altitude haze which appears as a bright 'cap' above the planet's south pole, along with clouds at southern latitudes (similar structures were observed by Voyager). Unlike Earth, Uranus' south pole points toward the Sun during part of the planet's 84-year orbit. Thanks to its high resolution and ability to make observations over many years, Hubble can follow seasonal changes in Uranus's atmosphere, which should be unusual given the planet's large tilt. Credit: Kenneth Seidelmann, U.S. Naval Observatory, and NASA These observations were conducted by a team led by Dr. Ken Seidelmann of the U.S. Naval Observatory as Principal Investigator. These images have been processed by Professor Douglas Currie and Mr. Dan Dowling in the Department of Physics at the University of Maryland. Other team members are Dr. Ben Zellner at Georgia Southern University, Dr. Dan Pascu and Mr. Jim Rhode at the U.S. Naval Observatory, and Dr. Ed Wells, Mr. Charles Kowal (Computer Science Corporation) and Dr. Alex Storrs of the Space Telescope Science Institute.

Commission 8: Astrometry

NASA Astrophysics Data System (ADS)

Evans, Dafydd Wyn; Zacharias, Norbert; Kumkova, Irina; Andrei, Alexandre; Brown, Anthony; Gouda, Naoteru; Popescu, Petre; Souchay, Jean; Unwin, Stephen; Zhu, Zi

2012-04-01

Gaia is continuing well with its development and construction and is expected to achieve parallax accuracies of about 10 to 300 μas for 6 to 20 mag. It is scheduled to launch in 2013. The ICRF2 was adopted by the IAU in 2009 as the new fundamental celestial reference frame. The UCAC project concluded with the publication of its 4th data release (all-sky, over 100 million stars). The JASMINE project will launch the Nano-JASMINE satellite in 2012 and continues with the development of its other satellites which will complement the Gaia project. The PPMXL (Heidelberg) and XPM (Ukraine) catalogues provide improved astrometric accuracies from new reductions of USNO-B (USNO-A) and 2MASS data. It is disappointing that the SIM project was cancelled during this triennium. It would have further complemented the above two satellite projects and would have gone even beyond Gaia in astrometric accuracy.

Digitization and Position Measurement of Astronomical Plates of Saturnian Satellites

NASA Astrophysics Data System (ADS)

Yan, D.; Yu, Y.; Zhang, H. Y.; Qiao, R. C.

2014-05-01

Using the advanced commercial scanners to digitize astronomical plates may be a simple and effective way. In this paper, we discuss the method of digitizing and astrometrically reducing six astronomical plates of Saturnian satellites, which were taken from the 1 m RCC (Ritchey Chretien Coude) telescope of Yunnan Observatory in 1988, by using the 10000XL scanner of Epson. The digitized images of the astronomical plates of Saturnian satellites are re-reduced, and the positions of Saturnian satellites based on the UCAC2 (The Second US Naval Observatory CCD Astrograph Catalog) catalogue are given. A comparison of our measured positions with the IMCCE (Institut de Mecanique Celeste et de Calcul des Ephemerides) ephemeris of Saturnian satellites shows the high quality of our measurements, which have an accuracy of 106 mas in right ascension and 89 mas in declination. Moreover, our measurements appear to be consistent with this ephemeris within only about 56 mas in right ascension and 9 mas in declination.

Investigating Near Space Interaction Regions: Developing a Remote Observatory

NASA Astrophysics Data System (ADS)

Gallant, M.; Mierkiewicz, E. J.; Oliversen, R. J.; Jaehnig, K.; Percival, J.; Harlander, J.; Englert, C. R.; Kallio, R.; Roesler, F. L.; Nossal, S. M.; Gardner, D.; Rosborough, S.

2016-12-01

The Investigating Near Space Interaction Regions (INSpIRe) effort will (1) establish an adaptable research station capable of contributing to terrestrial and planetary aeronomy; (2) integrate two state-of-the-art second generation Fabry-Perot (FP) and Spatial Heteorodyne Spectrometers (SHS) into a remotely operable configuration; (3) deploy this instrumentation to a clear-air site, establishing a stable, well-calibrated observatory; (4) embark on a series of observations designed to contribute to three major areas of geocoronal research: geocoronal physics, structure/coupling, and variability. This poster describes the development of the INSpIRe remote observatory. Based at Embry-Riddle Aeronautical University (ERAU), initiative INSpIRe provides a platform to encourage the next generation of researchers to apply knowledge gained in the classroom to real-world science and engineering. Students at ERAU contribute to the INSpIRe effort's hardware and software needs. Mechanical/optical systems are in design to bring light to any of four instruments. Control software is in development to allow remote users to control everything from dome and optical system operations to calibration and data collection. In April 2016, we also installed and tested our first science instrument in the INSpIRe trailer, the Redline DASH Demonstration Instrument (REDDI). REDDI uses Doppler Asymmetric Spatial Heterodyne (DASH) spectroscopy, and its deployment as part of INSpIRe is a collaborative research effort between the Naval Research Lab, St Cloud State University, and ERAU. Similar to a stepped Michelson device, REDDI measures oxygen (630.0 nm) winds from the thermosphere. REDDI is currently mounted in a temporary location under INSpIRe's main siderostat until its entrance optical system can be modified. First light tests produced good signal-to-noise fringes in ten minute integrations, indicating that we will soon be able to measure thermospheric winds from our Daytona Beach testing site. Future work will involve installation and software integration of FP and SHS systems and the Embry-Riddle Instrument Control System. The INSpIRe project is funded through NSF-CAREER award AGS135231 and the NASA Planetary Solar System Observations Program. The REDDI instrument was supported by the Chief of Naval Research.

A real-time prediction of UTC

NASA Technical Reports Server (NTRS)

Thomas, Claudine; Allan, David W.

1994-01-01

The reference time scale for all scientific and technologic applications on the Earth, the Universal Coordinated Time (UTC), must be as stable, reliable, and accurate as possible. With this in view the BIPM and before it the BIH, have always calculated and then disseminated UTC with a delay of about 80 days. There are three fundamental reasons for doing this: (1) It takes some weeks for data, gathered from some 200 clocks spread world-wide, to be collected and for errors to be eliminated; (2) changes in clock rates can only be measured with high precision well after the fact; and (3) the measurement noise originating in time links, in particular using Loran-C, is smoothed out only when averaging over an extended period. Until mid-1992, the ultimate stability of UTC was reached at averaging times of about 100 days and corresponded to an Allan deviation sigma(sub y)(tau) of about 1,5x10(exp -14) then compared to the best primary clock in the world, the PTB CS2. For several years now, a predicted UTC has been computed by the USNO through an extrapolation of the values as published in deferred time by the BIPM. This is made available through the USNO Series 4, through the USNO Automated Data Service, and through GPS signals. Due to the instability of UTC, the poor predictability of the available clocks, and the intentional SA degradation of GPS signals, the real-time access to this extrapolated UTC has represented the true deferred-time UTC only to within several hundreds of nanoseconds.

A Pilot Study of the Kinematics of the Open Cluster IC 4756.

NASA Astrophysics Data System (ADS)

Upgren, A. R.; Lee, J. T.; Weis, E. W.

1998-12-01

In 1982 a working group of I.A.U. Commission 24 was established in order to provide parallax standard fields (IAU Transactions, XVIIIB,127 1982). Three of these fields for regular trigonometric parallax observation are centered on open clusters; the Pleiades, Praesepe and IC4756. Very few studies on IC4756 have been made; one is by Herzog and Sanders (AAPS, 19, 211 1975). The Van Vleck Observatory began normal parallax observations of IC4756 with its 0.5m astrometric refractor in 1980. A few observations were also obtained in 1963. Using Yale PDS machine, Lee has measured two of these early plates and two from 1997-98. The proper motion differences among the stars from different plate pair solutions are about 0.0008"/yr, and the mean proper motion of member stars is about 0.003"/yr, with respect to the mean motion of the field stars. The epoch difference of 34 years appears sufficient for accurate measures of the internal motion of the member stars. This cluster has also been observed with the 1.5m reflector of the U.S. Naval Observatory and the 0.65m McCormick Observatory refractor. These observations may also become available for the motion study.

Radio-Optical Reference Frame Link Using the U.S. Naval Observatory Astrograph and Deep CCD Imaging

NASA Astrophysics Data System (ADS)

Zacharias, N.; Zacharias, M. I.

2014-05-01

Between 1997 and 2004 several observing runs were conducted, mainly with the CTIO 0.9 m, to image International Celestial Reference Frame (ICRF) counterparts (mostly QSOs) in order to determine accurate optical positions. Contemporary to these deep CCD images, the same fields were observed with the U.S. Naval Observatory astrograph in the same bandpass. They provide accurate positions on the Hipparcos/Tycho-2 system for stars in the 10-16 mag range used as reference stars for the deep CCD imaging data. Here we present final optical position results of 413 sources based on reference stars obtained by dedicated astrograph observations that were reduced following two different procedures. These optical positions are compared to radio very long baseline interferometry positions. The current optical system is not perfectly aligned to the ICRF radio system with rigid body rotation angles of 3-5 mas (= 3σ level) found between them for all three axes. Furthermore, statistically, the optical-radio position differences are found to exceed the total, combined, known errors in the observations. Systematic errors in the optical reference star positions and physical offsets between the centers of optical and radio emissions are both identified as likely causes. A detrimental, astrophysical, random noise component is postulated to be on about the 10 mas level. If confirmed by future observations, this could severely limit the Gaia to ICRF reference frame alignment accuracy to an error of about 0.5 mas per coordinate axis with the current number of sources envisioned to provide the link. A list of 36 ICRF sources without the detection of an optical counterpart to a limiting magnitude of about R = 22 is provided as well.

150 Years of the American Nautical Almanac Office

NASA Astrophysics Data System (ADS)

Dick, S. J.

1999-05-01

In 1849, 50 years before the founding of the American Astronomical Society, the American Nautical Almanac Office was established in Cambridge, Massachusetts. Although the British had published a Nautical Almanac since 1767, both patriotic and practical reasons lay behind the founding of an American Nautical Almanac Office in the context of the growth of science in the United States. Lt. Charles Henry Davis served as the first Superintendent. In 1866 the Office moved to Washington, D. C., and beginning in 1893 it was physically located at the new (present) site of the U. S. Naval Observatory, of which it became a part over the next few years, and where it has since remained. >From its beginning the work of the Office was much broader than the publication of data for navigation. The Office also sought to improve the theories of motion of the Sun, Moon and planets, and the astronomical constants on which the Almanac was based. Under Simon Newcomb, Superintendent of the Office from 1877 until his retirement in 1897, a consistent system of constants was devised; some of these constants remained unchanged until 1984. The American Nautical Almanac Office was dominated before World War II by its Directors William S. Eichelberger (1910-1929) and A. James Robertson (1929-1939). During the War years Wallace J. Eckert introduced punched card techniques to the Office. Gerald Clemence used these techniques to improve planetary theories during his years as Director (1945-1958), and also ushered in the era of the electronic computer for both research and production. International collaboration was a hallmark of the tenures of Clemence, Edgar Woolard, Raynor Duncombe and P. K. Seidelmann, who also implemented changes necessitated by the Space Age. Since 1990 the Nautical Almanac Office has been part of the Astronomical Applications Department of the Naval Observatory.

Radio-optical reference frame link using the U.S. Naval observatory astrograph and deep CCD imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zacharias, N.; Zacharias, M. I., E-mail: nz@usno.navy.mil

2014-05-01

Between 1997 and 2004 several observing runs were conducted, mainly with the CTIO 0.9 m, to image International Celestial Reference Frame (ICRF) counterparts (mostly QSOs) in order to determine accurate optical positions. Contemporary to these deep CCD images, the same fields were observed with the U.S. Naval Observatory astrograph in the same bandpass. They provide accurate positions on the Hipparcos/Tycho-2 system for stars in the 10-16 mag range used as reference stars for the deep CCD imaging data. Here we present final optical position results of 413 sources based on reference stars obtained by dedicated astrograph observations that were reducedmore » following two different procedures. These optical positions are compared to radio very long baseline interferometry positions. The current optical system is not perfectly aligned to the ICRF radio system with rigid body rotation angles of 3-5 mas (= 3σ level) found between them for all three axes. Furthermore, statistically, the optical-radio position differences are found to exceed the total, combined, known errors in the observations. Systematic errors in the optical reference star positions and physical offsets between the centers of optical and radio emissions are both identified as likely causes. A detrimental, astrophysical, random noise component is postulated to be on about the 10 mas level. If confirmed by future observations, this could severely limit the Gaia to ICRF reference frame alignment accuracy to an error of about 0.5 mas per coordinate axis with the current number of sources envisioned to provide the link. A list of 36 ICRF sources without the detection of an optical counterpart to a limiting magnitude of about R = 22 is provided as well.« less

Analytical studies of NGC 1193

NASA Astrophysics Data System (ADS)

Tadross, A. L.

2005-01-01

The photometric data of Kalu\\dot{z}ny (1988) was used in conjunction with the proper motion measurements of USNO-B1.0 catalog (Monet et al. 2003) to refine and complete the main physical properties of the faint open cluster NGC 1193.

Pluto’s Atmosphere from the 23 June 2011 Stellar Occultation: Airborne and Ground Observations

NASA Astrophysics Data System (ADS)

Person, Michael J.; Bosh, A. S.; Levine, S. E.; Gulbis, A. A. S.; Zangari, A. M.; Zuluaga, C. A.; Dunham, E. W.; Pasachoff, J. M.; Babcock, B. A.; Pandey, S.; Armhein, D.; Sallum, S.; Tholen, D. J.; Collins, P.; Bida, T.; Taylor, B.; Wolf, J.; Meyer, A.; Pfueller, E.; Wiedermann, M.; Roesser, H.; Lucas, R.; Kakkala, M.; Ciotti, J.; Plunkett, S.; Hiraoka, N.; Best, W.; Pilger, E. L.; Miceli, M.; Springmann, A.; Hicks, M.; Thackeray, B.; Emery, J.; Rapoport, S.; Ritchie, I.

2012-10-01

The double stellar occultation by Pluto and Charon of 2011 June 23 was observed from numerous ground stations as well as the Stratospheric Observatory for Infrared Astronomy (SOFIA). This first airborne occultation observation since 1995 resulted in the best occultation chords recorded for the event, in three optical wavelength bands. The data obtained from SOFIA were combined with chords obtained from the ground at the IRTF (including a full spectral light curve), the USNO--Flagstaff Station, and Leeward Community College to give a detailed profile of Pluto’s atmosphere. The data show a return to the distinct upper and lower atmospheric regions with a knee, or kink in the light curves separating them as was observed in 1988 (Millis et al. 1993), rather than the smoothly transitioning bowl-shaped light curves of recent years (Elliot et al. 2007). We analyze the upper atmosphere by fitting a model to all of the light curves obtained, resulting in a half-light radius of 1288 ± 1 km. We analyze the lower atmosphere with two different methods to provide results under the separate assumptions of particulate haze and a strong thermal gradient. Results indicate that the lower atmosphere evolves on short seasonal timescales, changing between 1988 and 2006, and then returning to approximately the 1988 state in 2011, though at significantly higher pressures. Throughout these changes, the upper atmosphere remains remarkably stable in structure, again excepting the overall pressure changes. No evidence of the onset of atmospheric collapse predicted by frost migration models is yet seen, and the atmosphere appears to be remaining at a stable pressure level. This work was supported in part by NASA Planetary Astronomy grants to MIT (NNX10AB27G) and Williams College (NNX08AO50G, NNH11ZDA001N), as well as grants from USRA (#8500-98-003) and Ames Research (#NAS2-97-01) to Lowell Observatory.

Publications of the United States Naval Observatory. Second Series, Volume 26, Part 2. Results of Observations Made with the Seven-Inch Transit Circle 1967-1973

DTIC Science & Technology

1992-01-01

Sp R A 1950.0 to Na Epowha Ded 1950.0 e N6 Epoch6 P14 GC N30 No* 20448 -1 5611 8.8 F8 211214659 001 2 72.210 - f55� 0!15 2 72-210 16655 20449 -18...18077 22461 -67 3966 8.4 K0 25 09.422 0.14 3 69.520 -67 11 04.15 0.01 3 69.520 20449 22462 -27 16325 7.8 PS 23 25 18.104 0.07 4 70.926 -264346.34 0.10 4

Speckle Interferometry at the U.S. Naval Observatory. 19th

DTIC Science & Technology

2013-09-01

Hartkopf & Mason (2011b) 02563+7253 STF 312 12.850 46.2 1.73 2 1.4 −0.08 Cvetkovic & Novakovic (2006) 02592+2120 STF 333 12.066 209.1 1.35 1 −0.4 −0.01...0.2 −0.17 Mason et al. (2004b) 0.4 −0.11 Novakovic & Todorovic (2006) 18443+3940 STF 2383 CD 12.628 77.6 2.26 2 0.6 −0.12 Docobo & Costa (1984) 18489...Carnegie Inst.) Cvetkovic, Z., & Novakovic , B. 2006, SerAJ, 173, 73 DeRosa, R. J., Patience, J., Vigan, A., et al. 2012, MNRAS, 422, 2765 Docobo, J. A

Principles of Celestial Navigation: An Online Resource for Introducing Practical Astronomy to the Public

NASA Astrophysics Data System (ADS)

Urban, Sean E.

2015-08-01

Astronomy is often called a "gateway" science because it inspires appreciation and awe among children and non-scientists. Applied astronomy, with practical, real-world applications, can entice even the most utilitarian people to take notice and learn about the subject. Traditional celestial navigation is an astronomy topic that captures the attention of the public. The U.S. Naval Observatory has led the development of a publicly available online celestial navigation educational module titled, "Principles of Celestial Navigation". It can be used world-wide to introduce people to astronomy. This poster describes some of the aspects of this teaching module.

Long-term comparisons between two-way satellite and geodetic time transfer systems.

PubMed

Plumb, John F; Larson, Kristine M

2005-11-01

Global Positioning System (GPS) observations recorded in the United States and Europe were used to evaluate time transfer capabilities of GETT (geodetic time transfer). Timing estimates were compared with two-way satellite time and frequency transfer (TWSTFT) systems. A comparison of calibrated links at the U.S. Naval Observatory, Washington, D.C., and Colorado Springs, CO, yielded agreement of 2.17 ns over 6 months with a standard deviation of 0.73 ns. An uncalibrated link between the National Institute of Standards and Technology (NIST) and Physikalisch-Technische Bundesanstalt, Braunschweig, Germany, has a standard deviation of 0.79 ns over the same time period.

New phone-in time service

NASA Astrophysics Data System (ADS)

If you want to know the precise time—in fact, the most precise time available—call 1-900-410-TIME. This will connect you with the U.S. Naval Observatory's Master Clock in Washington, D.C., keeper of the national time standard, where a voice announcement will give you the time accurate to within one billionth of a second per day.The new service, useful for the synchronization of clocks and communication satellites as well as other applications, is being made available to the military and scientific communities and to the general public. A constant ticking in the background of the recorded phone announcement allows scientific users to synchronize their equipment.

Laser Ranging to the Lunar Reconnaissance Orbiter: improved timing and orbits

NASA Astrophysics Data System (ADS)

Mao, D.; Mcgarry, J.; Sun, X.; Torrence, M. H.; Skillman, D.; Hoffman, E.; Mazarico, E.; Rowlands, D. D.; Golder, J.; Barker, M. K.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

2013-12-01

The Laser ranging (LR) experiment to the Lunar Reconnaissance Orbiter (LRO) has been under operation for more than 4 years, since the launch of the spacecraft in June 2009. Led by NASA's Next Generation Satellite Laser Ranging(NGSLR) station at Greenbelt, Maryland, ten laser ranging stations over the world have been participating in the experiment and have collected over 3,200 hours of ranging data. These range measurements are used to monitor the behavior of the LRO clock and to generate orbital solutions for LRO. To achieve high-quality results in range, ground stations like NGSLR are using H-maser clocks to obtain a stable and continuous time baseline for the orbit solutions. An All-View GPS receiver was included at NGSLR since January 2013 which monitors the H-maser time against the master clock at the United State Naval Observatory (USNO) via the GPS satellites. NGSLR has successfully established nano-second level epoch time accuracy and 10-15 clock stability since then. Time transfer experiments using LRO as a common receiver have been verified in ground testing between NGSLR and MOBLAS7 via a ground terminal with a Lunar Orbiter Laser Altimeter (LOLA)-like receiver at Greenbelt, Maryland. Two hour-long ground tests using a LOLA-like detector and two different ground targets yielded results consistent with each other, and those from the previous 10-minute test completed one year ago. Time transfer tests between NGSLR and MOBLAS7 via LRO are ongoing. More time transfer tests are being planned from NGSLR to McDonald Laser Ranging Station (MLRS) in Texas and later from NGSLR to European satellite laser ranging (SLR) stations. Upon the completion of these time transfer experiments, nanosecond-level epoch time accuracy will be brought to stations besides NGSLR, and such high precision of the ground time can contribute to the LRO precision orbit determination (POD) process. Presently, by using the high-resolution GRAIL gravity models, the LRO orbits determined from LR data alone have a total position error of 10 meters in average, and show the same quality as those generated using conventional radiometric tracking data. In these LR orbital solutions, a bias was adjusted to compensate both the ground and spacecraft clock characteristics. By taking advantage of the knowledge we have gained through LR of the long-term stability of the LRO clock, the spacecraft clock behavior is separated from the ground station clocks and modeled over a 10-month time span in our current POD process. Here we present the results from this new approach, and further improvements in the quality of the orbital reconstruction.

The Weak-Line T Tauri Star V410 Tau

DTIC Science & Technology

2003-01-01

700052 Tashkent, Uzbekistan 7 USRA/USNO Flagstaff Station, PO Box 1149, Flagstaff, AZ 86002-1149, USA 8 Thüringer Landessternwarte, Karl ... Schwarzschild -Observatorium, Sternwarte 5, 07778 Tautenburg, Germany 9 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 10

Two-Way Time Transfer via Geostationary Satellites NRC/NBS, NRC/USNO and NBS/USNO via Hermes and NRC/LPTF (France) via Symphonie

NASA Technical Reports Server (NTRS)

Costain, C.; Boulanger, J. S.; Daams, H.; Hanson, D. W.; Beehler, R. E.; Clements, A. J.; Davis, D. D.; Klepczynski, W. J.; Veenstra, L. B.; Kaiser, J.

1979-01-01

In most of the experiments, 1 pps pulses of the station atomic clocks were exchanged between the partners, and a cubic equation was fitted to the 1000 to 2000 second measurements. The equations were exchanged and substracted to obtain the time difference of the stations. The standard deviation in the fit of the equations varied, depending on conditions, from 1.5 ns to 16 ns. For the last month of the Hermes experiment, a 1 MHz signal was used, giving a standard deviation of 0.18 ns. The comparison of the time scales via satellite and via Loran-C (BIH Circular D) show clearly that some Loran-C links are very good, but that the NBS link varies by 1 micron s. Via the satellite the frequencies of the time scales can be compared with an accuracy of 2 x 10 to the minus 14 power.

VizieR Online Data Catalog: New white dwarf stars in SDSS DR10 (Kepler+, 2015)

NASA Astrophysics Data System (ADS)

Kepler, S. O.; Pelisoli, I.; Koester, D.; Ourique, G.; Kleinman, S. J.; Romero, A. D.; Nitta, A.; Eisenstein, D. J.; Costa, J. E. S.; Kulebi, B.; Jordan, S.; Dufour, P.; Giommi, P.; Rebassa-mansergas, A.

2015-07-01

The targeted white dwarfs were required to be point sources with clean photometry, and to have USNO-B Catalog counterparts (Monet et al.. 2003, Cat. I/284). They were also restricted to regions inside the DR7 imaging footprint and required to have colours within the ranges g<19.2, (u-r)<0.4, -1<(u-g)<0.3, -1<(g-r)<0.5 and to have low Galactic extinction Ar<0.5mag. Additionally, targets that did not have (u-r)<-0.1 and (g-r)<-0.1 were required to have USNO proper motions larger than 2 arcsec per century. Objects satisfying the selection criteria that had not been observed previously by the SDSS were denoted by the WHITEDWARF_NEW target flag, while those with prior SDSS spectra are assigned the WHITEDWARF_SDSS flag. Some of the latter were re-observed with BOSS in order to obtain the extended wavelength coverage that the BOSS spectrograph offers. (1 data file).

Evaluation and Preliminary Results of the New USNO PPS Timing Receiver

DTIC Science & Technology

2000-11-01

timing receiver, one may currently obtain raw pseudorange and carrier-phase data by periodically downloading such data from a flashcard . Several...preliminary experiments have been performed using data collected from the prototype TTR- 12 receivers’ flashcards and geodetic GPS carrier-phase techniques

IRSA

Science.gov Websites

Ipac_logo NASA/IPAC Infrared Science Archive Search for Source Search Radius 10 deg arcmin arcsec Guide for Solar System Observers Search Catalog: WISE 2MASS Spitzer Planck Herschel Gaia COSMOS PTF IRAS MSX AKARI Bolocam USNO DENIS Composite_Catalogs Contributed_Data_Sets INTERNALS Search Catalogs

URAT South Parallax Results

NASA Astrophysics Data System (ADS)

Finch, Charlie T.; Zacharias, Norbert; Jao, Wei-Chun

2018-04-01

We present 916 trigonometric parallaxes and proper motions of newly discovered nearby stars from the United States Naval Observatory Robotic Astrometric Telescope (URAT). Observations were taken at the Cerro Tololo Interamerican Observatory over a 2-year period from 2015 to 2017 October covering the entire sky south of about +25° decl. SPM4 and UCAC4 early epoch catalog data were added to extend the temporal coverage for the parallax and proper motion fit up to 48 years. Using these new URAT parallaxes, optical and near-IR photometry from the AAVSO Photometric All-Sky Survey and Two Micron All-Sky Survey catalogs, we identify possible new nearby dwarfs, young stars, low-metallicity subdwarfs and white dwarfs. Comparison to known trigonometric parallaxes shows a high quality of the URAT-based results confirming the error in parallax of the URAT south parallaxes reported here to be between 2 and 13 mas. We also include additional 729 trigonometric parallaxes from the URAT north 25 pc sample published in Finch & Zacharias here after applying the same criterion as for the southern sample to have a complete URAT 25 pc sample presented in this paper.

LED Street Lighting Solutions: Flagstaff, Arizona as a Case Study

NASA Astrophysics Data System (ADS)

Hall, Jeffrey C.

2018-01-01

Dark-sky protection in Flagstaff, Arizona extends back to 1958, with the first ordinance in the City banning advertising floodlights. The current ordinance, adopted in 1989, is comprehensive and has played a critical role in maintaining the quality of the night sky for astronomy, tourism, public enjoyment, and other purposes. Flagstaff, like many communities around the world, is now working on a transition from legacy bulb-based technology to LED for its outdoor lighting. The City, Lowell Observatory, the U. S. Naval Observatory, and the Flagstaff Dark Skies Coalition have been working intensively for two years to identify an LED-based street lighting solution that will preserve the City's dark skies while meeting municipal needs. We will soon be installing test fixtures for an innovative solution incorporating narrow-band amber LED and modest amounts of low-CCT white LED. In this talk, I will review the types of LEDs available for outdoor lighting and discuss the plans for Flagstaff's street lighting in the LED era, which we hope will be a model for communities worldwide.

A deep proper motion catalog within the Sloan digital sky survey footprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munn, Jeffrey A.; Harris, Hugh C.; Tilleman, Trudy M.

2014-12-01

A new proper motion catalog is presented, combining the Sloan Digital Sky Survey (SDSS) with second epoch observations in the r band within a portion of the SDSS imaging footprint. The new observations were obtained with the 90prime camera on the Steward Observatory Bok 90 inch telescope, and the Array Camera on the U.S. Naval Observatory, Flagstaff Station, 1.3 m telescope. The catalog covers 1098 square degrees to r = 22.0, an additional 1521 square degrees to r = 20.9, plus a further 488 square degrees of lesser quality data. Statistical errors in the proper motions range from 5 masmore » year{sup −1} at the bright end to 15 mas year{sup −1} at the faint end, for a typical epoch difference of six years. Systematic errors are estimated to be roughly 1 mas year{sup −1} for the Array Camera data, and as much as 2–4 mas year{sup −1} for the 90prime data (though typically less). The catalog also includes a second epoch of r band photometry.« less

Geophysical Data Collected off the South Shore of Martha's Vineyard, Massachusetts

USGS Publications Warehouse

Denny, J.F.; Danforth, W.W.; Foster, D.S.; Sherwood, C.R.

2010-01-01

The U.S. Geological Survey Woods Hole Science Center conducted a nearshore geophysical survey offshore of the southern coast of Martha's Vineyard, in the vicinity of the Martha's Vineyard Coastal Observatory in 2007. This mapping program was part of a larger research effort supporting the Office of Naval Research Ripples Directed-Research Initiative studies at Martha's Vineyard Coastal Observatory designed to improve our understanding of coastal sediment-transport processes. The survey was conducted aboard the Megan T. Miller August 9-13, 2007. The study area covers 35 square kilometers from about 0.2 kilometers to 5 kilometers offshore of the south shore of Martha's Vineyard, and ranges in depth from ~6 to 24 meters. The geophysical mapping utilized the following suite of high-resolution instrumentation to map the surficial sediment distribution, bathymetry, and sub-surface geology: a dual-frequency 100/500 kilohertz sidescan-sonar system, 234 kilohertz interferometric sonar, and 500 hertz -12 kilohertz chirp subbottom profiler. These geophysical data will be used to provide initial conditions for wave and circulation modeling within the study area.

Initial Results From the USNO Dispersed Fourier Transform Spectrograph

DTIC Science & Technology

2007-01-25

the full instrument bandpass. 5.2. k Andromedae and Geminorum To test whether the dFTS system can accurately detect RV variations in a stellar...prototype dFTS can measure stellar RVs with sufficient accuracy to find exoplanets. We also observed Andromedae (a three-planet system) and

The challenges and frustrations of a veteran astronomical optician: Robert Lundin, 1880-1962

NASA Astrophysics Data System (ADS)

Briggs, John W.; Osterbrock, Donald E.

1998-12-01

Robert Lundin, apprenticed in nineteenth century optical craftsmanship but employed in twenty century fabrication and engineering, suffered many frustrations during a nonetheless productive career. Son of Carl A.R. Lundin, a senior optician at the famous American firm of Alvan Clark & Sons, Robert grew up building telescopes. As a teenager, he assisted with projects including the 1-m [40-inch] objective for Yerkes Observatory. After his father's death in 1915, he became manager of the Clark Corporation and was responsible for many smaller, successful refractors and reflectors. Lundin also completed major projects, including a highly praised 50.8-cm achromat for Van Vleck Observatory, as well as a successful 33-cm astrograph used at Lowell to discover Pluto. In 1929, a dispute with the owners of the Clark Corporation led to Lundin's resignation and his creation of a new business, "C.A. Robert Lundin and Associates." This short-lived firm built several observatory refractors, including a 26.7 cm for E.W. Rice, the retired chairman of General Electric. But none was entirely successful, and the Great Depression finished off the company. In 1933, Lundin took a job as head of Warner & Swasey's new optical shop, only to experience his greatest disasters. The 2.08-m [82-inch] reflector for McDonald Observatory was delayed for years until astronomers uncovered an error in Lundin's procedure for testing the primary mirror. A 38.1-cm photographic lens for the Naval Observatory was a complete failure. Under pressure to complete a 61-cm Schmidt camera, Lundin seems to have attempted to deceive visiting astronomers. After retirement in the mid 1940s, Lundin moved to Austin, Texas, the home of his daughter, where he died. His difficulties should not obscure his success with many instruments that continue to serve as important research and education tools.

AstroNavigation: Freely-available Online Instruction for Performing a Sight Reduction

NASA Astrophysics Data System (ADS)

Gessner Stewart, Susan; Grundstrom, Erika; Caudel, Dave

2015-08-01

A reliable method of obtaining your geographic location from observations of celestial bodies is globally available. This online learning module, developed through a collaboration between Vanderbilt University and the U.S. Naval Observatory, serves to address the need for freely-available comprehensive instruction in celestial navigation online. Specifically targeted are the steps of preforming a sight reduction to obtain a terrestrial position using this technique. Difficult concepts such as plotting on a navigational chart and the complexities of using navigation publications are facilitated through this online content delivery, rooted in effective course design principles. There is good potential in using celestial navigation as a tool for stimulating interest in astronomy given its resourcefulness and accessibility.

Candidates of World Heritage Sites of Astronomy in Japan

NASA Astrophysics Data System (ADS)

Watanabe, Jun-ichi; Nakagiri, Masao

2015-08-01

Unfortunately there is no heritage site of astronomy until now in Japan. Here we report several candidates based on the importance from the historical point of view.One is the “Nisshinkan” Astronomical Observatory site of the Edo era. Many observatories were established in the Edo era, including "Asakusa observatory" of a Shogunate Government. However, most of them have been disappeared by the urban development. The only one remained until now is the “Nissshinkan” Astronomical Observatory site of which the basement made of stones is preserved. This was made in 1803 mainly for educational purpose at the “Nisshinkan” which was a local school for the Samurai’s children in Aizu area. Although a wooden building of the school was lost by a war, but this observatory mark exists because large basement of a few meters high remained. This site is now designated as a cultural asset by the local government, and can be recognized even at the present time.Another is the Repsold Meridian Transit which was designated as the Important Cultural Property of Japan in 2011. A Repsold meridian transit instrument is a telescope with a diameter of 13.5 cm and a focal length of 212 cm for meridian transit observations. It was manufactured by A. Repsold & Soehne Co. Ltd. in Hamburg, Germany in 1880, and purchased by the Naval Observatory and imported to Japan in 1881, becoming one of the most important telescopes in the dawning era of modern astronomy in Japan. The telescope escaped being damaged in the Great Kanto Earthquake, and continued to be used as a main telescope for time determination, longitude observation, and astrometry of heavenly bodies till the end of the 1950s. We confirmed that this telescope has retained its original form in 2008, and after restoration and repair, the telescope was widely opened for exhibition to the public. In June, 2011 it was designated as one of the important cultural properties of Japan. The related old instruments which brought modern astronomy into Japan are also introduced in this report.

STRUCTURE AND DYNAMICS OF THE 2012 NOVEMBER 13/14 ECLIPSE WHITE-LIGHT CORONA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasachoff, J. M.; Rušin, V.; Saniga, M.

2015-02-20

Continuing our series of observations of coronal motion and dynamics over the solar-activity cycle, we observed from sites in Queensland, Australia, during the 2012 November 13 (UT)/14 (local time) total solar eclipse. The corona took the low-ellipticity shape typical of solar maximum (flattening index ε = 0.01), a change from the composite coronal images we observed and analyzed in this journal and elsewhere for the 2006 and 2008-2010 eclipses. After crossing the northeast Australian coast, the path of totality was over the ocean, so further totality was seen only by shipborne observers. Our results include velocities of a coronal massmore » ejection (CME; during the 36 minutes of passage from the Queensland coast to a ship north of New Zealand, we measured 413 km s{sup –1}) and we analyze its dynamics. We discuss the shapes and positions of several types of coronal features seen on our higher-resolution composite Queensland coronal images, including many helmet streamers, very faint bright and dark loops at the bases of helmet streamers, voids, and radially oriented thin streamers. We compare our eclipse observations with models of the magnetic field, confirming the validity of the predictions, and relate the eclipse phenomenology seen with the near-simultaneous images from NASA's Solar Dynamics Observatory (SDO/AIA), NASA's Extreme Ultraviolet Imager on Solar Terrestrial Relations Observatory, ESA/Royal Observatory of Belgium's Sun Watcher with Active Pixels and Image Processing (SWAP) on PROBA2, and Naval Research Laboratory's Large Angle and Spectrometric Coronagraph Experiment on ESA's Solar and Heliospheric Observatory. For example, the southeastern CME is related to the solar flare whose origin we trace with a SWAP series of images.« less

Performance and Applications of an Ensemble of Atomic Fountains

DTIC Science & Technology

2012-01-01

continuous operation. At some institutions, only one fountain clock contributes to the ensemble at a given time, although two clocks at PTB and three at...at USNO is funded by SPAWAR. REFERENCES [1] A. Bauch, S. Weyers, D. Piester, E. Staliuniene, and W. Yang, “Generation of UTC( PTB ) as a fountain

Angles and Range: Initial Orbital Determination with the Air Force Space Surveillance Telescope (AFSST)

DTIC Science & Technology

2008-09-01

Tycho-2 [12], UCAC-2 [8], USNO-B1.0 [7] supplemented with data from 2MASS [13]. The final intrinsic issue is whether terrestrial parallax...www.ipac.caltech.edu/ 2mass /releases/allsky/ [14] Strand, K. Aa. 1963, “Trigonometric Parallaxes” in Basic Astronomical Data (University of Chicago

The Master Clock Building at USNO Infrastructure

DTIC Science & Technology

2008-12-01

type finish on top of about 3.5 inches of foam insulation. This along with cinder block, fiber glass insulation, and 5/8-inch-X drywall provides a...keep the building on temperature. The outside surface of the building is an “Exterior Finish Insulation Systems” (EFIS). This is made up of a stucco

VizieR Online Data Catalog: Orbits based on SOAR speckle interferometry. II. (Tokovinin, 2017)

NASA Astrophysics Data System (ADS)

Tokovinin, A.

2018-01-01

We present new or updated orbits of 44 binary systems or subsystems. It is based on speckle interferometric measurements made at the 4.1m Southern Astrophysical Research (SOAR) telescope (Tokovinin et al. 2010, Cat. J/AJ/139/743; 2014, Cat. J/AJ/147/123; 2015, Cat. J/AJ/150/50; 2016, Cat. J/AJ/151/153; 2010PASP..122.1483T; Tokovinin 2012, Cat. J/AJ/144/56) combined with archival data collected in the Washington Double Star Catalog (WDS; Mason et al. 2001-2014, Cat. B/wds). It continues previous work on binary orbits resulting from the SOAR speckle program and follows the template of the Paper I (Tokovinin 2016, Cat. J/AJ/152/138), where the motivation is discussed. Briefly, the calculation of binary orbits is part of the astronomical infrastructure, and visual orbital elements are used in many areas. The state of the art is reflected in the Sixth Catalog of Visual Binary Orbits (VB6; Hartkopf et al. 2001AJ....122.3472H; http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6.html). (5 data files).

THE FIRST DISTANCE CONSTRAINT ON THE RENEGADE HIGH-VELOCITY CLOUD COMPLEX WD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peek, J. E. G.; Roman-Duval, Julia; Tumlinson, Jason

2016-09-10

We present medium-resolution, near-ultraviolet Very Large Telescope/FLAMES observations of the star USNO-A0600-15865535. We adapt a standard method of stellar typing to our measurement of the shape of the Balmer ϵ absorption line to demonstrate that USNO-A0600-15865535 is a blue horizontal branch star, residing in the lower stellar halo at a distance of 4.4 kpc from the Sun. We measure the H and K lines of singly ionized calcium and find two isolated velocity components, one originating in the disk, and one associated with the high-velocity cloud complex WD. This detection demonstrated that complex WD is closer than ∼4.4 kpc andmore » is the first distance constraint on the +100 km s{sup −1} Galactic complex of clouds. We find that complex WD is not in corotation with the Galactic disk, which has been assumed for decades. We examine a number of scenarios and find that the most likely scenario is that complex WD was ejected from the solar neighborhood and is only a few kiloparsecs from the Sun.« less

Spectral and photometric studies of the polar USNO-A2.0 0825-18396733

NASA Astrophysics Data System (ADS)

Gabdeev, M. M.; Borisov, N. V.; Shimansky, V. V.; Spiridonova, O. I.

2015-03-01

Results of photometric and spectral studies of the new magnetic cataclysmic variable (polar) USNO-A2.0 0825-18396733 are presented. Photometric data in the B, V, and R c filters show that this object exhibits a red excess of R c - V = 1 m . A red continuum with superposed strong single-peaked Balmer emission lines and HeII λ4686 Å emission, weak lines of neutral helium, and lines of heavy elements are observed in the object's spectra. Doppler maps constructed using the hydrogen and ionized-helium lines indicate that these lines form near the inner Lagrangian point, and that their formation is associated with an accretion stream. The spectra and radial-velocity curves indicate the eclipse of the white dwarf in the system to be partial. Radial-velocity curves derived for emission lines are used to estimate the component masses. The mass of the white dwarf is estimated to be 0.71-0.78 M ⊙, and the mass of the red dwarf to be 0.18-0.20 M ⊙.

The Full-sky Astrometric Mapping Explorer - Astrometry for the New Millennium

NASA Astrophysics Data System (ADS)

Horner, S. D.; Germain, M. E.; Greene, T. P.; Harris, F. H.; Johnson, M. S.; Johnson, K. J.; Monet, D. G.; Murison, M. A.; Phillips, J. D.; Reasenberg, R. D.; Seidelmann, P. K.; Urban, S. E.; Vassar, R. H.

FAME is designed to perform an all-sky, astrometric survey with unprecedented accuracy. It will create a rigid astrometric catalog of ~40,000,000 stars with visual band magnitudes 5 < V < 15. For bright stars, 5 < V < 9, FAME will determine positions and parallaxes accurate to < 50 microarcseconds, with proper motion errors < 50 microarcseconds/year. For fainter stars, 9 < V < 15, FAME will determine positions and parallaxes accurate to < 300 microarcseconds, with proper motion errors < 300 microarcseconds/year. It will also collect photometric data on these 40,000,000 stars in four Sloan DSS colors. The FAME data will provide a rigid, accurate, optical, astrometric grid. The proper motion data, combined with Hipparcos and other data should be ideal for use by the Space Interferometry Mission (SIM) to select its astrometric reference grid stars. FAME will also identify stars with nonlinear proper motions as candidates for further study by SIM, Terrestrial Planet Finder, and future ground based interferometers as possible planetary systems. The fundamental astrometric data provided at relatively low cost by FAME will help optimize the scientific return from these future projects. This is in addition to the considerable direct scientific return from FAME. It will redefine the extragalactic distance scale and provide a large, rich database of information on stellar properties that will enable numerous science investigations into stellar structure and evolution, the dynamics of the Milky Way, and stellar companions including brown dwarfs and giant planets. NASA has selected the Full-sky Astrometric Mapping Explorer (FAME) to be one of five MIDEX missions to be funded for a concept study. This concept study will be submitted to NASA on 18 June, with final selection, scheduled for September, of two of these missions for fli ght in 2003 or 2004. FAME is a joint development e ffort of the U.S. Naval Observatory, the Smithsonian Astrophysical Observatory, the Infrared Processing and Analysis Center, Lockheed Martin Missiles and Space, the Naval Research Laboratory, and Omitron Incorporated.

HUBBLE OBSERVES THE MOONS AND RINGS OF THE PLANET URANUS

NASA Technical Reports Server (NTRS)

2002-01-01

This NASA Hubble Space Telescope image of the planet Uranus reveals the planet's rings, at least five of the inner moons, and bright clouds in the planet's southern hemisphere. Hubble now allows astronomers to revisit the planet at a level of detail not possible since the Voyager 2 spacecraft flew by the planet briefly, nearly a decade ago. Hubble's new view was obtained on August 14, 1994, when Uranus was 1.7 billion miles (2.8 billion kilometers) from Earth. Similar details, as imaged by the Wide Field Planetary Camera 2, were only previously seen by the Voyager 2 spacecraft that flew by Uranus in 1986 (the rings were discovered by stellar occultation experiments in 1977, but not seen directly until Voyager flew to Uranus). Since the flyby, none of these inner satellites has been observed further, and detailed observations of the rings and Uranus' atmosphere have not been possible, because the rings are lost in the planet's glare as seen through ground-based optical telescopes. Each of the inner moons appears as a string of three dots in this picture because it is a composite of three images, taken about six minutes apart. When these images are combined, they show the motion of the moons compared with the sky background. Because the moons move much more rapidly than our own Moon, they change position noticeably over only a few minutes. (These multiple images also help to distinguish the moons from stars and imaging detector artifacts, i.e., cosmic rays and electronic noise). Thanks to Hubble's capabilities, astronomers will now be able to determine the orbits more precisely. With this increase in accuracy, astronomers can better probe the unusual dynamics of Uranus' complicated satellite system. Measuring the moons' brightness in several colors might offer clues to the satellites' origin by providing new information on their mineralogical composition. Similar measurements of the rings should yield new insights into their composition and origin. One of the four gas giant planets of our solar system, Uranus is largely featureless. HST does reveal a high altitude haze which appears as a bright 'cap' above the planet's south pole, along with clouds at southern latitudes (similar structures were observed by Voyager). Unlike Earth, Uranus' south pole points toward the Sun during part of the planet's 84-year orbit. Thanks to its high resolution and ability to make observations over many years, Hubble can follow seasonal changes in Uranus' atmosphere, which should be unusual given the planet's large tilt. Credit: Kenneth Seidelmann, U.S. Naval Observatory, and NASA These observations were conducted by a team led by Dr. Ken Seidelmann of the U.S. Naval Observatory as Principal Investigator. These images have been processed by Professor Douglas Currie and Mr. Dan Dowling in the Department of Physics at the University of Maryland. Other team members are Dr. Ben Zellner at Georgia Southern University, Dr. Dan Pascu and Mr. Jim Rhode at the U.S. Naval Observatory, and Dr. Ed Wells, Mr. Charles Kowal (Computer Science Corporation) and Dr. Alex Storrs of the Space Telescope Science Institute.

STRUCTURE AND DYNAMICS OF THE 2010 JULY 11 ECLIPSE WHITE-LIGHT CORONA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasachoff, J. M.; Rusin, V.; Saniga, M.

The white-light corona (WLC) during the total solar eclipse on 2010 July 11 was observed by several teams in the Moon's shadow stretching across the Pacific Ocean and a number of isolated islands. We present a comparison of the WLC as observed by eclipse teams located on the Tatakoto Atoll in French Polynesia and on Easter Island, 83 minutes later, combined with near-simultaneous space observations. The eclipse was observed at the beginning of the solar cycle, not long after solar minimum. Nevertheless, the solar corona shows a plethora of different features (coronal holes, helmet streamers, polar rays, very faint loopsmore » and radial-oriented thin streamers, a coronal mass ejection, and a puzzling 'curtain-like' object above the north pole). Comparing the observations from the two sites enables us to detect some dynamic phenomena. The eclipse observations are further compared with a hairy-ball model of the magnetic field and near-simultaneous images from the Atmospheric Imaging Assembly on NASA's Solar Dynamics Observatory, the Extreme Ultraviolet Imager on NASA's Solar Terrestrial Relations Observatory, the Sun Watcher, using Active Pixel System Detector and Image Processing on ESA's PRoject for Onboard Autonomy, and the Naval Research Laboratory's Large Angle and Spectrometric Coronagraph on ESA's Solar and Heliospheric Observatory. The Ludendorff flattening coefficient is 0.156, matching the expected ellipticity of coronal isophotes at 2 Rs{sub un}, for this rising phase of the solar-activity cycle.« less

Pluto-Charon: a test of the astrometric approach for finding asteroid satellites

NASA Astrophysics Data System (ADS)

Kikwaya, J.-B.; Thuillot, W.; Berthier, J.

2003-05-01

The astrometric method to find asteroid satellites is based on the search for the reflex effect on the primary object due to the orbital motion of a possible satellite (Monet & Monet 1998, Kikwaya et al. 2002). As reported by Kikwaya et al. (2003), the astrometric signature of a satellite of 146 Lucina may reach several mas. Spectral analysis might then detect the signal under good conditions of signal/noise ratio, with high quality astrometric measurements and large coverage by different sites of observation. However, the astrometric method cannot be applied to any binary system of asteroids. It depends strongly on the mass ratio of the two bodies and the distance between them (Kikwaya et al. 2002). Pluto-Charon provides a good test of this method. Previous works based on direct imaging of Charon show that its period is 6.357 days and the mass ratio is 0.122 (Wasserman et al. 2000), putting this system into the range that can be observed by our method. Using archived photographic observations (1914-1995) and CCD observations from US Naval Observatory, Flagstaff station (1995-1998), Bordeaux observatory (1996-1997) and Mc Donald Observatory (1997), we are analyzing the position of Pluto to see if its wobble effect due to Charon (amplitude around 95 mas) can be detected and if the orbital period of Charon can be recovered through a spectral analysis. If successful, this will reinforce the ability of our astrometric method to find asteroid satellites.

51 Eridani and GJ 3305: A 10-15 Myr old Binary Star System at 30 Parsecs

NASA Astrophysics Data System (ADS)

Feigelson, E. D.; Lawson, W. A.; Stark, M.; Townsley, L.; Garmire, G. P.

2006-03-01

Following the suggestion of Zuckerman and coworkers, we consider the evidence that 51 Eri (spectral type F0) and GJ 3305 (M0), historically classified as unrelated main-sequence stars in the solar neighborhood, are instead a wide physical binary system and members of the young β Pic moving group (BPMG). The BPMG is the nearest (d<~50 pc) of several groups of young stars with ages around 10 Myr that are kinematically convergent with the Oph-Sco-Cen association (OSCA), the nearest OB star association. Combining South African Astronomical Observatory optical photometry, Hobby-Eberly Telescope high-resolution spectroscopy, Chandra X-Ray Observatory data, and Second US Naval Observatory CCD Astrograph Catalog kinematics, we confirm with high confidence that the system is indeed extremely young. GJ 3305 itself exhibits very strong magnetic activity but has rapidly depleted most of its lithium. The 51 Eri/GJ 3305 system is the westernmost known member of the OSCA, lying 110 pc from the main subgroups. The system is similar to the BPMG wide binary HD 172555/CD -64 1208 and the HD 104237 quintet, suggesting that dynamically fragile multiple systems can survive the turbulent environments of their natal giant molecular cloud complexes, while still having high dispersion velocities imparted. Nearby young systems such as these are excellent targets for evolved circumstellar disk and planetary studies, having stellar ages comparable to that of the late phases of planet formation.

Design and operation of a Loran-C time reference station

NASA Technical Reports Server (NTRS)

Putkovich, K.

1974-01-01

Some of the practical questions that arise when one decides to use Loran-C in a time reference system are explored. An extensive effort is made to provide basic, practical information on establishing and operating a reference station. Four areas were covered: (1) the design, configuration and operational concepts which should be considered prior to establishing and operating a reference station using Loran-C, (2) the options and tradeoffs available regarding capabilities, cost, size, versatility, ease of operation, etc., that are available to the designer, (3) what measurements are made, how they are made and what they mean, and (4) the experience the U.S. Naval Observatory Time Service Division has had in the design and operation of such stations.

Evaluation of models proposed for the 1991 revision of the International Geomagnetic Reference Field

USGS Publications Warehouse

Peddie, N.W.

1992-01-01

The 1991 revision of the International Geomagnetic Reference Field (IGRF) comprises a definitive main-field model for 1985.0, a main-field model for 1990.0, and a forecast secular-variation model for the period 1990-1995. The five 1985.0 main-field models and five 1990.0 main-field models that were proposed have been evaluated by comparing them with one another, with magnetic observatory data, and with Project MAGNET aerial survey data. The comparisons indicate that the main-field models proposed by IZMIRAN, and the secular-variation model proposed jointly by the British Geological Survey and the US Naval Oceanographic Office, should be assigned relatively lower weight in the derivation of the new IGRF models. -Author

Progress on the Low Frequency All Sky Monitor

NASA Astrophysics Data System (ADS)

Ford, Anthony; Jenet, F.; Craig, J.; Creighton, T. D.; Dartez, L. P.; Hicks, B.; Hinojosa, J.; Jaramillo, R.; Kassim, N. E.; Lunsford, G.; Miller, R. B.; Murray, J.; Ray, P. S.; Rivera, J.; Taylor, G. B.

2013-01-01

The Low Frequency All Sky Monitor is a system of geographically separated radio arrays dedicated to the study of radio transients. LoFASM consists of four stations, each comprised of 12 cross-dipole antennas designed to operate between 5-88MHz. The antennas and front end electronics for LoFASM were designed by the Naval Research Laboratory for the Long Wavelength Array project. Over the last year, undergraduate students from the University of Texas at Brownsville’s Center for Advanced Radio Astronomy have been establishing these stations around the continental US, consisting of sites located in Port Mansfield, Texas, the LWA North Arm site of the LWA1 Radio Observatory in New Mexico, adjacent to the North Arm of the Very Large Array, the Green Bank Radio Observatory, West Virginia, and NASA’s Goldstone tracking complex in California. In combination with the establishment of these sites was the development of the analog hardware, which consists of commercial off-the-shelf RF splitter/combiners and a custom amplifier and filter chain designed by colleagues at the University of New Mexico. This poster will expound on progress in site installation and development of the analog signal chain.

Geodesy/Astrometry with the VLBA

NASA Astrophysics Data System (ADS)

Gordon, David

2000-05-01

The RDV experiments are a joint effort between VLBI scientists at NASA Goddard Space Flight Center, the U.S. Naval Observatory, and the National Radio Astronomy Observatory (an NSF facility operated by Associated Universities, Inc.). Six RDV geodesy/astrometry experiments are conducted yearly, using the 10 VLBA antennas and up to 10 Mark 4 antennas. Correlation is done on the VLBA correlator, a station-based, geocenter referenced correlator, similar to the new Mark 4 correlators. VLBA correlator output is in the form of cross-spectra phase and amplitude visibility data, which must be further processed using the NRAO AIPS software package to obtain geodetic observables. Most of the geodetic processing has been done at GSFC, using steps developed by NRAO and GSFC staff. These steps are given in a geodesy processing guide, available on-line in AIPS by typing "EXPLAIN ASTROMET". The first 17 RDV experiments, spanning 2.6 years, have been processed and, except for one problem (known as the southern source problem), the results are fairly good. The baseline repeatabilities are generally as good as, or better than, an equivalent span of Mark3/4 data, and many of the experiments can be phase connected between most of the VLBA antennas.

The Solar Neighborhood. XXXIX. Parallax Results from the CTIOPI and NOFS Programs: 50 New Members of the 25 parsec White Dwarf Sample

NASA Astrophysics Data System (ADS)

Subasavage, John P.; Jao, Wei-Chun; Henry, Todd J.; Harris, Hugh C.; Dahn, Conard C.; Bergeron, P.; Dufour, P.; Dunlap, Bart H.; Barlow, Brad N.; Ianna, Philip A.; Lépine, Sébastien; Margheim, Steven J.

2017-07-01

We present 114 trigonometric parallaxes for 107 nearby white dwarf (WD) systems from both the Cerro Tololo Inter-American Observatory Parallax Investigation (CTIOPI) and the U. S. Naval Observatory Flagstaff Station (NOFS) parallax programs. Of these, 76 parallaxes for 69 systems were measured by the CTIOPI program and 38 parallaxes for as many systems were measured by the NOFS program. A total of 50 systems are confirmed to be within the 25-pc horizon of interest. Coupled with a spectroscopic confirmation of a common proper-motion companion to a Hipparcos star within 25 pc as well as confirmation parallax determinations for two WD systems included in the recently released Tycho Gaia Astrometric Solution catalog, we add 53 new systems to the 25-pc WD sample—a 42% increase. Our sample presented here includes four strong candidate halo systems, a new metal-rich DAZ WD, a confirmation of a recently discovered nearby short-period (P = 2.85 hr) double degenerate, a WD with a new astrometric perturbation (long period, unconstrained with our data), and a new triple system where the WD companion main-sequence star has an astrometric perturbation (P ˜ 1.6 year).

Catalog based two-color, relative photometry of NEOs at McDonald Observatory

NASA Astrophysics Data System (ADS)

Barker, E. S.; Györgyey Ries, J.; Shelus, P. J.; Ricklefs, R. L.

2001-11-01

The McDonald Observatory astrometry group has been involved in Solar System positional observations since the early 1970's. Since 1995, it has evolved to a CCD-based, almost totally automated, astrometry package. We are focusing our observational program on Near Earth Objects (NEOs) as part of NASA's mission to discover and catalogue 90 percent of NEOs with diameters larger than 1 km by 2008. We carry out confirmation observations of newly discovered objects and contribute to orbit improvements of under-observed objects. Understanding the overall hazard that these objects pose to Earth requires their dynamical and physical characterization. We recently adopted the USNO-A2.0 catalogue to improve our astrometric results. The catalog, however, also provides stellar magnitudes in the standard Johnson R and B photometric bands. After completing the night’s observing program, we now regularly provide the IAU with R magnitudes in addition to astrometric positions. Our limiting magnitude in R is near 22 in a 15 minute exposure over a 46 arcmin field on the 0.8m prime focus camera. Typically, we are scheduled for 4 nights each lunation, but our semi-automated, IRAF/ICE based program can be used by other 0.8m users. We are testing procedures that will include B and V exposures as part of our standard confirmation triplet. We have confirmed that switching filters between exposures on standard fields does not compromise the astrometric accurary. Thus, we should be able to provide two color, sequential, relative photometry of any newly discovered asteroid, as part of the confirmation process. The time interval between exposures is less than 20 minutes, short compared to most asteroid rotation times. Consequently, a meaningful color index can be obtained in parallel with the astrometric positions. Although B-R is not the usual color index used in asteroid classification studies, we are testing whether we can use it as a quick diagnostic tool to roughly classify newly discovered NEOs as by product of our astrometric observing sequence. Preliminary results will be presented at the meeting. This research is funded by NASA's NEO Observation Program grants NAG5-6863 and NAG5-10183.

Twentieth-century astronomical heritage: the case of the Brazilian National Observatory

NASA Astrophysics Data System (ADS)

Barboza, Christina Helena

2015-08-01

The National Observatory of Brazil was created in 1827. It was initially focused on the practical teaching of Astronomy to the students of military and naval academies. Since the mid-nineteenth century to the early twentieth century it was installed over the ruins of a Jesuit church located in the center of Rio de Janeiro, capital of the Brazilian Empire.Due to the constant complaints of its successive directors, the search for a new site to house the Observatory began in 1911. The new headquarters of the institution were located on the hill of São Januário, a little further but still around the city center of Rio de Janeiro. Its inauguration took place in 1921.The main building of the new Observatory was based on one of the Brazilian pavilions of the Turin Exhibition of 1911, and its architecture can be characterized as eclectic. The pavilions intended to house the many telescopes were scattered in a large wooded area. Since 1985 all these facilities are protected by the Federal government, as a consequence of the same initiative that gave birth to the Museum of Astronomy and Related Sciences, which has the custody also of the Observatory’s former instruments, furniture, and documents.Although built in the early twentieth century the National Observatory new facilities reveal astronomical practices typical of the previous century. One of its most important activities was the determination of the legal time, a task that justifies its location in the urban environment. It was also responsible for the organization of expeditions destined to determine the geographical positions of railroads and the borders of Brazil. For this reason, the Museum of Astronomy has currently more than 3,000 portable instruments. Moreover, these instruments belong to the domain of Astronomy, but also to Geodesy, Meteorology, Electricity. Due to the creation of the Museum of Astronomy, this rich collection is now open to public visitation, and has become the object of scholarly researches in the domain of many disciplines, and mainly in the History of Science.

Sunspot prediction using neural networks

NASA Technical Reports Server (NTRS)

Villarreal, James; Baffes, Paul

1990-01-01

The earliest systematic observance of sunspot activity is known to have been discovered by the Chinese in 1382 during the Ming Dynasty (1368 to 1644) when spots on the sun were noticed by looking at the sun through thick, forest fire smoke. Not until after the 18th century did sunspot levels become more than a source of wonderment and curiosity. Since 1834 reliable sunspot data has been collected by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Naval Observatory. Recently, considerable effort has been placed upon the study of the effects of sunspots on the ecosystem and the space environment. The efforts of the Artificial Intelligence Section of the Mission Planning and Analysis Division of the Johnson Space Center involving the prediction of sunspot activity using neural network technologies are described.

New infrastructure at Alboran island (Western Mediterranean): a submarine and on-land Geophysical Observatory

NASA Astrophysics Data System (ADS)

Pazos, Antonio; Martín Davila, José; Buforn, Elisa; Jesús García Fernández, Maria; Bullón, Mercedes; Gárate, Jorge

2010-05-01

The Eurasian-African plate boundary crosses the called "Ibero-Maghrebian" region from San Vicente Cape (SW Portugal) to Tunisia including the South of Iberia, Alboran Sea, and northern of Morocco and Algeria. The low convergence rate at this plate boundary produces a continuous moderate seismic activity of low magnitude and shallow depth, where the occurrence of large earthquakes is separated by long time intervals. In this region, there are also intermediate and very deep earthquakes. Since more than hundred years ago San Fernando Naval Observatory (ROA), in collaboration with other Institutes, has deployed different geophysical and geodetic equipment in the Southern Spain - North-western Africa area in order to study this broad deformation. Currently a Broad Band seismic net (Western Mediterranean, WM net), a permanent geodetic GPS net and a Geomagnetic Observatory have been installed by ROA in this area. To complement the available data, since past October a permanent marine-on land geophysical observatory is being installed by ROA in Alboran Island and surrounding marine zones. Till now the following facilities has been installed: • Submarine: 2 km submarine fibre optics cable (power and data transmission); Broad Band Seismometer (CMG-3T, buried); Accelerometer (Guralp 3 channels), buried); Differential Pressure Gauge (DPG); Thermometer. • On land: Permanent geodetic GPS station; Automatic meteorological station; Data acquisition system for submarine equipment; Satellite Data Transmission system. Data are already being transmitted in real time to ROA headquarters via satellite Intranet. The marine part, currently installed in a 50 m depth platform, has been designed to be enlarged by extending the cable to greater depths and/or installing additional submarine equipment, such a way in short an ADCP profiler will be installed. In this work we aim to show the present status, scientific possibilities and the next future plans of this submarine-on land installation.

New Steering Strategies for the USNO Master Clocks

DTIC Science & Technology

1999-12-01

1992. P. Koppang and R. Leland , “Linear quadratic stochastic control of atomic hydrogen masers,” IEEE Trans. Ultrason., Ferroelect., Freq. Contr...vol. 46, pp. 517-522, May 1999. P. Koppang and R. Leland , “Steering of frequency standards by the use of linear quadratic gaussian control theory...3lst Annual Precise Time and Time Interval (PTTI) Meeting NEWSTEERINGSTRATEGIESFOR THEUSNOMASTERCLOCKS Paul A. Koppang Datum, Inc. Beverly, MA

The discovery of DLT17aw/AT2017drh with PROMPT

NASA Astrophysics Data System (ADS)

Sand, D.; Wyatt, S.; Valenti, S.; Bostroem, K. A.; Tartaglia, L.; Reichart, D. E.; Haislip, J. B.; Kouprianov, V.

2017-05-01

We report the discovery of DLT17aw/AT2017drh. The object was discovered on 2017-05-03.36 UT at R 17.9 mag, during the ongoing D20.5) on 2017-04-29.36 UT. All images were taken in a 'Clear' filter which was calibrated to an approximate R-band magnitude using the USNO-B1 catalog.

The Accuracy of Two-Way Satellite Time Transfer Calibrations

DTIC Science & Technology

2005-01-01

20392, USA Abstract Results from successive calibrations of Two-Way Satellite Time and Frequency Transfer ( TWSTFT ) operational equipment at...USNO and five remote stations using portable TWSTFT equipment are analyzed for internal and external errors, finding an average random error of ±0.35...most accurate means of operational long-distance time transfer are Two-Way Satellite Time and Frequency Transfer ( TWSTFT ) and carrier-phase GPS

In situ measurement of geoacoustic sediment properties: An example from the ONR Mine Burial Program, Martha's Vineyard Coastal Observatory

NASA Astrophysics Data System (ADS)

Kraft, Barbara J.; Mayer, Larry A.; Simpkin, Peter G.; Goff, John A.

2003-04-01

In support of the Office of Naval Research's Mine Burial Program (MBP), in situ acoustic and resistivity measurements were obtained using ISSAP, a device developed and built by the Center for Coastal and Ocean Mapping. One of the field areas selected for the MBP experiments is the WHOI coastal observatory based off Martha's Vineyard. This area is an active natural laboratory that will provide an ideal environment for testing and observing mine migration and burial patterns due to temporal seabed processes. Seawater and surficial sediment measurements of compressional wave sound speed, attenuation, and resistivity were obtained at 87 stations. The ISSAP instrument used four transducer probes arranged in a square pattern giving acoustic path lengths of 30 and 20 cm with a maximum insertion depth of 15 cm. Transducers operated at a frequency of 65 kHz. The received acoustic signal was sampled at a frequency of 5 MHz. A measurement cycle was completed by transmitting 10 pulses on each of the five paths and repeating three times for a total 150 measurements. Resistivity measurements were obtained from two probes mounted on ISSAP following completion of the acoustic measurements. [Research supported by ONR Grant Nos. N00014-00-1-0821 and N00014-02-1-0138.

Laboratory studies in ultraviolet solar physics

NASA Technical Reports Server (NTRS)

Parkinson, W. H.; Kohl, J. L.; Gardner, L. D.; Raymond, J. C.; Smith, P. L.

1991-01-01

The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided.

The Solar Neighborhood. XXXIX. Parallax Results from the CTIOPI and NOFS Programs: 50 New Members of the 25 parsec White Dwarf Sample

DOE Office of Scientific and Technical Information (OSTI.GOV)

Subasavage, John P.; Harris, Hugh C.; Dahn, Conard C.

We present 114 trigonometric parallaxes for 107 nearby white dwarf (WD) systems from both the Cerro Tololo Inter-American Observatory Parallax Investigation (CTIOPI) and the U. S. Naval Observatory Flagstaff Station (NOFS) parallax programs. Of these, 76 parallaxes for 69 systems were measured by the CTIOPI program and 38 parallaxes for as many systems were measured by the NOFS program. A total of 50 systems are confirmed to be within the 25-pc horizon of interest. Coupled with a spectroscopic confirmation of a common proper-motion companion to a Hipparcos star within 25 pc as well as confirmation parallax determinations for two WD systems included inmore » the recently released Tycho Gaia Astrometric Solution catalog, we add 53 new systems to the 25-pc WD sample—a 42% increase. Our sample presented here includes four strong candidate halo systems, a new metal-rich DAZ WD, a confirmation of a recently discovered nearby short-period ( P  = 2.85 hr) double degenerate, a WD with a new astrometric perturbation (long period, unconstrained with our data), and a new triple system where the WD companion main-sequence star has an astrometric perturbation ( P  ∼ 1.6 year).« less

BY POPULAR DEMAND: HUBBLE OBSERVES THE HORSEHEAD NEBULA

NASA Technical Reports Server (NTRS)

2002-01-01

Rising from a sea of dust and gas like a giant seahorse, the Horsehead nebula is one of the most photographed objects in the sky. NASA's Hubble Space Telescope took a close-up look at this heavenly icon, revealing the cloud's intricate structure. This detailed view of the horse's head is being released to celebrate the orbiting observatory's eleventh anniversary. Produced by the Hubble Heritage Project, this picture is a testament to the Horsehead's popularity. Internet voters selected this object for the orbiting telescope to view. The Horsehead, also known as Barnard 33, is a cold, dark cloud of gas and dust, silhouetted against the bright nebula, IC 434. The bright area at the top left edge is a young star still embedded in its nursery of gas and dust. But radiation from this hot star is eroding the stellar nursery. The top of the nebula also is being sculpted by radiation from a massive star located out of Hubble's field of view. Only by chance does the nebula roughly resemble the head of a horse. Its unusual shape was first discovered on a photographic plate in the late 1800s. Located in the constellation Orion, the Horsehead is a cousin of the famous pillars of dust and gas known as the Eagle nebula. Both tower-like nebulas are cocoons of young stars. The Horsehead nebula lies just south of the bright star Zeta Orionis, which is easily visible to the unaided eye as the left-hand star in the line of three that form Orion's Belt. Amateur astronomers often use the Horsehead as a test of their observing skills; it is known as one of the more difficult objects to see visually in an amateur-sized telescope. The magnificent extent of the Horsehead is best appreciated in a new wide-field image of the nebula being released today by the National Optical Astronomy Observatory, taken by Travis Rector with the National Science Foundation's 0.9 meter telescope at Kitt Peak National Observatory near Tucson, AZ. This popular celestial target was the clear winner among more than 5,000 Internet voters, who were asked last year to select an astronomical target for the Hubble telescope to observe. The voters included students, teachers, and professional and amateur astronomers. This 11th anniversary release image was composed by the Hubble Heritage Team, which superimposed Hubble data onto ground-based data (limited to small triangular regions around the outer edge of the image). Ground-based image courtesy of Nigel A. Sharp (NOAO/AURA/NSF) taken at the 0.9-meter telescope on Kitt Peak. Image Credit: NASA, NOAO, ESA and The Hubble Heritage Team (STScI/AURA) Acknowledgment: K. Noll (Hubble Heritage PI/STScI), C. Luginbuhl (USNO), F. Hamilton (Hubble Heritage/STScI)

USNO Master Clock Design Enhancements

DTIC Science & Technology

2007-01-01

25-27 January 1999, San Diego, California, USA (ION, Alexandria, Virginia), pp. 871-880. [3] R. Brown and P. Hwang , 1992, Introduction to Random...to the system include the use of a Kalman filter for phase and frequency estimates, decreasing the time interval between steers, and the redesign of...present operational system utilizes the dynamic mean as described in the previous section, but uses a Kalman filter to estimate the phase and frequency

Accuracy and Precision of USNO GPS Carrier-Phase Time Transfer

DTIC Science & Technology

2010-01-01

values. Comparison measures used include estimates obtained from two-way satellite time/frequency transfer ( TWSTFT ), and GPS-based estimates obtained...the IGS are used as a benchmark in the computation. Frequency values have a few times 10 -15 fractional frequency uncertainty. TWSTFT values confirm...obtained from two-way satellite time/frequency transfer ( TWSTFT ), BIPM Circular T, and the International GNSS Service (IGS). At present, it is known that

VizieR Online Data Catalog: Catalogue enriched with R CrB stars (Tisserand, 2012)

NASA Astrophysics Data System (ADS)

Tisserand, P.

2012-01-01

For each object, the equatorial and Galactic coordinates are given, as well as all four WISE (Wright et al., 2010AJ....140.1868W, Cat. II/307), three 2MASS (Skrutskie et al., 2006, Cat. VII/233), three DENIS (Epchtein et al., 1994Ap&SS.217....3E, Cat. B/denis) magnitudes, and their related 1-sigma errors. The five USNO-B1 magnitudes (Monet et al., 2003, Cat. I/284) are also listed, but not the individual measurement error since they were not delivered in the original catalogue. If one magnitude was not available, its value was replaced by the number -99. Also, if more than one epoch were available in the DENIS or USNO-B1 catalogues for one particular object, only the epoch related to the brightest magnitudes were kept. The last column of the catalogue gives the SIMBAD classification, as of July 2011, found using a 5 arcsec matching radius. An underscore character was given to the objects that had no classification in SIMBAD. WISE data acquisition and reduction are discussed in Wright et al. (2010AJ....140.1868W) and in the Explanatory Supplement to the WISE Preliminary Data Release Products. There are four WISE bands, with central wavelengths at 3.4, 4.6, 12, and 22um. (2 data files).

UCAC1: New Proper Motions for 27 Million Stars on the Southern Hemisphere

NASA Astrophysics Data System (ADS)

Zacharias, N.; Monet, S. Urban D. G.; Platais, I.; Wycoff, G. L.; Zacharias, M. I.; Rafferty, T. J.

The big impact of UCAC on galactic kinematics and dynamics studies will be outlined. The USNO CCD Astrograph (UCA) started an astrometric sky survey in February 1998 at Cerro Tololo, Chile. By January 2000 about 90% of the Southern Hemisphere has been observed and full sky coverage is expected by early 2003. In addition, calibration fields around extragalactic reference frame sources and selected open clusters are observed frequently. The UCAC project is a huge dedicated astrometric survey similar to the AGK2 and AGK3 projects but vastly exceeding those with respect to higher accuracy, limiting magnitude (16th) and full sky coverage. A first catalog (UCAC1) is being published in early 2000 for 27 million stars. Stars in the range of 9 to 14th magnitude have a positional precision of 20 mas. The UCAC1 will utilize positions from the USNO A2.0 catalog for determining proper motions, which are expected to be about 8 mas/yr for this initial release. Higher precision proper motions, expected to be in the 3 to 4 mas/yr range, will be derived utilizing a variety of early epoch data, including re-measuring of the Southern Proper Motion (SPM) survey first epoch plates.

Obituary: Alan D. Fiala (1942-2010)

NASA Astrophysics Data System (ADS)

Kaplan, George

2011-12-01

Dr. Alan Dale Fiala, astronomer and expert on solar eclipses, died on May 26, 2010 in Arlington, Virginia, of respiratory failure after a brief illness. He was 67. Fiala had been a staff astronomer at the U.S. Naval Observatory in Washington, D.C., for his entire professional career, where he rose from a position as a summer intern to become the Chief of the Nautical Almanac Office, responsible for annual publications for astronomy and navigation that are used the world over. He retired from the observatory in 2000. Although a childhood case of polio affected his mobility for the rest of his life, he seldom let his physical constraints limit his activities, which were many and varied. Alan Fiala was born in Beatrice, Nebraska on November 9, 1942, the middle son of Emil A. ("John") and Lora Marie Fiala. Fiala's father was a postal clerk and Civil Service examiner. Fiala expressed interest in astronomy at a very young age. He contracted polio when he was 9. He graduated from Beatrice High School in 1960 with a straight-A average and went on to study at Carleton College. He received his B.A. summa cum laude after three years, in 1963, with a major in astronomy and minors in physics and mathematics. He was elected to Phi Beta Kappa, Sigma Xi, and Pi Mu Epsilon (mathematics). In 1962, Alan Fiala obtained a job as a summer intern at the Naval Observatory in Washington, working in the Nautical Almanac Office (NAO). He entered the graduate program at Yale University and continued to work summers at the observatory. He received his Ph.D. in 1968, under Gerald Clemence. His dissertation was titled "Determination of the Mass of Jupiter from a Study of the Motion of 57 Mnemosyne." After receiving his doctorate, Fiala became a permanent member of the Naval Observatory staff. Computers were just being introduced there and he participated in the automation of many procedures used to prepare the annual publications of the Nautical Almanac Office. One of his first assignments was to prepare a visual identification chart of the navigational stars to be used for backup navigation on Apollo 8 and several subsequent space missions. In 1973, Alan Fiala was assigned to take over and modernize the prediction of solar and lunar eclipses. He developed software for calculating eclipse phenomena and generating eclipse maps that is still the basis of the computations at the observatory almost four decades later. As one of the world's experts on eclipse calculations, he was the lead author of the chapter on eclipse calculations in the 1992 Explanatory Supplement to the Astronomical Almanac, and was also the co-author of Canon of Lunar Eclipses 1500 B.C-A.D. 3000 with Bao-Lin Liu, the foremost Chinese expert. In 1979, Alan Fiala began a collaborative effort with two other colleagues, supported by NSF and NASA, to observe solar eclipses in order to detect possible long-term variations in the solar diameter. Fiala pioneered the use of portable video cameras to record the disappearance and reappearance of the Sun from behind the Moon's limb during an eclipse, as viewed from the edges of the central eclipse paths. He was the leader or co-organizer of expeditions to ten solar eclipses around the world and was the co-author of several articles on this project. In 1996, Alan Fiala was appointed Chief of the Nautical Almanac Office. The office, which dates from 1849, is responsible for four annual publications that set the international standard for accuracy for positional astronomy and celestial navigation. Fiala made great progress in modernizing and standardizing the production process for the publications. He also began revision of the scientific basis of the books while adding complementary information on the Internet. Fiala was Chief of NAO during its sesquicentennial and, with Steven J. Dick, co-edited the Proceedings of the Nautical Almanac Office Sesquicentennial Symposium. Alan Fiala received numerous awards during his career at the Observatory, including the Captain James Melville Gilliss Award for service. Minor planet 3695 Fiala was named in his honor on the occasion of his retirement in 2000. Alan Fiala was elected to the International Astronomical Union in 1976. He was also a member of the American Astronomical Society, Institute of Navigation, and several other professional societies. He served as the chair of the AAS Division on Dynamical Astronomy during its 25th year. Alan Fiala had many interests outside of astronomy, including sports car racing. He started as a member of a racing team and continued as a volunteer official in technical inspection for the Sports Car Club of America. He was generous with his time, serving as a leader of citizens groups in Northern Virginia and a national organization for people with post-polio syndrome. Other interests included genealogy, gardening, photography, cooking, travel, languages, literature, and the arts. He was also a master beekeeper. Fiala is survived by his two brothers, John and Kent. He was buried in Odell, Nebraska, not far from his childhood home. Fiala will be remembered fondly by his many friends and colleagues, who will miss his good humor and his meticulous approach to any subject he wished to master. Fiala's life was an inspiration to many, and he left behind a valuable legacy of work not just for astronomy, but also for the many organizations to which he donated his time.

A comparison and evaluation of satellite derived positions of tracking stations

NASA Technical Reports Server (NTRS)

Vincent, S. F.; Strange, W. E.; Marsh, J. G.

1971-01-01

A comparison is presented of sets of satellite tracking station coordinate values published in the past few years by a number of investigators, i.e. Goddard Space Flight Center, Smithsonian Astrophysical Observatory, Ohio State University, The Naval Weapons Laboratory, Air Force Cambridge Research Laboratories, and Wallops Island. The comparisons have been made in terms of latitude, longitude and height. The results of the various solutions have been compared directly and also with external standards such as local survey data and gravimetrically derived geoid heights. After taking into account systematic rotations, latitude and longitude agreement on a global basis is generally 15 meters or better, on the North American Datum agreement is generally better than 10 meters. Allowing for scale differences (of the order of 2 ppm) radial agreement is generally of the order of 10 meters.

Status of the test phase of K-3 VLBi system developed in RRL

NASA Astrophysics Data System (ADS)

Saburi, Y.; Yoshimura, K.; Kawajiri, N.; Kawano, N.; Takahashi, F.

An account is given of the last phase of a five-year plan to develop the K-3 system - a high precision VLBI system for applications in a wide variety of fields, such as geodesy, astrometry, and radio astronomy. At the end of 1983, the hardware and software of the K-3 system, were almost completed, and tests were undertaken to demonstrate compatibility with the Mark III system. Topics covered include: Characteristics of the 26-m antenna receiving system, the first U.S.-Japan test observations, and experiments to be conducted for the period up through 1989 at least. Precise time comparison experiments between atomic clocks at the Radio Research Laboratories and the U.S. Naval Observatory were to begin in 1985 and produce data at least once a month for several years.

Two Active Nuclei in 3C 294

NASA Astrophysics Data System (ADS)

Stockton, Alan; Canalizo, Gabriela; Nelan, E. P.; Ridgway, Susan E.

2004-01-01

The z=1.786 radio galaxy 3C 294 lies < 10" from a 12 mag star and has been the target of at least three previous investigations using adaptive optics (AO) imaging. A major problem in interpreting these results is the uncertainty in the precise alignment of the radio structure with the H- or K-band AO imaging. Here we report observations of the position of the AO guide star with the Hubble Space Telescope Fine Guidance Sensor, which, together with positions from the second United States Naval Observatory's CCD Astrograph Catalog (UCAC2), allow us to register the infrared and radio frames to an accuracy of better than 0.1". The result is that the nuclear compact radio source is not coincident with the brightest discrete object in the AO image, an essentially unresolved source on the eastern side of the light distribution, as Quirrenbach and coworkers had suggested. Instead, the radio source is centered about 0.9" to the west of this object, on one of the two apparently real peaks in a region of diffuse emission. Nevertheless, the conclusion of Quirrenbach and coworkers that 3C 294 involves an ongoing merger appears to be correct: analysis of a recent deep Chandra image of 3C 294 obtained from the archive shows that the nucleus comprises two X-ray sources, which are coincident with the radio nucleus and the eastern stellar object. The X-ray/optical flux ratio of the latter makes it extremely unlikely that it is a foreground Galactic star. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. These observations are associated with proposal 08315. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Some of the data were also obtained from the Chandra Data Archive, part of the Chandra X-Ray Observatory Science Center, which is operated for NASA by the Smithsonian Astrophysical Observatory.

Young stars in ɛ Chamaleontis and their disks: disk evolution in sparse associations

NASA Astrophysics Data System (ADS)

Fang, M.; van Boekel, R.; Bouwman, J.; Henning, Th.; Lawson, W. A.; Sicilia-Aguilar, A.

2013-01-01

Context. The nearby young stellar association ɛ Cha has an estimated age of 3-5 Myr, making it an ideal laboratory to study the disk dissipation process and provide empirical constraints on the timescale of planet formation. Aims: We wish to complement existing optical and near-infrared data of the ɛ Cha association, which provide the stellar properties of its members, with mid-infrared data that probe the presence, geometry, and mineralogical composition of protoplanetary disks around individual stars. Methods: We combine the available literature data with our Spitzer/IRS spectroscopy and VLT/VISIR imaging data. We use proper motions to refine the membership of ɛ Cha. Masses and ages of individual stars are estimated by fitting model atmospheres to the optical and near-infrared photometry, followed by placement in the Hertzsprung-Russell diagram. The Spitzer/IRS spectra are analyzed using the two-layer temperature distribution spectral decomposition method. Results: Two stars previously identified as members, CXOU J120152.8 and 2MASS J12074597, have proper motions that are very different from those of the other stars. But other observations suggest that the two stars are still young and thus might still be related to ɛ Cha. HD 104237C is the lowest mass member of ɛ Cha with an estimated mass of ~13-15 Jupiter masses. The very low mass stars USNO-B120144.7 and 2MASS J12005517 show globally depleted spectral energy distributions, pointing at strong dust settling. 2MASS J12014343 may have a disk with a very specific inclination, where the central star is effectively screened by the cold outer parts of a flared disk, but the 10 μm radiation of the warm inner disk can still reach us. We find that the disks in sparse stellar associations are dissipated more slowly than those in denser (cluster) environments. We detect C2H2 rovibrational band around 13.7 μm on the IRS spectrum of USNO-B120144.7. We find strong signatures of grain growth and crystallization in all ɛ Cha members with 10 μm features detected in their IRS spectra. We combine the dust properties derived in the ɛ Cha sample with those found using identical or similar methods in the MBM 12, Coronet, η Cha associations, and in the cores-to-disks legacy program. We find that disks around low-mass young stars show a negative radial gradient in the mass-averaged grain size and mass fraction of crystalline silicates. A positive correlation exists between the mass-averaged grain sizes of amorphous silicates and the accretion rates if the latter is above ~10-9 M⊙ yr-1, possibly indicating that those disks are sufficiently turbulent to prevent grains of several microns in size to sink into the disk interior. Based on observations performed at ESO's La Silla-Paranal observatory under programme 076.C-0470.

UCAC and URAT: Optical Astrometric Catalog Observing Programs

DTIC Science & Technology

2010-09-21

12 100 K 1.0 1997 Tycho-2 G/S yes <= 12 2.5 M 10..100 2000 UCAC G yes 8..16 100 M 20.. 70 2004+ 2MASS G no IR...UCAC3 G yes 8..16 100 M 20.. 70 2009 first CCD survey 2MASS G no IR 500 M 90 2003 1 epoch USNO-B G yes 12..21 1000 M 200 2003 Schmidt plates PanSTARRS G

Parallax and Luminosity Measurements of an L SubDwarf

DTIC Science & Technology

2008-01-10

parallax and luminosity measurements for an L subdwarf, the sdL7 2MASS J05325346+ 8246465. Observations conducted over 3 years by the USNO infrared...comparable to mid-type L field dwarfs. Comparison of the luminosity of 2MASS J05325346+8246465 to theoretical evolutionary models indicates that its...The relatively bright J-bandmagnitude of 2MASS J05325346+8246465 implies significantly reduced opacity in the 1.2 m region, consistent with inhibited

Precision Astrometry of the Exoplanet Host Candidate GD 66

DTIC Science & Technology

2012-01-01

companions, including very low mass stars, neutron stars and black holes , for orbital pe- riods p > 4 yr. Remarkably, a period-dependent range of...trend in the pulsation arrival times cannot be due to stellar -mass secondaries, which include low-mass stars, white dwarfs, neutron stars and black ... holes with periods longer than 4 yr. The USNO relative astrometric monitoring of just over a decade rules out stellar -mass, dark companions with periods

The Very Red Afterglow of GRB 000418: Further Evidence for Dust Extinction in a Gamma-Ray Burst Host Galaxy

NASA Astrophysics Data System (ADS)

Klose, S.; Stecklum, B.; Masetti, N.; Pian, E.; Palazzi, E.; Henden, A. A.; Hartmann, D. H.; Fischer, O.; Gorosabel, J.; Sánchez-Fernández, C.; Butler, D.; Ott, Th.; Hippler, S.; Kasper, M.; Weiss, R.; Castro-Tirado, A.; Greiner, J.; Bartolini, C.; Guarnieri, A.; Piccioni, A.; Benetti, S.; Ghinassi, F.; Magazzú, A.; Hurley, K.; Cline, T.; Trombka, J.; McClanahan, T.; Starr, R.; Goldsten, J.; Gold, R.; Mazets, E.; Golenetskii, S.; Noeske, K.; Papaderos, P.; Vreeswijk, P. M.; Tanvir, N.; Oscoz, A.; Muñoz, J. A.; Castro Cerón, J. M.

2000-12-01

We report near-infrared and optical follow-up observations of the afterglow of the GRB 000418 starting 2.5 days after the occurrence of the burst and extending over nearly 7 weeks. GRB 000418 represents the second case for which the afterglow was initially identified by observations in the near-infrared. During the first 10 days its R-band afterglow was well characterized by a single power-law decay with a slope of 0.86. However, at later times the temporal evolution of the afterglow flattens with respect to a simple power-law decay. Attributing this to an underlying host galaxy, we find its magnitude to be R=23.9 and an intrinsic afterglow decay slope of 1.22. The afterglow was very red with R-K~4 mag. The observations can be explained by an adiabatic, spherical fireball solution and a heavy reddening due to dust extinction in the host galaxy. This supports the picture that (long) bursts are associated with events in star-forming regions. Based on observations collected at the Bologna Astronomical Observatory in Loiano, Italy; at the TNG, Canary Islands, Spain; at the German-Spanish Astronomical Centre, Calar Alto, operated by the Max-Planck-Institut for Astronomy, Heidelberg, jointly with the Spanish National Commission for Astronomy; at the US Naval Observatory; and at the UK Infrared Telescope.

The binary white dwarf LHS 3236

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, Hugh C.; Dahn, Conard C.; Canzian, Blaise

2013-12-10

The white dwarf LHS 3236 (WD1639+153) is shown to be a double-degenerate binary, with each component having a high mass. Astrometry at the U.S. Naval Observatory gives a parallax and distance of 30.86 ± 0.25 pc and a tangential velocity of 98 km s{sup –1}, and reveals binary orbital motion. The orbital parameters are determined from astrometry of the photocenter over more than three orbits of the 4.0 yr period. High-resolution imaging at the Keck Observatory resolves the pair with a separation of 31 and 124 mas at two epochs. Optical and near-IR photometry give a set of possible binarymore » components. Consistency of all data indicates that the binary is a pair of DA stars with temperatures near 8000 and 7400 K and with masses of 0.93 and 0.91 M {sub ☉}; also possible is a DA primary and a helium DC secondary with temperatures near 8800 and 6000 K and with masses of 0.98 and 0.69 M {sub ☉}. In either case, the cooling ages of the stars are ∼3 Gyr and the total ages are <4 Gyr. The combined mass of the binary (1.66-1.84 M {sub ☉}) is well above the Chandrasekhar limit; however, the timescale for coalescence is long.« less

32 CFR 700.406 - Naval Vessel Register, classification of naval craft, and status of ships and service craft.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Naval Vessel Register, classification of naval... STATES NAVY REGULATIONS AND OFFICIAL RECORDS The Chief of Naval Operations § 700.406 Naval Vessel Register, classification of naval craft, and status of ships and service craft. (a) The Chief of Naval...

32 CFR 700.406 - Naval Vessel Register, classification of naval craft, and status of ships and service craft.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Naval Vessel Register, classification of naval... STATES NAVY REGULATIONS AND OFFICIAL RECORDS The Chief of Naval Operations § 700.406 Naval Vessel Register, classification of naval craft, and status of ships and service craft. (a) The Chief of Naval...

The Phases Differential Astrometry Data Archive. 4. The Triple Star Systems 63 Gem A and HR 2896

DTIC Science & Technology

2010-12-01

3450 Massachusetts Avenue, NW, Washington, DC 20392-5420, USA; wih @usno.navy.mil 5 Division of Physics, Mathematics and Astronomy, 105-24, California...presented to aid in constraining the orbit and measuring the stellar masses. In fact, 63 Gem itself is a sextuple system: the hierarchical triple...that mutual inclination measurements have been rare is because of the observational challenges these sys- tems present. RV signals are largest for

An NTP Stratum-One Server Farm Fed By IEEE-1588

DTIC Science & Technology

2010-01-01

Serial Time Code Formats,” U.S. Army White Sands Missile Range, N.M. [11] J. Eidson , 2005, “IEEE-1588 Standard for a Precision Clock Synchronization ... synchronized to its Master Clocks via IRIG-B time code on a low- frequency RF distribution system. The availability of Precise Time Protocol (PTP, IEEE...forwarding back to the requestor. The farm NTP servers are synchronized to the USNO Master Clocks using IRIG-B time code. The current standard NTP

Precise time dissemination via portable atomic clocks

NASA Technical Reports Server (NTRS)

Putkovich, K.

1982-01-01

The most precise operational method of time dissemination over long distances presently available to the Precise Time and Time Interval (PTTI) community of users is by means of portable atomic clocks. The Global Positioning System (GPS), the latest system showing promise of replacing portable clocks for global PTTI dissemination, was evaluated. Although GPS has the technical capability of providing superior world-wide dissemination, the question of present cost and future accessibility may require a continued reliance on portable clocks for a number of years. For these reasons a study of portable clock operations as they are carried out today was made. The portable clock system that was utilized by the U.S. Naval Observatory (NAVOBSY) in the global synchronization of clocks over the past 17 years is described and the concepts on which it is based are explained. Some of its capabilities and limitations are also discussed.

VizieR Online Data Catalog: Identifications of Sonneberg variables (Kinnunen+, 1999-2000)

NASA Astrophysics Data System (ADS)

Kinnunen, T.; Skiff, B. A.

2002-09-01

The list below is a continuation of a series providing accurate positions and identifications for variables appearing on the MVS charts (Hoffmeister, 1957, Mitt. Verdander. Sterne, No. 245). The variables here were first described by Hoffmeister (1949, Astron. Abh. Ergaenzungshefte z.d. Astron. Nach., 12, no. 1, A3) in the difficult-to-find ``Ergaenzungshefte'' to the Astronomische Nachrichten, and are the first group from a collection of some 1440 variables from this publication. Details about the identification procedure and table layout are contained in the first report of our series (Kinnunen & Skiff, 2000IBVS.4862....1K). We are grateful to librarians Antoinette Beiser (Lowell) and Brenda Corbin (U. S. Naval Observatory, Washington) for providing a photocopy of the Hoffmeister survey; ``bibliothecaire extraordinaire'' Suzanne Laloe (Obs. Paris-Meudon) advised on how this obscure journal should be cited. (3 data files).

Space Studies Board, 1994

NASA Technical Reports Server (NTRS)

1995-01-01

This 1994 report of the Space Studies Board of the National Research Council summarizes the charter and organization of the board, activities and membership, major and short reports, and congressional testimony. A cumulative bibliography of the Space Studies (formerly Space Science) Board and its committees is provided. An appendix contains reports of the panel to review Earth Observing System Data and Information System (EOSDIS) plans. Major reports cover scientific opportunities in the human exploration of space, the dichotomy between funding and effectiveness in space physics, an integrated strategy for the planetary sciences for the years 1995-2010, and Office of Naval Research (ONR) research opportunities in upper atmospheric sciences. Short reports cover utilization of the space station, life and microgravity sciences and the space station program, Space Infrared Telescope Facility and the Stratospheric Observatory for Infrared Astronomy, and the Advanced X-ray Astrophysics Facility and Cassini Saturn Probe.

Deep-space navigation applications of improved ground-based optical astrometry

NASA Technical Reports Server (NTRS)

Null, G. W.; Owen, W. M., Jr.; Synnott, S. P.

1992-01-01

Improvements in ground-based optical astrometry will eventually be required for navigation of interplanetary spacecraft when these spacecraft communicate at optical wavelengths. Although such spacecraft may be some years off, preliminary versions of the astrometric technology can also be used to obtain navigational improvements for the Galileo and Cassini missions. This article describes a technology-development and observational program to accomplish this, including a cooperative effort with U.S. Naval Observatory Flagstaff Station. For Galileo, Earth-based astrometry of Jupiter's Galilean satellites may improve their ephemeris accuracy by a factor of 3 to 6. This would reduce the requirements for onboard optical navigation pictures, so that more of the data transmission capability (currently limited by high-gain antenna deployment problems) can be used for science data. Also, observations of European Space Agency (ESA) Hipparcos stars with asteroid 243 Ida may provide significantly improved navigation accuracy for a planned August 1993 Galileo spacecraft encounter.

The Planetary and Eclipse Oil Paintings of Howard Russell Butler

NASA Astrophysics Data System (ADS)

Pasachoff, Jay M.; Olson, R. M.

2013-10-01

The physics-trained artist Howard Russell Butler (1856-1934) has inspired many astronomy students through his planetary and eclipse paintings that were long displayed at the Hayden Planetarium in New York, the Fels Planetarium at the Franklin Institute in Philadelphia, and the Buffalo Museum of Science. We discuss not only the eclipse triptychs (1918, 1923, and 1925) at each of those institutions but also his paintings of Mars as seen from Phobos and from Deimos (with landscapes of those moons in the foreground depicted in additional oils hung at Princeton University) and the Earth from our Moon. We also describe his involvement with astronomy and his unique methodology that allowed him to surpass the effects then obtainable with photography, as well as his inclusion in a U.S. Naval Observatory eclipse expedition in 1918, as well as his auroral, solar-prominence, and 1932-eclipse paintings.

All chain Loran-C time synchronization

NASA Technical Reports Server (NTRS)

Sherman, H. T.

1973-01-01

A program is in progress to implement coordinated universal time (UTC) synchronization on all Loran-C transmissions. The present capability is limited to five Loran-C chains in which the tolerance is twenty-five microseconds with respect to UTC. Upon completion of the program, the transmissions of all Loran-C chains will be maintained within five microseconds of UTC. The improvement plan consists of equipping selected Loran-C transmitting stations for greater precision of frequency standard adjustment and improved monitoring capability. External time monitor stations will utilize television time transfer techniques with nearby SATCOM terminals where practicable, thus providing the requisite traceability to the Naval Observatory. The monitor equipment groups and the interrelationships with the ground station equipment are discussed. After a brief review of control doctrine, forth-coming improvements to transmitting stations and how the time monitor and navigation equipments will complement each other resulting in improved service to all users of the Loran-C system are described.

33 CFR 334.300 - Hampton Roads and Willoughby Bay, Norfolk Naval Base, naval restricted area, Norfolk, Virginia.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Norfolk Naval Base, naval restricted area, Norfolk, Virginia. 334.300 Section 334.300 Navigation and... RESTRICTED AREA REGULATIONS § 334.300 Hampton Roads and Willoughby Bay, Norfolk Naval Base, naval restricted...′22″ W at the Naval Air Station. (2) Beginning at a point on the Naval Station shore at latitude 36°56...

78 FR 72025 - Security Zones; Naval Base Point Loma; Naval Mine Anti Submarine Warfare Command; San Diego Bay...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-02

...-AA87 Security Zones; Naval Base Point Loma; Naval Mine Anti Submarine Warfare Command; San Diego Bay... establishing a new security zone at the Naval Mine and Anti-Submarine Warfare Command to protect the relocated... Commander of Naval Base Point Loma, the Commander of the Naval Mine Anti Submarine Warfare Command, and the...

33 CFR 334.360 - Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Virginia; restricted area, U.S. Naval Base and Naval Surface Weapon Center. 334.360 Section 334.360....S. Naval Base and Naval Surface Weapon Center. (a) The area. Beginning at latitude 37°01′03... Manager, Naval Surface Warfare Center, Dahlgren Division Coastal Systems Station Detachment, Fort Monroe...

33 CFR 334.360 - Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Virginia; restricted area, U.S. Naval Base and Naval Surface Weapon Center. 334.360 Section 334.360....S. Naval Base and Naval Surface Weapon Center. (a) The area. Beginning at latitude 37°01′03... Manager, Naval Surface Warfare Center, Dahlgren Division Coastal Systems Station Detachment, Fort Monroe...

Optical Monitoring Observations of AQL X-1

NASA Astrophysics Data System (ADS)

Guver, Tolga; Kunder, Andrea; Ozel, Feryal

2010-09-01

AQL X-1 has been in a bright outburst in the X-rays and optical since September 1st and 7th (Atel #2850, #2871). We report on our observations of the source on September 26th UTC with the 4m CTIO BLANCO Telescope. Using MOSAIC II detector we obtained 3 R band images with exposure times of 200 seconds. We converted instrumental magnitudes to the standard system using several nearby stars and the USNO B1.0 catalog (Monet et al.

Swift J1822.3-1606: Enhanced Swift-XRT position

NASA Astrophysics Data System (ADS)

Pagani, C.; Beardmore, A. P.; Kennea, J. A.

2011-07-01

Using 1046 s of XRT Photon Counting mode data and 1 UVOT image for Swift J1822.3-1606, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue) of RA, Dec = 275.57500, -16.07412 which is equivalent to: RA (J2000): 18h 22m 18.00s Dec (J2000): -16d 04' 26.8" with an uncertainty of 1.8 arcsec (radius, 90% confidence).

USNO GPS program

NASA Technical Reports Server (NTRS)

Putkovich, K.

1981-01-01

Initial test results indicated that the Global Positioning System/Time Transfer Unit (GPS/TTU) performed well within the + or - 100 nanosecond range required by the original system specification. Subsequent testing involved the verification of GPS time at the master control site via portable clocks and the acquisition and tracking of as many passes of the space vehicles currently in operation as possible. A description and discussion of the testing, system modifications, test results obtained, and an evaluation of both GPS and the GPS/TTU are presented.

Double Stars in the USNO CCD Astrograpic Catalog

DTIC Science & Technology

2013-10-01

Catalog (UCAC; Zacharias et al. 2013) is a compiled, all-sky star catalog covering mainly the 8 –16 mag range in a single bandpass between V and R...for UCAC were obtained using the USNO’s 1970s vintage 8 inch Twin Astrograph, originally designed for photographic survey work. The astrograph has two...lens was designed for 8 × 10 inch photographic plates and gives a 9◦ field of view, only the∼1 deg2 area covered by the single CCD was used for the

Definitions of Frequency and Timing Terms, Satellite Navigation and Timing Systems, and the Behavior and Analyses of Precision Crystal and Atomic Frequency Standards and their Characteristics

DTIC Science & Technology

2009-05-01

time transfer techniques has largely been due to the improvement in frequency standards. In this document, an effort was made to provide substantial...of RCC Document 214-94, contains definitions of frequency and timing terms, time transfer techniques and analysis, and behavior of crystal and atomic...Characteristics, May 2009 viii TTG Telecommunications and Timing Group TWSTFT Two-Way Satellite Time and Frequency Transfer U.S. United States USNO

Automated Delay Measurement System for an Earth Station for Two-Way Satellite Time and Frequency Transfer

DTIC Science & Technology

1994-12-01

important for improving the TWSTFT capabilities. An automnted system for this purpose has been developed from the initial design at NMi-VSL. It...September 1994 together with a USNO portable station on a calibration trip to European TWSTFT earth staions. 1. Introduction The Two-Way Satellite...Time and Frequency Transfer ( TWSTFT ) method (Fig. I) is used to compare two clocks or time scales which are often located at great distances from each

First Results on a Transatlantic Time and Frequency Transfer by GPS Carrier Phase

DTIC Science & Technology

1998-12-01

Washington (USNO). Besides the longer baseline the choice of these two sites offers aho the possibility to compare frequently GeTT and TWSTFT . The paper...INTRODUCTION The GPS Common View (CV) and thc Two Way Satellite Time and Frequency Transfer ( TWSTFT ) are up to now the most used methods for precise tirnc... TWSTFT technique allows comparisons with a shorter trme but at the prize of heavy sending and receiving equipment on each site An interesting

PTB’S Time and Frequency Activities in 2006: New DCF77 Electronics, New NTP Servers, and Calibration Activities

DTIC Science & Technology

2007-01-01

PTTI) Meeting ( TWSTFT ) is being routinely performed with several European and US stations. On the initiative of NICT, a TWSTFT link was...During the last 2 years, PTB has upgraded its TWSTFT and GPS capabilities in order to achieve better reliability and robustness against system failures...NTP-server, and, briefly, the calibration of the international time links, i.e. the result of the latest calibration of the TWSTFT links to the USNO

Optical Positions of ICRF Sources from CTIO 1.0M Data

DTIC Science & Technology

2015-01-01

proyecto del USNO para enlazar los sistemas de referencia en radio y óptico, se tomaron datos con el telescopio CTIO de 1.0 m in 2009. Los primeros...subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE...AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES RevMexAA (Serie de Conferencias), 46, 83â\\ග (2015) 14

77 FR 60678 - Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training and Testing...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-04

...-submarine warfare; mine warfare; naval special warfare; Naval Air Systems Command (NAVAIR) testing; Naval Sea Systems Command (NAVSEA) testing; Space and Naval Warfare Systems Command (SPAWAR) testing; and Office of Naval Research (ONR) and Naval Research Laboratory (NRL) testing. Detailed descriptions of...

Source Hierarchy List. Volume 3. O through Z

DTIC Science & Technology

1994-07-01

NAVAL WEAPONS CENTER CHINA LAKE CA MARINE AVIATION DETACHMENT* 07 NAVAL WEAPONS CENTER CORONA ANNEX CA 08 NAVAL ORDNANCE LAB CORONA CA 08 NAVAL...WEAPONS CENTER CORONA LABS CA 05 NAVAL AIR WEAPONS STATION CHINA LAKE CA 05 PACIFIC MISSILE TEST CENTER POINT MUGU CA 06 AIR DEVELOPMENT SQUADRON FOUR...INDIAN HEAD MD 03 NAVAL ORDNANCE CENTER INDIAN HEAD MO 04 NAVAL WARFARE ASSESSMENT CENTER CORONA CA 05 FLEET ANALYSIS CENTER CORONA CA 03

33 CFR 110.215 - Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach, California; Naval...

Code of Federal Regulations, 2011 CFR

2011-07-01

....S. Naval Weapons Station, Seal Beach, California; Naval Explosives Anchorage. 110.215 Section 110... REGULATIONS Anchorage Grounds § 110.215 Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach... permission from the Commanding Officer, Naval Weapons Station, Seal Beach, California. This officer will...

33 CFR 110.215 - Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach, California; Naval...

Code of Federal Regulations, 2010 CFR

2010-07-01

....S. Naval Weapons Station, Seal Beach, California; Naval Explosives Anchorage. 110.215 Section 110... REGULATIONS Anchorage Grounds § 110.215 Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach... permission from the Commanding Officer, Naval Weapons Station, Seal Beach, California. This officer will...

33 CFR 110.215 - Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach, California; Naval...

Code of Federal Regulations, 2012 CFR

2012-07-01

....S. Naval Weapons Station, Seal Beach, California; Naval Explosives Anchorage. 110.215 Section 110... REGULATIONS Anchorage Grounds § 110.215 Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach... permission from the Commanding Officer, Naval Weapons Station, Seal Beach, California. This officer will...

33 CFR 110.215 - Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach, California; Naval...

Code of Federal Regulations, 2014 CFR

2014-07-01

....S. Naval Weapons Station, Seal Beach, California; Naval Explosives Anchorage. 110.215 Section 110... REGULATIONS Anchorage Grounds § 110.215 Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach... permission from the Commanding Officer, Naval Weapons Station, Seal Beach, California. This officer will...

33 CFR 110.215 - Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach, California; Naval...

Code of Federal Regulations, 2013 CFR

2013-07-01

....S. Naval Weapons Station, Seal Beach, California; Naval Explosives Anchorage. 110.215 Section 110... REGULATIONS Anchorage Grounds § 110.215 Anaheim Bay Harbor, California; U.S. Naval Weapons Station, Seal Beach... permission from the Commanding Officer, Naval Weapons Station, Seal Beach, California. This officer will...

33 CFR 334.1215 - Port Gardner, Everett Naval Base, naval restricted area, Everett, Washington.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Port Gardner, Everett Naval Base, naval restricted area, Everett, Washington. 334.1215 Section 334.1215 Navigation and Navigable Waters... REGULATIONS § 334.1215 Port Gardner, Everett Naval Base, naval restricted area, Everett, Washington. (a) The...

33 CFR 334.81 - Narragansett Bay, East Passage, Coddington Cove, Naval Station Newport, naval restricted area...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Coddington Cove, Naval Station Newport, naval restricted area, Newport, Rhode Island. 334.81 Section 334.81... AND RESTRICTED AREA REGULATIONS § 334.81 Narragansett Bay, East Passage, Coddington Cove, Naval Station Newport, naval restricted area, Newport, Rhode Island. (a) The area. All of the navigable waters...

33 CFR 334.81 - Narragansett Bay, East Passage, Coddington Cove, Naval Station Newport, naval restricted area...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Coddington Cove, Naval Station Newport, naval restricted area, Newport, Rhode Island. 334.81 Section 334.81... AND RESTRICTED AREA REGULATIONS § 334.81 Narragansett Bay, East Passage, Coddington Cove, Naval Station Newport, naval restricted area, Newport, Rhode Island. (a) The area. All of the navigable waters...

U.S. Naval Base, Pearl Harbor, Naval Ammunition Depot West Loch, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

U.S. Naval Base, Pearl Harbor, Naval Ammunition Depot West Loch, Oahu, Dispensary, Near Avenue A between First & Second Streets, Lualualei, West Loch Branch Naval Magazine, Pearl City, Honolulu County, HI

33 CFR 334.300 - Hampton Roads and Willoughby Bay, Norfolk Naval Base, naval restricted area, Norfolk, Virginia.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Hampton Roads and Willoughby Bay, Norfolk Naval Base, naval restricted area, Norfolk, Virginia. 334.300 Section 334.300 Navigation and... RESTRICTED AREA REGULATIONS § 334.300 Hampton Roads and Willoughby Bay, Norfolk Naval Base, naval restricted...

Naval Medical Research and Development Strategic Plan

DTIC Science & Technology

2008-03-01

readiness of Navy and Marine Corps aviators. Undersea Medicine NMR&D conducts research in submariner health and safety, disabled submarine...humanitarian deployment to Latin America and the Caribbean. Naval-unique areas include undersea medicine (submarine and diving medicine), expeditionary and...Result Areas 1. Naval Aviation Enterprise (NAE) 2. Naval Surface Warfare Enterprise (SWE) 3. Naval Undersea Enterprise (USE) 4. Naval

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. (a) The area. The waters within the Naval Station Annapolis small boat basin and...

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. (a) The area. The waters within the Naval Station Annapolis small boat basin and...

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. (a) The area. The waters within the Naval Station Annapolis small boat basin and...

The 2011 June 23 Stellar Occultation by Pluto: Airborne and Ground Observations

NASA Astrophysics Data System (ADS)

Person, M. J.; Dunham, E. W.; Bosh, A. S.; Levine, S. E.; Gulbis, A. A. S.; Zangari, A. M.; Zuluaga, C. A.; Pasachoff, J. M.; Babcock, B. A.; Pandey, S.; Amrhein, D.; Sallum, S.; Tholen, D. J.; Collins, P.; Bida, T.; Taylor, B.; Bright, L.; Wolf, J.; Meyer, A.; Pfueller, E.; Wiedemann, M.; Roeser, H.-P.; Lucas, R.; Kakkala, M.; Ciotti, J.; Plunkett, S.; Hiraoka, N.; Best, W.; Pilger, E. J.; Micheli, M.; Springmann, A.; Hicks, M.; Thackeray, B.; Emery, J. P.; Tilleman, T.; Harris, H.; Sheppard, S.; Rapoport, S.; Ritchie, I.; Pearson, M.; Mattingly, A.; Brimacombe, J.; Gault, D.; Jones, R.; Nolthenius, R.; Broughton, J.; Barry, T.

2013-10-01

On 2011 June 23, stellar occultations by both Pluto (this work) and Charon (future analysis) were observed from numerous ground stations as well as the Stratospheric Observatory for Infrared Astronomy (SOFIA). This first airborne occultation observation since 1995 with the Kuiper Airborne Observatory resulted in the best occultation chords recorded for the event, in three visible wavelength bands. The data obtained from SOFIA are combined with chords obtained from the ground at the IRTF, the U.S. Naval Observatory Flagstaff Station, and Leeward Community College to give the detailed state of the Pluto-Charon system at the time of the event with a focus on Pluto's atmosphere. The data show a return to the distinct upper and lower atmospheric regions with a knee or kink in the light curve separating them as was observed in 1988, rather than the smoothly transitioning bowl-shaped light curves of recent years. The upper atmosphere is analyzed by fitting a model to all of the light curves, resulting in a half-light radius of 1288 ± 1 km. The lower atmosphere is analyzed using two different methods to provide results under the differing assumptions of particulate haze and a strong thermal gradient as causes for the lower atmospheric diminution of flux. These results are compared with those from past occultations to provide a picture of Pluto's evolving atmosphere. Regardless of which lower atmospheric structure is assumed, results indicate that this part of the atmosphere evolves on short timescales with results changing the light curve structures between 1988 and 2006, and then reverting these changes in 2011 though at significantly higher pressures. Throughout these changes, the upper atmosphere remains remarkably stable in structure, again except for the overall pressure changes. No evidence of onset of atmospheric collapse predicted by frost migration models is seen, and the atmosphere appears to be remaining at a stable pressure level, suggesting it should persist at this full level through New Horizon's flyby in 2015.

Knowing Our Neighbors: Fundamental Properties of Nearby Stars

NASA Astrophysics Data System (ADS)

Bartlett, Jennifer L.; Ianna, P. A.; Henry, T. J.; Begam, M. C.; Jao, W.; Subasavage, J. P., Jr.; Nearby Stars, Research Consortium on

2007-12-01

Although the stars within 25 pc of the Sun constitute the one stellar sample that we can aspire to know thoroughly, we continue identifying objects closer than 10 pc. We know even less about local substellar populations, especially planets. The Cerro Tololo Inter-American Observatory Parallax Investigation (CTIOPI) is observing 31 late-type, red dwarfs selected for my thesis as part of a larger effort to complete the nearby star census. Preliminary parallaxes substantiate distances less than 25 pc for at least 28 stars. Of these, LP 991-84, LHS 6167, and LP 876-10 may lie within 10 pc. Preliminary proper motions for all but three stars exceed 0.2” yr-1. One recently established neighbor, LP 869-26, also appears to be a new binary. Associated VRI photometry and spectroscopy are in progress as well. Many of these stars are potential targets for astrometric planet searches, such as the Space Interferometry Mission (SIM). In addition to confirming solar neighborhood membership, astrometry can discover brown dwarfs and planets. Time-series analyses of residuals to the UVa Southern Parallax Program (SPP) observations are contributing to frequency and distribution data for nearby substellar objects. In particular, LHS 288 displays an intriguing signal, which might be caused by a very low-mass companion. Twelve other SPP stars demonstrate no significant perturbations. Finally, re-analyzing the Leander McCormick Observatory photographic plates of Barnard's Star failed to detect any planets orbiting it. This study of more than 900 exposures was sensitive to bodies of 2.2 Jupiter masses or more. NSF grants AST 98-20711 and 05-07711, GSU, NASA-SIM, Litton Marine Systems, UVa, Hampden-Sydney College, US Naval Observatory, and the Levinson Fund of the Peninsula Community Foundation supported this research. The ANU Research School of Astronomy & Astrophysics allocated observing time generously. CTIOPI was an NOAO Survey Program and continues as part of the SMARTS Consortium.

THE 2011 JUNE 23 STELLAR OCCULTATION BY PLUTO: AIRBORNE AND GROUND OBSERVATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Person, M. J.; Bosh, A. S.; Levine, S. E.

On 2011 June 23, stellar occultations by both Pluto (this work) and Charon (future analysis) were observed from numerous ground stations as well as the Stratospheric Observatory for Infrared Astronomy (SOFIA). This first airborne occultation observation since 1995 with the Kuiper Airborne Observatory resulted in the best occultation chords recorded for the event, in three visible wavelength bands. The data obtained from SOFIA are combined with chords obtained from the ground at the IRTF, the U.S. Naval Observatory Flagstaff Station, and Leeward Community College to give the detailed state of the Pluto-Charon system at the time of the event withmore » a focus on Pluto's atmosphere. The data show a return to the distinct upper and lower atmospheric regions with a knee or kink in the light curve separating them as was observed in 1988, rather than the smoothly transitioning bowl-shaped light curves of recent years. The upper atmosphere is analyzed by fitting a model to all of the light curves, resulting in a half-light radius of 1288 {+-} 1 km. The lower atmosphere is analyzed using two different methods to provide results under the differing assumptions of particulate haze and a strong thermal gradient as causes for the lower atmospheric diminution of flux. These results are compared with those from past occultations to provide a picture of Pluto's evolving atmosphere. Regardless of which lower atmospheric structure is assumed, results indicate that this part of the atmosphere evolves on short timescales with results changing the light curve structures between 1988 and 2006, and then reverting these changes in 2011 though at significantly higher pressures. Throughout these changes, the upper atmosphere remains remarkably stable in structure, again except for the overall pressure changes. No evidence of onset of atmospheric collapse predicted by frost migration models is seen, and the atmosphere appears to be remaining at a stable pressure level, suggesting it should persist at this full level through New Horizon's flyby in 2015.« less

Some Operational Aspects of the International Two-Way Satellite Time and Frequency Transfer (TWSTFT) Experiment Using INTELSAT Satellites at 307 Degrees East

NASA Technical Reports Server (NTRS)

DeYoung, J. A.; McKinley, A.; Davis, J. A.; Hetzel, P.; Bauch, A.

1996-01-01

Eight laboratories are participating in an international two-way satellite time and frequency transfer (TWSTFT) experiment. Regular time and frequency transfers have been performed over a period of almost two years, including both European and transatlantic time transfers. The performance of the regular TWSTFT sessions over an extended period has demonstrated conclusively the usefulness of the TWSTFT method for routine international time and frequency comparisons. Regular measurements are performed three times per week resulting in a regular but unevenly spaced data set. A method is presented that allows an estimate of the values of delta (sub y)(gamma) to be formed from these data. In order to maximize efficient use of paid satellite time an investigation to determine the optimal length of a single TWSTFT session is presented. The optimal experiment length is determined by evaluating how long white phase modulation (PM) instabilities are the dominant noise source during the typical 300-second sampling times currently used. A detailed investigation of the frequency transfers realized via the transatlantic TWSTFT links UTC(USNO)-UTC(NPL), UTC(USNO)-UTC(PTB), and UTC(PTB)-UTC(NPL) is presented. The investigation focuses on the frequency instabilities realized, a three cornered hat resolution of the delta (sub y) (gamma) values, and a comparison of the transatlantic and inter-European determination of UTC(PTB)-UTC(NPL). Future directions of this TWSTFT experiment are outlined.

Naval Warfare

DTIC Science & Technology

2010-03-01

Naval Doctrine Publication 1 Naval Warfare March 2010 Doctrine The only satisfactory method of ensuring unity of effort lies in due...LCDR Dudley W. Knox, USN “The Role of Doctrine in Naval Warfare” U.S. Naval Institute Proceedings, 1915 01 March 2010 FOREWORD United States (US...naval doctrine is the foundation upon which our tactics, techniques, and procedures are built. It articulates operational concepts that govern the

33 CFR 334.160 - Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval restricted area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval restricted area. 334.160 Section 334.160 Navigation and... RESTRICTED AREA REGULATIONS § 334.160 Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval...

33 CFR 334.820 - Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. 334.820 Section 334.820 Navigation and Navigable... REGULATIONS § 334.820 Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. (a...

33 CFR 334.820 - Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. 334.820 Section 334.820 Navigation and Navigable... REGULATIONS § 334.820 Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. (a...

33 CFR 334.160 - Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval restricted area. 334.160 Section 334.160 Navigation and... RESTRICTED AREA REGULATIONS § 334.160 Severn River, at U.S. Naval Academy Santee Basin, Annapolis, Md.; naval...

75 FR 53958 - Meeting of the Board of Advisors to the Presidents of the Naval Postgraduate School and the Naval...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

... DEPARTMENT OF DEFENSE Department of the Navy Meeting of the Board of Advisors to the Presidents of the Naval Postgraduate School and the Naval War College AGENCY: Department of the Navy, DoD. ACTION... of Advisors (BOA) to the Presidents of the Naval Postgraduate School (NPS) and the Naval War College...

77 FR 57562 - Meeting of the Board of Advisors to The Presidents of the Naval Postgraduate School and the Naval...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-18

... DEPARTMENT OF DEFENSE Department of the Navy Meeting of the Board of Advisors to The Presidents of the Naval Postgraduate School and the Naval War College AGENCY: Department of the Navy, DoD. ACTION...) to the Presidents of the Naval Postgraduate School (NPS) and the Naval War College (NWC) and its...

33 CFR 334.360 - Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface Weapon Center. 334.360 Section 334.360....S. Naval Base and Naval Surface Weapon Center. (a) The area. Beginning at latitude 37°01′03...

33 CFR 334.360 - Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface Weapon Center. 334.360 Section 334.360....S. Naval Base and Naval Surface Weapon Center. (a) The area. Beginning at latitude 37°01′03...

33 CFR 334.360 - Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Chesapeake Bay off Fort Monroe, Virginia; restricted area, U.S. Naval Base and Naval Surface Weapon Center. 334.360 Section 334.360....S. Naval Base and Naval Surface Weapon Center. (a) The area. Beginning at latitude 37°01′03...

32 CFR 705.5 - Taking of photos on board naval ships, aircraft and installations by members of the general public.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Taking of photos on board naval ships, aircraft... AFFAIRS REGULATIONS § 705.5 Taking of photos on board naval ships, aircraft and installations by members... naval ship or aircraft or into a naval activity or to take photographs within a naval jurisdiction...

The Health of Naval Recruits: Dental Caries.

DTIC Science & Technology

1980-05-01

AA086 185 NAVAL DENTAL RESEARCH INST GREAT LAKES IL F/G 6/5 THE HEALTH OF NAVAL RECRUITSI DENTAL CARIES .(U) MAY 80 J C CECIL, M R WIRTHLIN, R G...WALTER UANLASSIF I O I-R-80-O5 In EIiIIEEEEI EEEEIIIIEEEIIEflfll..o YrIf NDRI-PR 80-05 May 1980 00 THE HEALTH OF NAVAL RECRUITS: 4 DENTAL CARIES BY M. R...80 6 30 M18--777= NAVAL DENTAL RESEARCH INSTITUTE NAVAL BASE, BLDG. 1-H GREAT LAKES, ILLINOIS 60088 The Health of Naval Recruits: Dental Caries J. C

33 CFR 334.610 - Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone. 334.610 Section 334.610 Navigation and... RESTRICTED AREA REGULATIONS § 334.610 Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted...

33 CFR 334.610 - Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone. 334.610 Section 334.610 Navigation and... RESTRICTED AREA REGULATIONS § 334.610 Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted...

33 CFR 334.610 - Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone. 334.610 Section 334.610 Navigation and... RESTRICTED AREA REGULATIONS § 334.610 Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted...

33 CFR 334.610 - Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted areas and danger zone. 334.610 Section 334.610 Navigation and... RESTRICTED AREA REGULATIONS § 334.610 Key West Harbor, at U.S. Naval Base, Key West, Fla.; naval restricted...

32 CFR 724.407 - Commander, Naval Reserve Force.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Commander, Naval Reserve Force. 724.407 Section 724.407 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Reserve Force. Manages Naval Reserve resources. Responsible for providing limited support to the...

32 CFR 724.403 - President, Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false President, Naval Discharge Review Board. 724.403 Section 724.403 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Discharge Review Board. Supervises the Naval Discharge Review Board. (See subpart C). ...

32 CFR 724.407 - Commander, Naval Reserve Force.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Commander, Naval Reserve Force. 724.407 Section 724.407 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Reserve Force. Manages Naval Reserve resources. Responsible for providing limited support to the...

32 CFR 724.403 - President, Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false President, Naval Discharge Review Board. 724.403 Section 724.403 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Discharge Review Board. Supervises the Naval Discharge Review Board. (See subpart C). ...

32 CFR 724.303 - Functions: President, Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Functions: President, Naval Discharge Review... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Director, Secretary of the Navy Council of Review Boards and President Naval Discharge Review Board; Responsibilities in Support of the Naval Discharge Review Board...

32 CFR 724.303 - Functions: President, Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Functions: President, Naval Discharge Review... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Director, Secretary of the Navy Council of Review Boards and President Naval Discharge Review Board; Responsibilities in Support of the Naval Discharge Review Board...

33 CFR 334.260 - York River, Va.; naval restricted areas.

Code of Federal Regulations, 2014 CFR

2014-07-01

....; naval restricted areas. (a) The areas—(1) Naval mine service-testing area (prohibited). A rectangular...; and thence along the shore line to the point of beginning. (2) Naval mine service-testing area... case of emergency. Naval authorities are required to publish advance notice of mine-laying and/or...

33 CFR 334.260 - York River, Va.; naval restricted areas.

Code of Federal Regulations, 2013 CFR

2013-07-01

....; naval restricted areas. (a) The areas—(1) Naval mine service-testing area (prohibited). A rectangular...; and thence along the shore line to the point of beginning. (2) Naval mine service-testing area... case of emergency. Naval authorities are required to publish advance notice of mine-laying and/or...

32 CFR 724.203 - Broad objectives of naval discharge review.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Broad objectives of naval discharge review. 724... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.203 Broad objectives of naval discharge review. Naval discharge review shall have as its broad objectives: (a) The...

32 CFR 724.203 - Broad objectives of naval discharge review.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Broad objectives of naval discharge review. 724... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.203 Broad objectives of naval discharge review. Naval discharge review shall have as its broad objectives: (a) The...

32 CFR 724.203 - Broad objectives of naval discharge review.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Broad objectives of naval discharge review. 724... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.203 Broad objectives of naval discharge review. Naval discharge review shall have as its broad objectives: (a) The...

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Sinclair Inlet; naval restricted...; naval restricted areas. (a) Sinclair Inlet: naval restricted areas—(1) Area No. 1. All the waters of... Navy. No person, vessel, craft, article or thing, except those under supervision of military or naval...

33 CFR 334.1210 - Admiralty Inlet, entrance; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Admiralty Inlet, entrance; naval..., entrance; naval restricted area. (a) Admiralty Inlet, entrance; naval restricted area—(1) The area... prohibited. (ii) The regulations in this paragraph shall be enforced by the Commander, Naval Base, Seattle...

7 CFR 160.5 - Standards for naval stores.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Standards for naval stores. 160.5 Section 160.5..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.5 Standards for naval stores. In addition to the standards of...

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Sinclair Inlet; naval restricted...; naval restricted areas. (a) Sinclair Inlet: naval restricted areas—(1) Area No. 1. All the waters of... Navy. No person, vessel, craft, article or thing, except those under supervision of military or naval...

32 CFR 724.307 - Functions of the Commander, Naval Reserve Force.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Functions of the Commander, Naval Reserve Force... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Director, Secretary of the Navy Council of Review Boards and President Naval Discharge Review Board; Responsibilities in Support of the Naval Discharge Review Board...

33 CFR 334.1210 - Admiralty Inlet, entrance; naval restricted area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Admiralty Inlet, entrance; naval..., entrance; naval restricted area. (a) Admiralty Inlet, entrance; naval restricted area—(1) The area... prohibited. (ii) The regulations in this paragraph shall be enforced by the Commander, Naval Base, Seattle...

7 CFR 160.5 - Standards for naval stores.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Standards for naval stores. 160.5 Section 160.5..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.5 Standards for naval stores. In addition to the standards of...

32 CFR 724.101 - Naval Service.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Naval Service. 724.101 Section 724.101 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.101 Naval Service. The Naval Service is comprised of the uniformed members of the United...

32 CFR 724.101 - Naval Service.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Naval Service. 724.101 Section 724.101 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.101 Naval Service. The Naval Service is comprised of the uniformed members of the United...

32 CFR 724.203 - Broad objectives of naval discharge review.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Broad objectives of naval discharge review. 724... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.203 Broad objectives of naval discharge review. Naval discharge review shall have as its broad objectives: (a) The...

32 CFR 724.203 - Broad objectives of naval discharge review.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Broad objectives of naval discharge review. 724... PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.203 Broad objectives of naval discharge review. Naval discharge review shall have as its broad objectives: (a) The...

Soviet Naval Mission Assignments. Part 1. Soviet SSBN Roles in Strategic Strike

DTIC Science & Technology

1979-04-01

T^ 17. Captain First Rank Makeyev , Naval Science Candidate, Naval Digest, February 1977: "The Navy has acquired the cap- ability to deliver...34 (p. 19); 17. Captain First Rank Makeyev , Naval Science Candidate, Naval Digest, February 1977: "The Navy has acquired the cap- ability to

Butyltin Concentrations in Selected US Harbor Systems. A Baseline Assessment.

DTIC Science & Technology

1987-04-01

and the Naval Supply Center. Additionally. San Diego Bay is a multiple-use region that supports a commercial port, private shipyards, recreational...are Naval Air Station, Alameda; Naval Supply Center, Oakland: and Naval Station. Treasure Island. The Naval Support Activity at Mare Island is also...terminal on the west coast. The port is divided into three sections (figure 3). The Oakland Outer Harbor is situated to the north of the Naval Supply

The Concept of Fit in Contingency Theory.

DTIC Science & Technology

1984-11-01

Research Center San Diego, CA 92152 Psychology Department Naval Regional Medical Center San Diego, CA 92134 Com~’arding Officer - Naval Submarine Medical ...Research Laboratory Naval Submarine Base New London, Box 900 Grotcn, CT 06249 Co~anding Officer :;ava! Aerospace Medical Resea-:ch’ Lab Naval Air...Station Pen~sacola, FEL 32508 Program Manager for Human 44 Performance (Code 44) Naval Medical R&D Command National Naval Medical Center Bethesda, MD 20014A

Naval Waste Package Design Sensitivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

T. Schmitt

2006-12-13

The purpose of this calculation is to determine the sensitivity of the structural response of the Naval waste packages to varying inner cavity dimensions when subjected to a comer drop and tip-over from elevated surface. This calculation will also determine the sensitivity of the structural response of the Naval waste packages to the upper bound of the naval canister masses. The scope of this document is limited to reporting the calculation results in terms of through-wall stress intensities in the outer corrosion barrier. This calculation is intended for use in support of the preliminary design activities for the license applicationmore » design of the Naval waste package. It examines the effects of small changes between the naval canister and the inner vessel, and in these dimensions, the Naval Long waste package and Naval Short waste package are similar. Therefore, only the Naval Long waste package is used in this calculation and is based on the proposed potential designs presented by the drawings and sketches in References 2.1.10 to 2.1.17 and 2.1.20. All conclusions are valid for both the Naval Long and Naval Short waste packages.« less

Optical Reference Stars for Space Surveillance: Future Plans: Latest Developments

DTIC Science & Technology

2010-01-01

Micron All Sky Survey ( 2MASS ) has imaged the entire sky in near-infrared J(1.25m), H(1.65 m), and Ks(2.16 m) bandpasses from Mt Hopkins, Arizona...and Cerro Tololo, Chile. The 10-sigma detection levels reached 15.8, 15.1, and 14.3 mag at the J, H, and Ks bands, respectively. The 2MASS data...no proper motions for the stars. Information on 2MASS can be found at http://www.ipac.caltech.edu/ 2mass . UCAC The basis of the USNO CCD

VizieR Online Data Catalog: New PMS K/M Stars in Upper Scorpius (Rizzuto+, 2015)

NASA Astrophysics Data System (ADS)

Rizzuto, A. C.; Ireland, M. J.; Kraus, A. L.

2015-05-01

We have selected candidate Upper Scorpius members using kinematic and photometric data from UCAC4 (Zacharias et al., 2013, Cat. I/322), 2MASS (Skrutskie et al., 2006, Cat. VII/233), USNO-B (Monet et al. , 2003, Cat. I/284) and APASS (Henden et al., 2012, J. Am. Assoc. Var. Star Obs., 40, 430) We obtained 18 nights of time using WiFeS, split over 2013 and 2014; however, the majority of the 2013 nights were unusable due to weather. (3 data files).

Two-way time transfers between NRC/NBS and NRC/USNO via the Hermes (CTS) satellite

NASA Technical Reports Server (NTRS)

Costain, C. C.; Daams, H.; Boulanger, J. S.; Hanson, D. W.; Klepczynski, W. J.

1978-01-01

At each station the differences were measured between the local UTC seconds pulse and the remote UTC pulse received by satellite. The difference between the readings, if station delays are assumed to be symmetrical, is two times the difference between the clocks at the two ground station sites. Over a 20-minute period, the precision over the satellite is better than 1 ns. The time transfer from NRC to the CRC satellite terminal near Ottawa and from NBS to the Denver HEW terminal was examined.

Proceedings of the Nautical Almanac Office Sesquicentennial Symposium Held in Washington, The District of Columbia on March 3-4, 1999

DTIC Science & Technology

1999-03-01

Laboratory. While I was at USNO I was allocated a roll-top desk (previously used by H. R. Morgan) in the Library, and so I did not interact with the NAO...Tables de la lune construites d’apr~s le principe newtonien de la gravitation universelle would not be published until 1857. They were, on the other...the methodical calculations for the astronomical tables, Newcomb had much free time in his daily schedule of work. He allocated some of the hours to

78 FR 53109 - Security Zones; Naval Base Point Loma; Naval Mine Anti-Submarine Warfare Command; San Diego Bay...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-28

...-AA87 Security Zones; Naval Base Point Loma; Naval Mine Anti-Submarine Warfare Command; San Diego Bay... Anti-Submarine Warfare Command to protect the relocated marine mammal program. These security zone... Warfare Command, the Commander of Naval Region Southwest, or a designated representative of those...

33 CFR 165.1302 - Bangor Naval Submarine Base, Bangor, WA.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Bangor Naval Submarine Base... Bangor Naval Submarine Base, Bangor, WA. (a) Location. The following is a security zone: The waters of... States Naval vessels. (ii) Vessels that are performing work at Naval Submarine Base Bangor pursuant to a...

33 CFR 165.1302 - Bangor Naval Submarine Base, Bangor, WA.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Bangor Naval Submarine Base... Bangor Naval Submarine Base, Bangor, WA. (a) Location. The following is a security zone: The waters of... States Naval vessels. (ii) Vessels that are performing work at Naval Submarine Base Bangor pursuant to a...

33 CFR 165.1302 - Bangor Naval Submarine Base, Bangor, WA.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Bangor Naval Submarine Base... Bangor Naval Submarine Base, Bangor, WA. (a) Location. The following is a security zone: The waters of... States Naval vessels. (ii) Vessels that are performing work at Naval Submarine Base Bangor pursuant to a...

32 CFR 724.810 - Availability of Naval Discharge Review Board documents for public inspection and copying.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Availability of Naval Discharge Review Board... (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Procedures of Naval Discharge Review Board § 724.810 Availability of Naval Discharge Review Board documents for public inspection and...

33 CFR 334.1220 - Hood Canal, Bangor; naval restricted areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Hood Canal, Bangor; naval..., Bangor; naval restricted areas. (a) Hood Canal, Bangor; Naval restricted areas—(1) Area No. 1. That area...) Area No. 1. No person or vessel shall enter this area without permission from the Commander, Naval...

32 CFR 761.20 - Additional regulations governing persons and vessels in Naval Defensive Sea Areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... vessels in Naval Defensive Sea Areas. 761.20 Section 761.20 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION NAVAL DEFENSIVE SEA AREAS; NAVAL AIRSPACE... Instructions § 761.20 Additional regulations governing persons and vessels in Naval Defensive Sea Areas. (a) By...

7 CFR 160.203 - Fees for inspection and certification of other naval stores material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Fees for inspection and certification of other naval... AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES Specific Fees Payable for Services Rendered § 160.203 Fees for inspection and certification of other naval stores material. Whenever...

33 CFR 334.1220 - Hood Canal, Bangor; naval restricted areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Hood Canal, Bangor; naval..., Bangor; naval restricted areas. (a) Hood Canal, Bangor; Naval restricted areas—(1) Area No. 1. That area...) Area No. 1. No person or vessel shall enter this area without permission from the Commander, Naval...

32 CFR 724.810 - Availability of Naval Discharge Review Board documents for public inspection and copying.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Availability of Naval Discharge Review Board... (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Procedures of Naval Discharge Review Board § 724.810 Availability of Naval Discharge Review Board documents for public inspection and...

7 CFR 160.203 - Fees for inspection and certification of other naval stores material.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Fees for inspection and certification of other naval... AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES Specific Fees Payable for Services Rendered § 160.203 Fees for inspection and certification of other naval stores material. Whenever...

33 CFR 165.1302 - Bangor Naval Submarine Base, Bangor, WA.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Bangor Naval Submarine Base... Bangor Naval Submarine Base, Bangor, WA. (a) Location. The following is a security zone: The waters of... States Naval vessels. (ii) Vessels that are performing work at Naval Submarine Base Bangor pursuant to a...

View northeast; interior structural detail Naval Base PhiladelphiaPhiladelphia Naval ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View northeast; interior structural detail - Naval Base Philadelphia-Philadelphia Naval Shipyard, Foundry-Propeller Shop, North of Porter Avenue, west of Third Street West, Philadelphia, Philadelphia County, PA

Fringing in MonoCam Y4 filter images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brooks, J.; Fisher-Levine, M.; Nomerotski, A.

Here, we study the fringing patterns observed in MonoCam, a camera with a single Large Synoptic Survey Telescope (LSST) CCD sensor. Images were taken at the U.S. Naval Observatory in Flagstaff, Arizona (NOFS) employing its 1.3 m telescope and an LSST y4 filter. Fringing occurs due to the reflection of infrared light (700 nm or larger) from the bottom surface of the CCD which constructively or destructively interferes with the incident light to produce a net "fringe" pattern which is superimposed on all images taken. Emission lines from the atmosphere, dominated by hydroxyl (OH) spectra, can change in their relativemore » intensities as the night goes on, producing different fringe patterns in the images taken. We found through several methods that the general shape of the fringe patterns remained constant, though with slight changes in the amplitude and phase of the fringes. Lastly, we also found that a superposition of fringes from two monochromatic lines taken in the lab offered a reasonable description of the sky data.« less

The Speckle Toolbox: A Powerful Data Reduction Tool for CCD Astrometry

NASA Astrophysics Data System (ADS)

Harshaw, Richard; Rowe, David; Genet, Russell

2017-01-01

Recent advances in high-speed low-noise CCD and CMOS cameras, coupled with breakthroughs in data reduction software that runs on desktop PCs, has opened the domain of speckle interferometry and high-accuracy CCD measurements of double stars to amateurs, allowing them to do useful science of high quality. This paper describes how to use a speckle interferometry reduction program, the Speckle Tool Box (STB), to achieve this level of result. For over a year the author (Harshaw) has been using STB (and its predecessor, Plate Solve 3) to obtain measurements of double stars based on CCD camera technology for pairs that are either too wide (the stars not sharing the same isoplanatic patch, roughly 5 arc-seconds in diameter) or too faint to image in the coherence time required for speckle (usually under 40ms). This same approach - using speckle reduction software to measure CCD pairs with greater accuracy than possible with lucky imaging - has been used, it turns out, for several years by the U. S. Naval Observatory.

Fringing in MonoCam Y4 filter images

DOE PAGES

Brooks, J.; Fisher-Levine, M.; Nomerotski, A.

2017-05-05

Here, we study the fringing patterns observed in MonoCam, a camera with a single Large Synoptic Survey Telescope (LSST) CCD sensor. Images were taken at the U.S. Naval Observatory in Flagstaff, Arizona (NOFS) employing its 1.3 m telescope and an LSST y4 filter. Fringing occurs due to the reflection of infrared light (700 nm or larger) from the bottom surface of the CCD which constructively or destructively interferes with the incident light to produce a net "fringe" pattern which is superimposed on all images taken. Emission lines from the atmosphere, dominated by hydroxyl (OH) spectra, can change in their relativemore » intensities as the night goes on, producing different fringe patterns in the images taken. We found through several methods that the general shape of the fringe patterns remained constant, though with slight changes in the amplitude and phase of the fringes. Lastly, we also found that a superposition of fringes from two monochromatic lines taken in the lab offered a reasonable description of the sky data.« less

Morning twilight measured at Bandung and Jombang

NASA Astrophysics Data System (ADS)

Arumaningtyas, Eka Puspita; Raharto, Moedji; Herdiwijaya, Dhani

2012-06-01

Twilight divided into three categories namely, astronomical twilight, nautical twilight, and civil twilight. The three types of twilight can occur either in the evening or early morning. According to the U.S. Naval Observatory the three types distinguished by the depression (altitude of the sun below the horizon) for the evening or the morning twilight, -180, -120, and -60. Sky brightness measurements usually intended to determine the quality of the sky at some observation site or to determine the quality of the atmosphere by light pollution. Sky brightness data could be use for practical purposes such as to determine prayer times (Morning Prayer). This study describes the measurement of sky brightness using a light meter Sky Quality Meter. The measurements indicate the presence of different values and patterns in the twilight sky brightness. This variability highly determined by the weather conditions. Sky brightness shows a constant value shortly after the evening astronomical twilight and before morning astronomical twilight. Before the evening astronomical twilight and after morning astronomical twilight sky brightness showing continue changing.

33 CFR 334.260 - York River, Va.; naval restricted areas.

Code of Federal Regulations, 2012 CFR

2012-07-01

....; naval restricted areas. (a) The areas—(1) Naval mine service-testing area (prohibited). A rectangular... 76°31′50″ W.; and thence along the shore line to the point of beginning. (2) Naval mine service... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false York River, Va.; naval restricted...

33 CFR 334.260 - York River, Va.; naval restricted areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

....; naval restricted areas. (a) The areas—(1) Naval mine service-testing area (prohibited). A rectangular... 76°31′50″ W.; and thence along the shore line to the point of beginning. (2) Naval mine service... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false York River, Va.; naval restricted...

33 CFR 334.260 - York River, Va.; naval restricted areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

....; naval restricted areas. (a) The areas—(1) Naval mine service-testing area (prohibited). A rectangular... 76°31′50″ W.; and thence along the shore line to the point of beginning. (2) Naval mine service... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false York River, Va.; naval restricted...

7 CFR 160.201 - Fees generally for field inspection and certification of naval stores and drum containers of rosin.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of naval stores and drum containers of rosin. 160.201 Section 160.201 Agriculture Regulations of the... Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES... of naval stores and drum containers of rosin. Except as provided in § 160.204, the following fees...

32 CFR 700.333 - The Chief of Naval Research.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false The Chief of Naval Research. 700.333 Section 700... The Office of the Secretary of the Navy/the Staff Assistants § 700.333 The Chief of Naval Research. (a) The Chief of Naval Research shall command the Office of the Chief of Naval Research, the Office of...

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD...

33 CFR 334.1260 - Dabob Bay, Whitney Point; naval restricted area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Dabob Bay, Whitney Point; naval..., Whitney Point; naval restricted area. (a) Dabob Bay, Whitney Point, naval restricted area—(1) The area. Beginning at the high water line along the westerly shore of Dabob Bay, 100 yards northerly of the Naval...

33 CFR 334.775 - Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze, Fla.; naval restricted area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze, Fla.; naval restricted area. 334.775 Section 334.775 Navigation... RESTRICTED AREA REGULATIONS § 334.775 Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze...

77 FR 13296 - Subcommittee Meeting of the Board of Advisors to the President, Naval Postgraduate School

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-06

... President, Naval Postgraduate School AGENCY: Department of the Navy, DoD. ACTION: Notice of Open Meeting.... (Parent Committee is: Board of Advisors to the Presidents of the Naval Postgraduate School and the Naval... Time Zone. ADDRESSES: The meeting will be held at the Naval Postgraduate School, Herrmann Hall, 1...

33 CFR 334.1260 - Dabob Bay, Whitney Point; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Dabob Bay, Whitney Point; naval..., Whitney Point; naval restricted area. (a) Dabob Bay, Whitney Point, naval restricted area—(1) The area. Beginning at the high water line along the westerly shore of Dabob Bay, 100 yards northerly of the Naval...

33 CFR 334.775 - Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze, Fla.; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze, Fla.; naval restricted area. 334.775 Section 334.775 Navigation... RESTRICTED AREA REGULATIONS § 334.775 Naval Air Station Pensacola, Pensacola Bay, Pensacola and Gulf Breeze...

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD...

32 CFR 700.333 - The Chief of Naval Research.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false The Chief of Naval Research. 700.333 Section 700... The Office of the Secretary of the Navy/the Staff Assistants § 700.333 The Chief of Naval Research. (a) The Chief of Naval Research shall command the Office of the Chief of Naval Research, the Office of...

7 CFR 160.201 - Fees generally for field inspection and certification of naval stores and drum containers of rosin.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of naval stores and drum containers of rosin. 160.201 Section 160.201 Agriculture Regulations of the... Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) NAVAL STORES REGULATIONS AND STANDARDS FOR NAVAL STORES... of naval stores and drum containers of rosin. Except as provided in § 160.204, the following fees...

An Assessment of the Computer Science Activities of the Office of Naval Research

DTIC Science & Technology

1986-01-01

A Panel of the Naval Studies Board of the National Research Council met for two days in October 1985 to assess the computer science programs of the ... Office of Naval (ONR). These programs are supported by the Contract Research Program (CRP) as well as the Naval Research Laboratory (NRL), the Naval

Ghostly Glow Reveals a Hidden Class of Long-Wavelength Radio Emitters

NASA Astrophysics Data System (ADS)

2008-10-01

(Washington, DC. 08)- A team of scientists, including astronomers from the Naval Research Laboratory (NRL), have detected long wavelength radio emission from a colliding, massive galaxy cluster which, surprisingly, is not detected at the shorter wavelengths typically seen in these objects. The discovery implies that existing radio telescopes have missed a large population of these colliding objects. It also provides an important confirmation of the theoretical prediction that colliding galaxy clusters accelerate electrons and other particles to very high energies through the process of turbulent waves. The team revealed their findings in the October 16, 2008 edition of Nature. This new population of objects is most easily detected at long wavelengths. Professor Greg Taylor of the University of New Mexico and scientific director of the Long Wavelength Array (LWA) points out, "This result is just the tip of the iceberg. When an emerging suite of much more powerful low frequency telescopes, including the LWA in New Mexico, turn their views to the cosmos, the sky will 'light up' with hundreds or even thousands of colliding galaxy clusters." NRL has played a key role in promoting the development of this generation of new instruments and is currently involved with the development of the LWA. NRL radio astronomer and LWA Project Scientist Namir Kassim says "Our discovery of a previously hidden class of low frequency cluster-radio sources is particularly important since the study of galaxy clusters was a primary motivation for development of the LWA." The discovery of the emission in the galaxy cluster Abell 521 (or A521 for short) was made using the Giant Metrewave Radiotelescope (GMRT) in India, and its long wavelength nature was confirmed by the National Science Foundation's (NRAO) Very Large Array (VLA) radio telescope in New Mexico. The attached image shows the radio emission at a wavelength of 125cm in red superimposed on a blue image made from data taken by the Chandra X-ray Observatory. X-ray Chandra X-ray Image The X-ray emission comes from hot thermal gas, a well-known sign-post of massive galaxy clusters. Furthermore, its elongated shape indicates that the cluster has undergone a recent violent collision or "merger event" in which another group or cluster of galaxies was swallowed up by the gravitational potential of the main cluster. Interferometrics Inc. and NRL scientist Tracy Clarke, who is also the LWA System Scientist, notes "In addition to teaching us about the nature of Dark Matter, merging clusters are also important in studies of the mysterious nature of Dark Energy. Understanding these two strange components of the Universe will help us understand its ultimate destiny." In the radio image there is a strong, oblong source of emission located on the lower left periphery of the X-ray gas detected by Chandra; this is a separate source. In the center of the cluster, within the region indicated by a dashed circle, there is radio emission which changes significantly with wavelength. At the longest wavelength (125 cm, shown) it is clearly detected, but at a wavelength of 49 cm it is much fainter, and it is almost entirely gone at 21 cm wavelength. This multi-wavelength picture of the diffuse emission is in good agreement with theoretical predictions for particle acceleration by turbulent waves generated by a violent collision. People Who Read This Also Read... Black Holes Have Simple Feeding Habits NASA’s Swift Satellite Catches First Supernova in The Act of Exploding Oldest Known Objects Are Surprisingly Immature Chandra Data Reveal Rapidly Whirling Black Holes In a broader astrophysical context, galaxy clusters are the largest gravitationally bound systems in the Universe and their collisions are the most energetic events since the Big Bang. Says team leader Gianfranco Brunetti (Instituto di Radioastronomia, Bologna, Italy), "The A521 system provides evidence that turbulence acts as a source of particle acceleration in an environment that is unique in the Universe due to its large spatial and temporal scales, and due to the low density and high temperature of the gas." The team included scientists from Instituto di Radioastronomia, the University of Bologna, the Smithsonian Astrophysical Observatory, the National Radio Astronomy Observatory, and the Naval Research Laboratory. Basic research in radio astronomy at the Naval Research Laboratory is supported by 6.1 base funding. The NRAO is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. The LWA, funding for which is provided by the Office of Naval Research, is led by the University of New Mexico, and includes NRL, The Applied Research Laboratory at the University of Texas at Austin, Virginia Tech, the Los Alamos National Laboratory, and the University of Iowa, with contributions and cooperation from NRAO. The Long Wavelength Array (LWA) website is http://lwa.unm.edu The Naval Research Laboratory is the Department of the Navy's corporate laboratory. NRL conducts a broad program of scientific research, technology, and advanced development. The Laboratory, with a total complement of nearly 2,500 personnel, is located in southwest Washington, DC, with other major sites at the Stennis Space Center, MS; and Monterey, CA.

Naval Medical R and D News. March 2017, Volume 9, Issue 3

DTIC Science & Technology

2017-03-01

Medical Research Center (Feature) Military Medicine Provides World-Class Solutions for Combat Casualties From Naval Medical Research Center Public... Researchers from the Naval Surface Warfare Center Panama City Division and the Naval Postgraduate School spent the voyage conducting experiments to...interruptions, motion sickness incidence, and Sopite syndrome on surgical procedures while in a shipboard environment.... From Naval Medical Research

DoD-GEIS - DoD Global Emerging Infections Surveillance and Response System, Fiscal Year 2007

DTIC Science & Technology

2007-01-01

Weaver SC. Endemic eastern equine encephalitis in the Amazon Region of Peru . Am J Trop Med Hyg, 76:293-8, 2007. 3. Alibayeva G, Todd CS, Khakimov...Naval Medical Center Naval Health Research Center Naval Medical Research Center Naval Medical Research Center Detachment (Lima, Peru ) Naval Medical...Medical Research Center Detachment (Lima, Peru ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60

32 CFR 700.404 - Statutory authority and responsibility of the Office of the Chief of Naval Operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Office of the Chief of Naval Operations. 700.404 Section 700.404 National Defense Department of Defense... REGULATIONS AND OFFICIAL RECORDS The Chief of Naval Operations § 700.404 Statutory authority and responsibility of the Office of the Chief of Naval Operations. (a) The Office of the Chief of Naval Operations...

33 CFR 334.920 - Pacific Ocean off the east coast of San Clemente Island, Calif.; naval restricted area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... of San Clemente Island, Calif.; naval restricted area. 334.920 Section 334.920 Navigation and... RESTRICTED AREA REGULATIONS § 334.920 Pacific Ocean off the east coast of San Clemente Island, Calif.; naval... vessels, other than Naval Ordnance Test Station craft, and those cleared for entry by the Naval Ordnance...

LIADA's Double Star Section: Studies Of Visual Double Star By Amateurs

NASA Astrophysics Data System (ADS)

Rica, F. M.; Benavides, R.; Masa, E.; Ling, J.

2007-08-01

LIADA's Double Star Section has as main goal to perform measures of relative astrometry of neglected and unconfirmed wide pairs, as well as to determine the astrophysical properties for their components and classify them, according to their nature, as phyisical, common origin, common proper motion or optical pairs. BVIJHK photometry, relative astrometry and kinematical data in addition to other astrophysical parameters, were obtained from literature to characterize the components and the stellar systems. VizieR, Simbad. Aladin and the "services abstract" tools were used from the website of Centre De Données Stellaires de Strasbourg (CDS). USNO catalogs (USNO-B1.0 and UCAC-2) in addition to ESA catalogs (Tycho-2 and HIPPARCOS) were often used. Spectral types, luminosity classes, absolute magnitudes, photometric distances were determined by using several tables, two colours and reduced proper motion diagrams. Astrophysical properties were corrected by reddening by using several maps. CCD cameras, micrometric eyepieces, photographic plates from Digitalized Sky Survey (DSS) and other surveys were used to perform our astrometric measures. According to their nature double stars are classified by using several professional criteria. Since 2001 LIADA has studied about 500 visual double stars, has discovered about 150 true binaries and several candidates to be white dwarfs, subdwarfs and nearby stars. Several orbits have been calculated. Our results were published in national and international journals such as Journal of Double Star Observations (JDSO), in Information Circulars edited by Commision 26 of IAU and our measures were included in WDS catalog. LIADA publish a circular twice a year with our results.

Simulating Future GPS Clock Scenarios with Two Composite Clock Algorithms

NASA Technical Reports Server (NTRS)

Suess, Matthias; Matsakis, Demetrios; Greenhall, Charles A.

2010-01-01

Using the GPS Toolkit, the GPS constellation is simulated using 31 satellites (SV) and a ground network of 17 monitor stations (MS). At every 15-minutes measurement epoch, the monitor stations measure the time signals of all satellites above a parameterized elevation angle. Once a day, the satellite clock estimates the station and satellite clocks. The first composite clock (B) is based on the Brown algorithm, and is now used by GPS. The second one (G) is based on the Greenhall algorithm. The composite clock of G and B performance are investigated using three ground-clock models. Model C simulates the current GPS configuration, in which all stations are equipped with cesium clocks, except for masers at USNO and Alternate Master Clock (AMC) sites. Model M is an improved situation in which every station is equipped with active hydrogen masers. Finally, Models F and O are future scenarios in which the USNO and AMC stations are equipped with fountain clocks instead of masers. Model F is a rubidium fountain, while Model O is more precise but futuristic Optical Fountain. Each model is evaluated using three performance metrics. The timing-related user range error having all satellites available is the first performance index (PI1). The second performance index (PI2) relates to the stability of the broadcast GPS system time itself. The third performance index (PI3) evaluates the stability of the time scales computed by the two composite clocks. A distinction is made between the "Signal-in-Space" accuracy and that available through a GNSS receiver.

Implementation and Testing of the JANUS Standard with SSC Pacific’s Software-Defined Acoustic Modem

DTIC Science & Technology

2017-12-01

Communications Outpost (FDECO) Innovative Naval Prototype (INP) Program by the Advanced Photonic Technologies Branch (Code 55360), Space and Naval Warfare... Communications and Networks Division iii EXECUTIVE SUMMARY This report presents Space and Naval Warfare (SPAWAR) Systems Center Pacific’s (SSC... Frequency -Hopped Binary Frequency Shift Keying Office of Naval Research Innovative Naval Prototype Forward Deployed Energy and Communications Outpost

33 CFR 334.180 - Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Naval Mine Warfare Test Station, or of U.S. Naval Air Station property. A person in the water or a... areas, U.S. Naval Air Test Center, Patuxent River, Md. 334.180 Section 334.180 Navigation and Navigable... REGULATIONS § 334.180 Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md...

33 CFR 334.180 - Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Naval Mine Warfare Test Station, or of U.S. Naval Air Station property. A person in the water or a... areas, U.S. Naval Air Test Center, Patuxent River, Md. 334.180 Section 334.180 Navigation and Navigable... REGULATIONS § 334.180 Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md...

33 CFR 334.180 - Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Naval Mine Warfare Test Station, or of U.S. Naval Air Station property. A person in the water or a... areas, U.S. Naval Air Test Center, Patuxent River, Md. 334.180 Section 334.180 Navigation and Navigable... REGULATIONS § 334.180 Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md...

33 CFR 334.180 - Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Naval Mine Warfare Test Station, or of U.S. Naval Air Station property. A person in the water or a... areas, U.S. Naval Air Test Center, Patuxent River, Md. 334.180 Section 334.180 Navigation and Navigable... REGULATIONS § 334.180 Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md...

33 CFR 334.180 - Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Naval Mine Warfare Test Station, or of U.S. Naval Air Station property. A person in the water or a... areas, U.S. Naval Air Test Center, Patuxent River, Md. 334.180 Section 334.180 Navigation and Navigable... REGULATIONS § 334.180 Patuxent River, Md.; restricted areas, U.S. Naval Air Test Center, Patuxent River, Md...

VizieR Online Data Catalog: W1J00 and W2J00 Transit Circle Catalogs (Rafferty+, 2016)

NASA Astrophysics Data System (ADS)

Rafferty, T. J.; Holdenried, E. R.; Urban, S. E.

2016-06-01

The W1J00, named because it was the first (of two) Washington transit circle catalog to be referred to the Equinox of J2000.0, is the result of observations made with the Six-inch Transit Circle in Washington, D.C., between September 1977 and July 1982. The observing program was structured to be absolute, in the sense that the positions were not explicitly relying on any previous observations. The absolute positions were defined with respect to an internally consistent frame that was unique to the particular instrument. Following the reductions, comparisons with stars from the Hipparcos Catalogue (European Space Agency 1997) revealed unaccounted for systematic differences on the level of 100-200mas. It was decided, therefore, to include data on both the absolute positions reduced in way common to many past Washington transit circle catalogs, as well as the positions differentially adjusted to the system of the Hipparcos Catalog. The W1J00 contains mean positions of 7267 stars and 4383 observations of solar system objects. The majority of the stars fall into two categories; those from the Fifth Fundamental Catalog (FK5; Fricke et al 1988), and those from the Catalog Of 3539 Zodiacal Stars For The Equinox 1950.0 (Robertson 1940). The solar system objects include the Sun, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, eight minor planets (Eunomia, Flora, Hebe, Iris, Juno, Metis, Pallas, and Vesta), and the dwarf planet Ceres. Characteristics of the W1J00 catalog: Category Range Average ------------------------------------------------------------- Magnitudes -1.6 to 10.4 7.18 RA standard errors of the mean 15 to 460 mas 98 mas Dec standard errors of the mean 10 to 400 mas 107 mas RA Number of observations / star 3 to 187 10 Dec Number of observations / star 2 to 179 10 Declination coverage -39 to +90 degrees ------------------------------------------------------------- Details of the W1J00 can be found in Rafferty, Holdenried, and Urban (2016, Publ. USNO, 2nd series, vol. XXVII (part 1)). The W2J00 is the result of observations made with the Six-inch Transit Circle in Washington, D.C., and the Seven-inch Transit Circle at the Black Birch station near Blenheim, New Zealand. It is named as such because it was the second (of two) transit circle catalogs to be referred to the Equinox of J2000.0, and reduced at the Washington D.C. headquarters of the U.S. Naval Observatory. It is sometimes referred to as the "Pole-to-Pole" program due to the fact that the telescopes were situated at latitudes such that a fundamental determination could be made of the azimuth using circumpolar stars of both the northern and southern sky. The observations were made between April 1985 and February 1996. The W2J00 project is the latest and largest of a long series of transit circle catalogs produced by the U.S. Naval Observatory. It is also, because of advancing technologies, certainly the last. The observing program was structured to be absolute, in the sense that the reported positions were not to explicitly rely on previous observations. However, with the availability of Hipparcos observational data, it was decided to differentially adjust the observations to the ICRF using the Hipparcos star positions (ESA, 1997, Cat. I/239). A catalog on the ICRF was judged be more useful than one tied to the dynamical reference frame, as was the tradition. The W2J00 contains mean positions of 44,395 globally distributed stars, 5048 observations of the planets, and 6518 observations of the brighter minor planets. The majority of stars are FK stars (Fricke, et al., 1988, Cat. I/149 and 1991, Cat. I/175) and International Reference Stars (IRS) (Corbin, 1991, Cat. I/172). The solar system objects include Mars, Jupiter, Saturn, Uranus, Neptune, twelve minor planets (Amphitrite, Eunomia, Flora, Hebe, Hygiea, Iris, Juno, Melphomene, Metis, Nemausa, Pallas, and Vesta), and the dwarf planet Ceres. Daytime observations of the Sun, Mercury, Venus, Mars, and bright stars were made but not included in the final catalog due to the problems inherent in reducing observations made in the daylight. The W2J00 observing program used both the Six-inch Transit Circle and Seven-inch Transit Circle. Final positions are a combination of observations from both telescopes (for those stars in common). The authors have decided to present not only the combined positions, but the individual telescope's positions should future researchers decide to investigate the data based on which instrument was used. Characteristics of the W2J00 catalog: Category Range Average ------------------------------------------------------------- Magnitudes -1.6 to 9.91 6.84 RA standard errors of the mean 3 to 441 mas 68 mas Dec standard errors of the mean 1 to 448 mas 76 mas RA Number of observations / star 3 to 411 14 Dec Number of observations / star 2 to 418 14 Declination coverage -90 to +90 degrees ------------------------------------------------------------- Details of the W2J00 can be found in Holdenried and Rafferty (2016, PUSNO, 2nd series, vol. XXVII (part 2)). (4 data files).

32 CFR 770.31 - List of major naval installations in the State of Hawaii and cognizant commanders authorized to...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 96860. (2) Naval Western Oceanography Center, Pearl Harbor. Contact: Commanding Officer, Naval Western Oceanography Center, Box 113, Pearl Harbor, HI 96860. (3) Naval Air Station, Barbers Point. Contact: Commanding...

32 CFR 770.31 - List of major naval installations in the State of Hawaii and cognizant commanders authorized to...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 96860. (2) Naval Western Oceanography Center, Pearl Harbor. Contact: Commanding Officer, Naval Western Oceanography Center, Box 113, Pearl Harbor, HI 96860. (3) Naval Air Station, Barbers Point. Contact: Commanding...

32 CFR 770.31 - List of major naval installations in the State of Hawaii and cognizant commanders authorized to...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 96860. (2) Naval Western Oceanography Center, Pearl Harbor. Contact: Commanding Officer, Naval Western Oceanography Center, Box 113, Pearl Harbor, HI 96860. (3) Naval Air Station, Barbers Point. Contact: Commanding...

32 CFR 770.31 - List of major naval installations in the State of Hawaii and cognizant commanders authorized to...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 96860. (2) Naval Western Oceanography Center, Pearl Harbor. Contact: Commanding Officer, Naval Western Oceanography Center, Box 113, Pearl Harbor, HI 96860. (3) Naval Air Station, Barbers Point. Contact: Commanding...

32 CFR 770.31 - List of major naval installations in the State of Hawaii and cognizant commanders authorized to...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 96860. (2) Naval Western Oceanography Center, Pearl Harbor. Contact: Commanding Officer, Naval Western Oceanography Center, Box 113, Pearl Harbor, HI 96860. (3) Naval Air Station, Barbers Point. Contact: Commanding...

The United States Navy Arctic Roadmap for 2014 to 2030

DTIC Science & Technology

2014-02-01

of the Oceanographer of the Navy; the Chief of Naval Research; Commander, Naval Meteorology and Oceanography Command; Commander, Office of Naval...Q3, FY14 Q3, FY15 FY15-18 FY18 2.3.4: Improve traditional meteorological forecast capability in the polar regions through the...CNE Commander Naval Forces Europe CNIC Commander Navy Installations Command CNMOC Commander Naval Meteorology and Oceanography Command CNO Chief

Origin and evolution of US Naval strategic nuclear policy to 1960. Master's thesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kreitlein, H.C.

1986-12-01

This thesis treats the impact of the atomic bomb on traditional naval strategy as that strategy had developed under the influence of Captain Alfred T. Mahan, how traditional naval strategy was modified by the development of naval aviation, the lessons of World War II, and the leadership of James Forrestal, and how the adoption of atomic weapons into naval strategic planning was integrally tied to naval aviation. The growth of the Soviet Union as a threat to world peace, and interservice rivalry over roles and missions are compared as factors that influenced the development of post-World War II naval strategicmore » thinking. The Navy's reaction to the adoption of massive retaliation as the foundation of the national strategic nuclear policy is discussed and analyzed.« less

Organizing OPNAV (1970-2009). Revision 2

DTIC Science & Technology

2010-01-01

Naval Operations, (N4) Deputy Chief of Naval Operations, (N8) Director, Navy Staff Commander, Fleet Forces Command President , Naval War College... President , Naval Postgraduate School Subj: STUDY "ORGANIZING OPNAV, 1970-2009" Encl: (1) copy "Organizing OPNAV, 1970-2009" 1. The Naval History and...office. Completion of this study is timed to coincide with the upcoming 100th anniversary of the 1915 creation of the position of CNO by President

Pluto's Atmosphere from the July 2010 Stellar Occultation

NASA Astrophysics Data System (ADS)

Person, Michael J.; Elliot, J. L.; Bosh, A. S.; Gulbis, A. A. S.; Jensen-Clem, R.; Lockhart, M. F.; Zangari, A. M.; Zuluaga, C. A.; Levine, S. E.; Pasachoff, J. M.; Souza, S. P.; Lu, M.; Malamut, C.; Rojo, P.; Bailyn, C. D.; MacDonald, R. K. D.; Ivarsen, K. M.; Reichart, D. E.; LaCluyze, A. P.; Nysewander, M. C.; Haislip, J. B.

2010-10-01

We have observed the 4 July 2010 stellar occultation by Pluto as part of our program of monitoring Pluto's atmospheric changes over the last decade. Successful observations were obtained from three sites: Cerro Calan and Cerro Tololo, Chile, as well as the HESS-project site (High Energy Stereoscopic System) in southwestern Namibia. Successful telescope apertures ranged from 0.45 m to 1.0 m and resulted in seven occultation light curves for the event from among the three sites. Simultaneous analysis of the seven light curves indicates that Pluto's atmosphere continues to be stable, as the calculated atmospheric radii are consistent with those detected in 2006 (Elliot et al., AJ 134, 1, 2007) and 2007 (Person et al., AJ 136, 1510, 2008), continuing the stability that followed the large pressure increase detected between 1988 (Millis et al., Icarus 105, 282, 1993) and 2002 (Elliot et al., Nature 424, 165, 2003). We will present the overall astrometric solution as well as current profiles for Pluto's upper atmospheric temperature and pressure obtained from inversion of the light curves (Elliot, Person, and Qu, AJ 126, 1041, 2003). This work was supported, in part, by grants NNX10AB27G to MIT, NNX08AO50G to Williams College, and NNH08AI17I to the USNO from NASA's Planetary Astronomy Division. The 0.75-m ATOM (Automatic Telescope for Optical Monitoring) light curve was obtained with the generous assistance of the HESS-project staff, arranged by Stefan Wagner and Marcus Hauser of the University of Heidelberg. The 0.45-m Goto telescope at Cerro Calán National Astronomical Observatory, Universidad de Chile, was donated by the Government of Japan. PROMPT (Panchromatic Robotic Optical Monitoring and Polarimetry Telescopes) observations at Cerro Tololo were made possible by the Robert Martin Ayers Science Fund. Student participation was supported in part by NSF's REU program and NASA's Massachusetts Space Grant.

DESIGN ANALYSIS FOR THE NAVAL SNF WASTE PACKAGE

DOE Office of Scientific and Technical Information (OSTI.GOV)

T.L. Mitchell

2000-05-31

The purpose of this analysis is to demonstrate the design of the naval spent nuclear fuel (SNF) waste package (WP) using the Waste Package Department's (WPD) design methodologies and processes described in the ''Waste Package Design Methodology Report'' (CRWMS M&O [Civilian Radioactive Waste Management System Management and Operating Contractor] 2000b). The calculations that support the design of the naval SNF WP will be discussed; however, only a sub-set of such analyses will be presented and shall be limited to those identified in the ''Waste Package Design Sensitivity Report'' (CRWMS M&O 2000c). The objective of this analysis is to describe themore » naval SNF WP design method and to show that the design of the naval SNF WP complies with the ''Naval Spent Nuclear Fuel Disposal Container System Description Document'' (CRWMS M&O 1999a) and Interface Control Document (ICD) criteria for Site Recommendation. Additional criteria for the design of the naval SNF WP have been outlined in Section 6.2 of the ''Waste Package Design Sensitivity Report'' (CRWMS M&O 2000c). The scope of this analysis is restricted to the design of the naval long WP containing one naval long SNF canister. This WP is representative of the WPs that will contain both naval short SNF and naval long SNF canisters. The following items are included in the scope of this analysis: (1) Providing a general description of the applicable design criteria; (2) Describing the design methodology to be used; (3) Presenting the design of the naval SNF waste package; and (4) Showing compliance with all applicable design criteria. The intended use of this analysis is to support Site Recommendation reports and assist in the development of WPD drawings. Activities described in this analysis were conducted in accordance with the technical product development plan (TPDP) ''Design Analysis for the Naval SNF Waste Package (CRWMS M&O 2000a).« less

75 FR 6642 - Notice of Proposed Information Collection; Naval Special Warfare Recruiting Directorate

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

... Information Collection; Naval Special Warfare Recruiting Directorate AGENCY: Department of the Navy, DoD. ACTION: Notice. SUMMARY: The Naval Special Warfare (NSW) Recruiting Directorate announces the submission... the proposal and associated collection instruments, write to the Director, Naval Special Warfare...

Calculation of the Naval Long and Short Waste Package Three-Dimensional Thermal Interface Temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

H. Marr

2006-10-25

The purpose of this calculation is to evaluate the thermal performance of the Naval Long and Naval Short spent nuclear fuel (SNF) waste packages (WP) in the repository emplacement drift. The scope of this calculation is limited to the determination of the temperature profiles upon the surfaces of the Naval Long and Short SNF waste package for up to 10,000 years of emplacement. The temperatures on the top of the outside surface of the naval canister are the thermal interfaces for the Naval Nuclear Propulsion Program (NNPP). The results of this calculation are intended to support Licensing Application design activities.

32 CFR 724.406 - Commander, Naval Medical Command.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Commander, Naval Medical Command. 724.406 Section 724.406 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Medical Command. Custodian of Navy and Marine Corps health records. (See subpart C). ...

32 CFR 724.406 - Commander, Naval Medical Command.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Commander, Naval Medical Command. 724.406 Section 724.406 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Medical Command. Custodian of Navy and Marine Corps health records. (See subpart C). ...

32 CFR 724.406 - Commander, Naval Medical Command.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Commander, Naval Medical Command. 724.406 Section 724.406 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Medical Command. Custodian of Navy and Marine Corps health records. (See subpart C). ...

32 CFR 724.406 - Commander, Naval Medical Command.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Commander, Naval Medical Command. 724.406 Section 724.406 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Medical Command. Custodian of Navy and Marine Corps health records. (See subpart C). ...

32 CFR 724.406 - Commander, Naval Medical Command.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Commander, Naval Medical Command. 724.406 Section 724.406 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Medical Command. Custodian of Navy and Marine Corps health records. (See subpart C). ...

POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - UNITED STATES NAVAL BASE NORFOLK NAVAL AIR STATION

EPA Science Inventory

This report summarizes work conducted at the U.S. Navy's Naval Base Norfolk, Naval Air Station (NAS) located at Sewells Point in Norfolk, Virginia, under the U.S. Environmental Protection Agency's (EPA) Waste Reduction Evaluations at Federal Sites (WREAFS) Program. This project w...

77 FR 39490 - Meeting of the Naval Research Advisory Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-03

... DEPARTMENT OF DEFENSE Department of the Navy Meeting of the Naval Research Advisory Committee... Naval Research Advisory Committee (NRAC) will meet August 20 through August 24 and August 27 through... INFORMATION CONTACT: Mr. William H. Ellis, Jr., Program Director, Naval Research Advisory Committee, 875 North...

21. Scrapping In Dry Dock #4. Naval Shipyard Philadelphia. February ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. Scrapping In Dry Dock #4. Naval Shipyard Philadelphia. February 18, 1946. Original Photograph In Collection of National Archives, Mid-Atlantic Regional Records Center, Philadelphia. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Dry Dock No. 4, Broad Street south of Government Avenue, Philadelphia, Philadelphia County, PA

32 CFR 724.102 - Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Naval Discharge Review Board. 724.102 Section 724.102 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.102 Naval Discharge Review Board. An administrative board, referred...

32 CFR 724.102 - Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Naval Discharge Review Board. 724.102 Section 724.102 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.102 Naval Discharge Review Board. An administrative board, referred...

Old Books Bring New Life to the Brick and Mortar Library

NASA Astrophysics Data System (ADS)

Bosken, S.

2012-08-01

If all the library books and journals can be viewed on your desk top, why come to the physical library? The USNO Library tried to bring the patrons inside the library. One method was to rotate rare book displays each month. As the library holds a fabulous collection of ancient astronomy books, including Copernicus, Kepler, Galileo, and Newton, we have abundant resources. The presentation will highlight the varied displays and offer a Rare Books 101 explanation of paper, printing, binding and a behind-the-scenes look at how old books are maintained and preserved.

Optical flare of an X-ray source XMMSL1 J014956.7+533504

NASA Astrophysics Data System (ADS)

Korotkiy, S. A.; Sokolovsky, K. V.

2012-01-01

A bright (unfiltered magnitude 12.8) optical flare was detected on 2012 January 29 at position 01:49:56.77 +53:35:01.8 (+/-0.5", J2000) coinciding with an X-ray source listed in the XMM-Newton slew survey catalog XMMSL1 J014956.7+533504 (Saxton et al. 2008, A&A, 480, 611), an optical object USNO-B1.0 1435-0053799 (B1mag=15.96, R1mag=14.86; Monet et al. 2003, AJ, 125, 984), and a near-infrared object 2MASS 01495682+5335017.

Characterization of the Praesepe Star Cluster by Photometry and Proper Motions With 2MASS, PPMXL, and Pan-STARRS

DTIC Science & Technology

2014-03-20

reserved. Printed in the U.S.A. CHARACTERIZATION OF THE PRAESEPE STAR CLUSTER BY PHOTOMETRY AND PROPER MOTIONS WITH 2MASS , PPMXL, AND Pan-STARRS P. F. Wang1... 2MASS ) and the Sloan Digital Sky Survey (SDSS) data, covering a sky area of 100 deg2, Adams et al. (2002) extended the lower main sequence to 0.1M, and...incompleteness is caused by the detection limits of USNO-B1 and 2MASS . Recently, Khalaj & Baumgardt (2013) used SDSS and PPMXL data to characterize

HUBBLE'S PLANETARY NEBULA GALLERY

NASA Technical Reports Server (NTRS)

2002-01-01

[Top left] - IC 3568 lies in the constellation Camelopardalis at a distance of about 9,000 light-years, and has a diameter of about 0.4 light-years (or about 800 times the diameter of our solar system). It is an example of a round planetary nebula. Note the bright inner shell and fainter, smooth, circular outer envelope. Credits: Howard Bond (Space Telescope Science Institute), Robin Ciardullo (Pennsylvania State University) and NASA [Top center] - NGC 6826's eye-like appearance is marred by two sets of blood-red 'fliers' that lie horizontally across the image. The surrounding faint green 'white' of the eye is believed to be gas that made up almost half of the star's mass for most of its life. The hot remnant star (in the center of the green oval) drives a fast wind into older material, forming a hot interior bubble which pushes the older gas ahead of it to form a bright rim. (The star is one of the brightest stars in any planetary.) NGC 6826 is 2,200 light- years away in the constellation Cygnus. The Hubble telescope observation was taken Jan. 27, 1996 with the Wide Field and Planetary Camera 2. Credits: Bruce Balick (University of Washington), Jason Alexander (University of Washington), Arsen Hajian (U.S. Naval Observatory), Yervant Terzian (Cornell University), Mario Perinotto (University of Florence, Italy), Patrizio Patriarchi (Arcetri Observatory, Italy) and NASA [Top right ] - NGC 3918 is in the constellation Centaurus and is about 3,000 light-years from us. Its diameter is about 0.3 light-year. It shows a roughly spherical outer envelope but an elongated inner balloon inflated by a fast wind from the hot central star, which is starting to break out of the spherical envelope at the top and bottom of the image. Credits: Howard Bond (Space Telescope Science Institute), Robin Ciardullo (Pennsylvania State University) and NASA [Bottom left] - Hubble 5 is a striking example of a 'butterfly' or bipolar (two-lobed) nebula. The heat generated by fast winds causes each of the lobes to expand, much like a pair of balloons with internal heaters. This observation was taken Sept. 9, 1997 by the Hubble telescope's Wide Field and Planetary Camera 2. Hubble 5 is 2,200 light-years away in the constellation Sagittarius. Credits: Bruce Balick (University of Washington), Vincent Icke (Leiden University, The Netherlands), Garrelt Mellema (Stockholm University), and NASA [Bottom center ] - Like NGC 6826, NGC 7009 has a bright central star at the center of a dark cavity bounded by a football-shaped rim of dense, blue and red gas. The cavity and its rim are trapped inside smoothly-distributed greenish material in the shape of a barrel and comprised of the star's former outer layers. At larger distances, and lying along the long axis of the nebula, a pair of red 'ansae', or 'handles' appears. Each ansa is joined to the tips of the cavity by a long greenish jet of material. The handles are clouds of low-density gas. NGC 7009 is 1,400 light-years away in the constellation Aquarius. The Hubble telescope observation was taken April 28, 1996 by the Wide Field and Planetary Camera 2. Credits: Bruce Balick (University of Washington), Jason Alexander (University of Washington), Arsen Hajian (U.S. Naval Observatory), Yervant Terzian (Cornell University), Mario Perinotto (University of Florence, Italy), Patrizio Patriarchi (Arcetri Observatory, Italy), NASA [Bottom right ] - NGC 5307 also lies in Centaurus but is about 10,000 light-years away and has a diameter of approximately 0.6 light-year. It is an example of a planetary nebula with a pinwheel or spiral structure; each blob of gas ejected from the central star has a counterpart on the opposite side of the star. Credits: Howard Bond (Space Telescope Science Institute), Robin Ciardullo (Pennsylvania State University) and NASA

33 CFR 334.815 - Menominee River, at the Marinette Marine Corporation Shipyard, Marinette, Wisconsin; naval...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Marine Corporation Shipyard, Marinette, Wisconsin; naval restricted area. 334.815 Section 334.815... Shipyard, Marinette, Wisconsin; naval restricted area. (a) The area. The waters adjacent to Marinette... local military or Naval authority, vessels of the United States Coast Guard, and local or state law...

33 CFR 334.815 - Menominee River, at the Marinette Marine Corporation Shipyard, Marinette, Wisconsin; naval...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Marine Corporation Shipyard, Marinette, Wisconsin; naval restricted area. 334.815 Section 334.815... Shipyard, Marinette, Wisconsin; naval restricted area. (a) The area. The waters adjacent to Marinette... local military or Naval authority, vessels of the United States Coast Guard, and local or state law...

33 CFR 334.815 - Menominee River, at the Marinette Marine Corporation Shipyard, Marinette, Wisconsin; naval...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Marine Corporation Shipyard, Marinette, Wisconsin; naval restricted area. 334.815 Section 334.815... Shipyard, Marinette, Wisconsin; naval restricted area. (a) The area. The waters adjacent to Marinette... local military or Naval authority, vessels of the United States Coast Guard, and local or state law...

32 CFR 728.76 - Naval Home residents.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Naval Home residents. 728.76 Section 728.76... FOR ELIGIBLE PERSONS AT NAVY MEDICAL DEPARTMENT FACILITIES Other Persons § 728.76 Naval Home residents. Provide necessary medical and dental care, both inpatient and outpatient, to residents of the Naval Home...

78 FR 58524 - Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training and Testing...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-24

... and testing activities: anti-surface warfare; anti- submarine warfare; mine warfare; naval special warfare; major training activities; Naval Air Systems Command (NAVAIR) testing; anti-surface warfare testing; anti-submarine warfare testing; Naval Sea Systems Command (NAVSEA) testing; and Office of Naval...