Nearest Cosmic Mirage

NASA Astrophysics Data System (ADS)

2003-07-01

will use new observations which are currently being obtained with the VLT at Paranal, with the VLA radio interferometer in New Mexico and with the Hubble Space Telescope. More information The research described in this press release is presented in a Letter to the Editor, soon to appear in the European professional journal Astronomy & Astrophysics ("A quadruply imaged quasar with an optical Einstein ring candidate : 1RXS J113155.4-123155", by Dominique Sluse et al.). More information on gravitational lensing and on this research group can also be found at the URL : http://www.astro.ulg.ac.be/GRech/AEOS/. Notes [1]: The team consists of Dominique Sluse, Damien Hutsemékers, and Thodori Nakos (ESO and Institut d'Astrophysique et de Géophysique de l'Université de Liège - IAGL), Jean-François Claeskens, Frédéric Courbin, Christophe Jean, and Jean Surdej (IAGL), Malvina Billeres (ESO), and Sergiy Khmil (Astronomical Observatory of Shevchentko University). [2]: Quasars are particularly active galaxies, the centres of which emit prodigious amounts of energy and energetic particles. It is believed that they harbour a massive black hole at their centre and that the energy is produced when surrounding matter falls into this black hole. This type of object was first discovered in 1963 by the Dutch-American astronomer Maarten Schmidt at the Palomar Observatory (California, USA) and the name refers to their "star-like" appearance on the images obtained at that time. [3]: In astronomy, the "redshift" denotes the fraction by which the lines in the spectrum of an object are shifted towards longer wavelengths. Since the redshift of a cosmological object increases with distance, the observed redshift of a remote galaxy also provides an estimate of its distance.