Baptised MSSS (which stands for Multi-frequency Snapshot Sky Survey), this survey has yielded a first series of images, the analysis of which has shown up a new source whose apparent size is that of the full Moon. The new object falls in the class of « Giant Radio Galaxies » (GRGs) whose principal characteristic is their very large size
The radio emission is associated with matter ejected by a super-massive black hole situated in the center of a galaxy, itself interacting with about ten other galaxies. The central galaxy is at a redshift de of z=0.054536, i.e. roughly 750 million light years from the Earth.
This is a remarkable discovery, since this radio-galaxy, whose size is that of an entire cluster of galalxies, is not visible in any of the surveys made at higher frequencies, notably using the Very Large Array (VLA – U.S.A.) interferometer.
The imaging system which enabled this image to be obtained is equivalent to digital adaptive optics, and was almost entirely developed at theObservatoire de Paris. Note that many of the instrumental and digital techniques which were developed for LOFAR, such as this imager, will be used in the implementation of upcoming radio-telescope projects such as the Square Kilometre Array (SKA).
French Participation in LOFAR
LOFAR is managed by ASTRON, the Dutch radio-astronomical institute, for a consortium composed of the Netherlands, Germany, the United Kingdom, Sweden and France. The Observatoire de Paris, the Observatoire de la Côte d’Azur, the LPC2E in Orléans, are directly involved in the use and the development of LOFAR and of the precursors to SKA.
In particular, the scientific departments Galaxies, Etoiles, Physique et Instrumentation - GEPI and the Laboratoire d’Etudes Spatiales et d’Instrumentation en astrophysique - LESIA - of the Observatoire de Paris, as well as its Nançay radio-astronomical observatory, are involved in the scientific use of LOFAR (extragalactic surveys, , transient phenomena in the Universe), as is the laboratoire Lagrange of the Observatoire de la Côte d’Azur.