The giant arc was first recognized by the French group in September 1985, on direct images of Abell 370, obtained with the French-Canadian 3.6 m telescope on Mauna Kea, Hawaii. This exciting discovery opens an entirely new field of observational astronomy. It is caused by the deflection of light from a background galaxy by the dense core of the cluster Abell 370. They were able to show that the object is a “gravitational ring", a phenomenon predicted by Einstein, but never observed before. Several atomic spectral lines have been unambiguously identified in the arc by a group of astronomers from the Toulouse Observatory, France. The combination of a very dark sky at the ESO La Silla observatory, the large collecting area of the 3.6 m telescope and the high efficiency of the ESO Faint Object Spectrograph (EFOSC) has made it possible to obtain for the first time a convincing spectrum that reveals the true nature of a mysterious object, the prototype “Giant Luminous Arc" in the distant cluster of galaxies Abell 370. Studies of other objects of the same type will open entirely new vistas in the exploration of the nature of distant galaxies. The prototype of a new class of astrophysical phenomena has now been interpreted.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |