Lighthouses at the Edge of the Universe
Friday 24th May 2013
Physics Lecture Theatre, Old Main Building, UNSW Kensington Campus
Speaker: Dr. Rajan chhetri
In March 1963, three articles in the magazine Nature discussed the discovery of a "star-like" object at the redshift of 0.158 (corresponding to a distance of more than 2 billion light years away from us - one of the most distant objects then discovered). In the fifty years since this discovery, similar but even more distant objects have been discovered. They have been given various names - quasi stellar objects, QSOs, quasars and active galactic nuclei (AGNs). These objects are now known to be associated with supermassive black holes at the centres of galaxies. It is understood that active regions similar in size to our solar system produce tremendous amounts of energy; thousands of times as much as from the rest of the galaxy combined. These highly energetic objects from distant parts of the Universe, and the distant past, act as beacons helping us to better understand the Universe. I will give a brief account of the part played by Australia's Parkes telescope in their discovery and discuss some of their extraordinary properties.