In the 23 September 1991 episode, Patrick looked at the exciting discovery of what appeared to be the most luminous object ever seen, that hadjust been found by the Infrared Astronomical Satellite (IRAS).
During a survey to measure the redshifts of 1,400 galaxies, the team found one, IRAS F10214+4724, appeared to be considerably further away than expected. Its light had set out when the Universe wasjust 80 per cent its current age and had travelled 16 billion lightyearsto reach Earth. At that distance, the galaxy would be brighter than 30 trillion Suns or 30,000 times that of the entire Milky Way.
Yet despite being so luminous it was also practically invisible, as 99 per cent of its lightmore massive than all the heavy elements of the Milky Way put together.
