The Most Distant Quasars and the First Super-Massive Black Holes

Synopsis:

At the centre of every large galaxy there is a super-massive black hole, with a mass up to a billion times that of the sun.  These incredible objects grow by accreting material which is heated to temperatures of tens of thousands of degrees, giving off more light than the surrounding galaxy of stars - this is what we see as a quasar.  Quasars are so luminous that they can be detected at great distances and hence seen as they were billions of years in the past, when the Universe was just ~5% of its current age (of 13.8 billion years).  Unfortunately, such early quasars are also very rare, with just a few hundred dotted across the entire sky.  This talk will describe how astronomers search for the most distant quasars, with a particular focus on recent discoveries from the Euclid space telescope, as well as examining the implications for…