Swinburne University of Technology | 2017 Apr 06
An international team of astronomers has, for the first time, spotted a massive, inactive galaxy from a time when the Universe was only 1.65 billion years old.
Astronomers expect most galaxies from this epoch to be low-mass minnows, busily forming stars. However, this galaxy is ‘a monster’ and inactive, according to Professor Karl Glazebrook, Director of Swinburne’s Centre for Astrophysics and Supercomputing, who led the team.
The researchers found that within a short time period this massive galaxy, known as ZF-COSMOS-20115, formed all its stars (three times more than our Milky Way today) through an extreme star-burst event. But it stopped forming stars only a billion years after the Big Bang to become a quiescent or ‘red and dead’ galaxy -- common in our universe today, but not expected to exist at this ancient epoch.
The galaxy is also small and extremely dense: it has 300 billion stars crammed into a region of space about the same size as the distance from the Sun to the nearby Orion Nebula. ...
A massive, quiescent galaxy at redshift of z=3.717 - Karl Glazebrook et al