The Universe is running out of gas and forming fewer stars than it used too.
ScienceDaily — A CSIRO study has shown why the lights are going out in the Universe. The Universe forms fewer stars than it used to, and a CSIRO study has now shown why: the galaxies are running out of gas.
Dr Robert Braun (CSIRO Astronomy and Space Science) and his colleagues used CSIRO's Mopra radio telescope near Coonabarabran, NSW, to study far-off galaxies and compare them with nearby ones.
Light (and radio waves) from the distant galaxies has taken time to travel to us, so we see the galaxies as they were between three and five billion years ago.
Galaxies at this stage of the Universe's life appear to contain considerably more molecular hydrogen gas than comparable galaxies in today's Universe, the research team found.
Stars form from clouds of molecular hydrogen. The less molecular hydrogen there is, the fewer stars will form.
The research team's paper is in press in Monthly Notices of the Royal Astronomical Society.