A galaxy is born: This artist's impression shows a young galaxy, about two billion years after the Big Bang, accreting material from the surrounding hydrogen and helium gas and forming many young stars. (Image credit: ESO)
Galaxies, distant from us in space and time, have been in the news recently. Astronomers knew that far away galaxies (and hence ancient galaxies)were smaller than those galaxies closer (in time and space) to us today in the Milky Way. It was believed that the first galaxies appeared less than a billion year after the Big Bang and as time passed the galaxies grew, enlarging themselves as they collided with and absorbed smaller galaxies.
Astronomers at the European Southern Observatory have observed another process which helped primordial galaxies grow. This is a very important discovery; the textbooks are going to have to be rewritten. The European astronomers’ research has shown€а young galaxies formed stars by directly sucking in streams of the cool hydrogen and helium gas that filled the early Universe. Deep inside these early stars nuclear fusion created all the heavy elements which later were distributed by supernovae, eventually going to make up planets and even you and me.
There's no such place as far away (Image credit: HST via ESO)
The astronomers at ESO have also verified an important Hubble Space Telescope discovery. The dim little speck highlighted in the image above is a little galaxy of only a billion or so stars somewhere in Fornax (the constellation of the Furnace). Called UDFy-38135539, this galaxy is significant because it is the most distant object we have discovered to date. The light from it has travelled at least€а 13.1 billion years to get to Earth and we are seeing as it was only 500-600 million years after the Big Bang.
It is marvellous to live in these times when we are finding just how vast and ancient our cosmos is!
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