‘Cosmic GDP’ Crashes 97% As Star Formation Slumps

While parts of the world experience economic hardship, a team of Portuguese, UK, Japanese, Italian and Dutch astronomers has found an even bigger slump happening on a cosmic scale. In the largest ever study of its kind, the international team of astronomers has established that the rate of formation of new stars in the Universe is now only 1/30th of its peak and that this decline is only set to continue. The team, led by David Sobral of the University of Leiden in the Netherlands, publish their results in the journal Monthly Notices of the Royal Astronomical Society.

The accepted model for the evolution of the Universe suggests that stars began to form about 13.4 billion years ago, or around three hundred million years after the Big Bang. Many of these first stars are thought to have been monsters by today’s standards, and were probably hundreds of times more massive than our Sun. Such beasts aged very quickly, exhausted their fuel, and exploded as supernovae within a million years or so. Lower mass stars in contrast have much longer lives and last for billions of years.

In the new study, scientists used the UK Infrared Telescope (UKIRT), the Very Large Telescope (VLT) and the Subaru telescope to carry out the most complete survey ever made of star-forming galaxies at different distances, with around ten times the data of any previous effort. With the range of distances, the time taken for the light to reach us means that we see identically selected galaxies at different periods in the history of the universe, so we can really understand how conditions change over time.

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