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Stars: demographic decrease

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An international team of astronomers, whilst reconstructing how the pace of the formation of new stars has changed throughout the history of the Universe, discovered that we presently find ourselves faced with a genuine demographic decrease.

Extracting the data gathered using the UKIRT, VLT and Subaru telescopes, David Sobral (Leiden University) and colleagues discovered that half of the stars which are currently present in the Universe, were developed between 9 and 11 billion years ago. Following the birth boom, the demographic growth became increasingly slower: 9 billion years were needed to create the second half of the present stars. According to the researchers, who had access to ten times more data than that available up to the present, with which to conduct the same analysis, the current rate of stellar creation has reduced 30 times when compared to the maximum value.

In addition to the fact that this may concern us directly, the future of the Universe has never looked so gloomy. In the study, which will appear in the next edition of Monthly Notices of the Royal Astronomical Society, it has been suggested that, at this rate, only a further 5% of new stars will be created in the Universe. "We are living in a Universe of old stars - highlights Sobral - and we cannot ignore the fact that our Galaxy is still quite active in terms of stellar creation".

Royal Astronomical Society - Research paper

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