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The Complete Star Formation History of the Universe

Alan Heavens·Benjamin Panter·Raul Jimenez·James Dunlop
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Abstract

The determination of the star-formation history of the Universe is a key goal of modern cosmology, as it is crucial to our understanding of how structure in the Universe forms and evolves. A picture has built up over recent years, piece-by-piece, by observing young stars in distant galaxies at different times in the past. These studies indicated that the stellar birthrate peaked some 8 billion years ago, and then declined by a factor of around ten to its present value. Here we report on a new study which obtains the complete star formation history by analysing the fossil record of the stellar populations of 96545 nearby galaxies. Broadly, our results support those derived from high-redshift galaxies elsewhere in the Universe. We find, however, that the peak of star formation was more recent - around 5 billion years ago. Our study also shows that the bigger the stellar mass of the galaxy, the earlier the stars were formed. This striking result indicates a very different formation history for high- and low-mass formation.

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Alan Heavens, Benjamin Panter, Raul Jimenez, James Dunlop. 2004-03-11. The Complete Star Formation History of the Universe. https://doi.org/10.1038/nature02474

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