
What is the smallest known star in the Universe?
Just big enough to be a star but a barely functioning one.
Asked by: Bob, via sciencefocus.com
In 2017, an international team of astronomers announced the discovery of a so-called red dwarf star that’s so small it barely functions as a star. Code-named EBLM J0555-57Ab and lying some 600 light-years away, it’s similar in size to the planet Saturn. It has just enough mass to maintain the conditions needed to fuse together nuclei of hydrogen – the power source of stars like the Sun. Any smaller, and it would have become a brown dwarf – a ‘failed star’.

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Authors

Robert is a science writer and visiting professor of science at Aston University.
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