A cloud of expanding gas in space is the largest supernova remnant ever seen in the sky, a new study confirms.
The Milky Way has some 300 known supernova remnants, each made of debris from an exploded star mixed with interstellar material swept up by the blast. This supersized one, located in the constellation Antlia, isn’t necessarily the biggest of all physically, but thanks to its proximity to us, it
looks the biggest. As seen from Earth, it
spans a region of sky more than 40 times the size of a full moon, astronomer Robert Fesen of Dartmouth College and his colleagues report February 25 at arXiv.org. The Antlia remnant appears about three times as large as the previous champion, the
Vela supernova remnant (
SN: 7/8/20).
The star that created the Antlia supernova remnant exploded roughly 100,000 years ago. Estimates of the remnant’s distance vary, so its physical size has yet to be nailed down. But if the cloud is 1,000 light-years away, then it’s about 390 light-years across; if it’s twice as far, then it’s twice as big. Either way, it’s considerably larger than the Vela supernova remnant, which is about 100 light-years wide.
www.sciencenews.org