supernova
noun
Did you know?
A nova, despite its name, isn't actually a "new" star, but rather one that wasn't noticed until it exploded, when it may increase in brightness by a million times before returning to its previous state a few days later. A supernova is far larger; a star in its supernova state may emit a billion times as much light as previously. After a few weeks it begins to dim, until it eventually ceases to exist; it's often replaced by a black hole. (Though remains that were shot out into space may survive; those of a great supernova seen in A.D. 1054 are now known as the Crab Nebula.) All this may serve as a warning to those human stars whose fame explodes too rapidly; supernovas of this kind have sometimes vanished by the following year.
Examples of supernova in a Sentence
Andy Behrens, New York Times, 17 Oct. 2025
Oh sure, there’s the occasional supernova and a bit of unrest as huge gas clouds collide and start to form stars.
—Phil Plait, Scientific American, 16 Oct. 2025
Betelgeuse, formally known as Alpha Orionis, will one day end its life in a spectacular supernova explosion upon exhausting the last of its fuel, which could be as bright as the full moon.
—Anthony Wood, Space.com, 14 Oct. 2025
Star, supernova, star, supernova, and so on.
—Big Think, 10 Oct. 2025
See All Example Sentences for supernova
Cite this Entry
“Supernova.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/supernova. Accessed 24 Oct. 2025.
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supernova
noun
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