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
Eric Berger, ArsTechnica, 8 Apr. 2025
Type 1a supernovas are very helpful for scientists, because supernovas tend to explode with roughly the same amount of energy.
—Julian Dossett, Space.com, 7 Apr. 2025
Identifying details in pre-explosion images can help inform the how, when and why supernovas occur.
—Robert Z. Pearlman, Space.com, 24 Mar. 2025
Over five years, their telescope in the Chilean Andes snapped high-resolution photographs of 12% of the sky, creating the most extensive catalog of supernovas to date and locating the same spherical shells traced out by many millions of galaxies (albeit with less precision than DESI).
—Charlie Wood, Quanta Magazine, 19 Mar. 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 23 Apr. 2025.
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supernova
noun
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