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
Jeanine Santucci, USA Today, 14 Aug. 2025
Since then, astronomers have observed a further 2,000 Type 1a supernovas with different telescopes.
—Robert Lea, Space.com, 24 July 2025
Astronomers have theorized that supernovas such as these are caused by two white dwarfs orbiting each other in a binary star system, when one of them consumes the other.
—Margherita Bassi, Smithsonian Magazine, 9 Apr. 2025
Thus, such a wealth of Type Ia supernovas should reveal hints at the secrets of dark energy.
—Robert Lea, Space.com, 20 July 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 22 Aug. 2025.
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supernova
noun
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