protostar
noun
pro·to·star
ˈprō-tō-ˌstär 
: a cloud of gas and dust in space believed to develop into a star
Examples of protostar in a Sentence
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The star, classified as IRAS 04302+2247, or IRAS 04302, is a protostar, with its disk measuring at around 40 billion miles (65 billion km) wide.
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Kenna Hughes-Castleberry, Space.com, 4 Sep. 2025
Instead, with this tweak to dark matter, the early protostar that forms will instead remain in a large, relatively cool state for a long time, which can grow the protostar up to 100,000 solar masses or even more.
—Ethan Siegel, Big Think, 2 Sep. 2025
These reflection nebulae shine because light from the protostar bounces off them, creating the butterfly-like shape.
—Rupendra Brahambhatt, Interesting Engineering, 30 Aug. 2025
Now, with the much bigger JWST, the full picture snaps into focus: the telescope captured this field of dust and debris just as a baby protostar (probably located somewhere on its lower right, outside the boundary of the image shown here) was blasting it into this very particular shape.
—Gayoung Lee, Scientific American, 12 Aug. 2025
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Kenna Hughes-Castleberry, Space.com, 4 Sep. 2025
Instead, with this tweak to dark matter, the early protostar that forms will instead remain in a large, relatively cool state for a long time, which can grow the protostar up to 100,000 solar masses or even more.
—Ethan Siegel, Big Think, 2 Sep. 2025
These reflection nebulae shine because light from the protostar bounces off them, creating the butterfly-like shape.
—Rupendra Brahambhatt, Interesting Engineering, 30 Aug. 2025
Now, with the much bigger JWST, the full picture snaps into focus: the telescope captured this field of dust and debris just as a baby protostar (probably located somewhere on its lower right, outside the boundary of the image shown here) was blasting it into this very particular shape.
—Gayoung Lee, Scientific American, 12 Aug. 2025
See All Example Sentences for protostar
Cite this Entry
“Protostar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protostar. Accessed 8 Sep. 2025.
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