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im·pac·tor | \ im-ˈpak-tər 
\
\variants:
or impacter
Definition of impactor
1 : a machine (such as a steam or air hammer or a pile driver) or part that operates by striking blows
2 : meteorite
Examples of impactor in a Sentence
Recent Examples on the Web After smashing into Pallus some 1.7 billion years ago, the impactor might have shattered into fragments, which then drifted out into space and began to trail their leader.
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Katherine J. Wu, Smithsonian Magazine, "The Most Cratered Object in the Asteroid Belt Looks Like a Golf Ball," 13 Feb. 2020 Scientists have suggested that the impactor was about 10 percent of the mass of Earth — just larger than Mars.
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Fox News, "5 interesting facts about the moon," 16 Mar. 2020 Further Reading End-Cretaceous asteroid impact seems to have juiced seafloor volcanoes
After the skies cleared, potent global warming set in for the long haul due to the CO2 produced when the impactor evaporated bedrock to make the impact crater.
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Scott K. Johnson, Ars Technica, "End-Cretaceous mass extinction saw big swings in ocean pH," 24 Oct. 2019 After the large impactor smashed into the planet, some of the debris formed a disk that flew up to circle the Martian equator.
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Nola Taylor Redd, Space.com, "Giant Impact May Have Created Mars' Moons," 18 Apr. 2018 This consisted of a lunar orbiter and an impactor that helped confirm the existence of water ice on the Moon.
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Eric Berger, Ars Technica, "India has launched an ambitious mission to the Moon," 22 July 2019 Computer simulations also revealed that the impactors responsible for Pallus’ craters were traveling at speeds over 25,000 miles per hour—nearly twice as fast as is typical for asteroid belt collisions, reports Charles Q. Choi for Space.com.
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Katherine J. Wu, Smithsonian Magazine, "The Most Cratered Object in the Asteroid Belt Looks Like a Golf Ball," 13 Feb. 2020 To figure out how the asteroid family could have formed, the researchers built a model that allowed them to try out different collisions, testing different impactor sizes and angles of impact.
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John Timmer, Ars Technica, "Collision liquified the 4th-largest asteroid, turning it into a dwarf planet," 29 Oct. 2019 This mission will use a kinetic impactor to try and deflect the smaller component of the binary asteroid, Didymos, which has a diameter of 160 meters.
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Eric Berger, Ars Technica, "It looks like NASA is getting serious about finding hazardous asteroids," 23 Sep. 2019
See MoreThese example sentences are selected automatically from various online news sources to reflect current usage of the word 'impactor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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Time Traveler for impactor
The first known use of impactor was in 1872
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