The asteroid Kamo’oalewa is considered a quasi-satellite of the earth. Now researchers are publishing new data and a theory: is the tiny asteroid a fragment from the moon?
Tucson – The earth is orbited not only by a moon, but also by five so-called quasi-satellites, small asteroids that orbit the sun in an orbit similar to the earth and therefore do not move from its side. Little is known about these quasi-satellites because they are small and difficult to observe. Only once a year – in April – large telescopes on earth have the opportunity to observe the most stable quasi-satellite on earth, the asteroid (469219) Kamo’oalewa. Researchers working with astrophysicist Benjamin Sharkey (University of Arizona) have seized this opportunity and now in the journal Communications Earth & Environment published a study on the little known little earth companion.
In their study, Sharkey’s researchers suggest that (469219) Kamo’oalewa must be related to the moon. To come to this conclusion, Sharkey’s research team examined, among other things, the reflection spectrum of the small asteroid – i.e. the light it reflects. It turned out that Kamo’oalewa has a reddish surface. This indicates a silicate-based composition, write the authors of the study. However, the material is more reddish than what you normally see in asteroids in the inner solar system. The material most closely resembles lunar rock, the NASA-Astronauts * of the mission “Apollo 14” brought from the moon to earth.
Asteroid (469219) Kamo’oalewa is a quasi-satellite of the earth – does it come from the moon?
But where does the asteroid Kamo’oalewa come from? The researchers also deal with this question in their study and develop several theories at the same time. One possibility is that the small celestial body, whose diameter is estimated to be less than 100 meters, is a simple near-earth object (NEO). Stable Trojan asteroids that have not yet been discovered could also be a possible origin for Kamo’oalewa, the researchers write. The theory, to which the researchers devote the most space in their study, has to do with the moon – understandable, given the nature of the small asteroid.
The researchers describe that Kamo’oalewa could be a fragment of the moon that was detached when it hit the surface of the moon. “The reflection spectrum of Kamo’oalewa supports the hypothesis of lunar sputum,” the study continues. And the low speed of the small asteroid as it approaches the earth and moon is an indication that the celestial body probably originates from the earth-moon system or from its vicinity, the authors continued. After all, objects close to the earth would have higher speeds when approaching the earth.
Quasi-satellite Kamo’oalewa “caught in the dance with the earth”, says a NASA expert
The asteroid Kamo’oalewa, also called 2016 HO3, was discovered in April 2016. * “The asteroid is caught in a little dance with the earth,” said Paul Chodas from NASA’s program for near-earth objects (NEO) at the time. The Hawaiian name Kamo’oalewa refers to an oscillating celestial object. The quasi-satellite of the earth needs 366 days to orbit the sun, its distance to the central star is almost exactly the same as the distance that the earth has to the sun.
The orbit of Kamo’oalewa brings the quasi-satellite up to about 16 million kilometers from the earth (perigee), its maximum distance from the earth (apogee) is as great as 100 times the distance between earth and moon. Calculations show that Kamo’oalewa has been a stable quasi-satellite on Earth for almost a hundred years. However, around 2341, it will change its orbit to assume a horseshoe orbit. (tab) * fr.de is an offer from IPPEN.MEDIA.
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