New theory about the mysterious all-purpose Camo’Oleva: Is it the moon’s piece?

Updated on 11/11/2021, 5:06 PM

• The moon is not the only companion to the earth.
• Small boulders such as Kamo’oalewa orbit the sun near them.
• Researchers now have a theory about their origin.

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A celestial body just 45 to 60 meters high and continuing close to Earth may be a debris from the moon ejected into space during an asteroid impact. This is the conclusion reached by an American research team that has been observing the so-called semi-satellite for many years.

In particular, the color of the object showed no resemblance to asteroids, but with lunar rocks brought to Earth by Apollo astronauts, scientists explain in the journal “Communications Earth & Environment”.

Five small objects are constantly near the earth

Since 2004, astronomers have discovered a total of five small celestial bodies that are constantly close to Earth, but orbit the Sun freely. Astronomers refer to such celestial bodies as semi-satellites. When observed from Earth, their orbit seems to orbit our planet – as opposed to the direction of regular motion.

“Not much is known about these semi-satellites yet,” wrote scientists working with Benjamin Sharkey from the Lunar and Planetary Laboratory in Tucson, Arizona, “because they are so fragile and hard to notice.”

Over the years, the team has meticulously looked at the semi-satellite Kamo’oalewa, discovered in 2016 – the name derives from Hawaiian creative myth and means “descendant traveling alone” – the largest binocular telescope in Hawaii. The hard work is because the small celestial body can only be observed for a short time in April due to its orbit.

To their surprise, Sharky and his colleagues discovered that Kamo’oalewa’s spectrum was unlike any other known asteroid in near-Earth orbit. The researchers found a match compared to silicate rock from the moon. In addition, an accurate analysis of Kamo’oalewa’s orbit suggests that the smaller fragment originally came from the Earth-Moon system. Sharki’s colleague Renu Malhotra explains, “This orbit is different from near-Earth asteroids, and it is very unlikely that a normal asteroid near Earth would enter such an orbit.”

Kamo’oalewa may be rubbish thrown from the moon

Therefore, researchers believe that the explanation is that Camo’Oleva – and even other semi-satellites – are part of the debris emitted by asteroid impact on the moon. Another piece of evidence supports this hypothesis: Near Earth, Kamo’oalewa moves only at speeds of two to five kilometers per second – asteroids in near-Earth orbit typically move at 20 kilometers per hour.

However, researchers cannot say when the impact that Kamo’oalewa could have caused occurred – the object may have been stable near the Earth for millions of years, but not billions of years. (dpa / Rainer Kayser / mgb)