Our Hawaiian moon, Kamoʻoalewa.

[AaronM]

A mysterious object near the Earth is the first known space rock made of what looks like a piece of the moon, a new study reveals. It may, in fact, have split off the moon in an ancient collision with an asteroid.

The space rock, called Kamo'oalewa, was discovered in 2016. It has been the target of study by Vishnu Reddy, an associate professor in cosmochemistry and planetary astronomy at the University of Arizona, and his PhD student Benjamin Sharkey. 

Reddy regularly studies space rocks discovered in the vicinity of Earth for NASA's Planetary Defence Coordination Office, which keeps track of space-based dangers. Kamo'oalewa, however, had resisted his attempts to analyze its composition for several years.

When Sharkey showed Reddy his latest observations of the elusive space rock, the two couldn't believe their eyes. 

"We couldn't believe the way it was looking because it was unlike anything we've seen before," Reddy told Space.com.

The results, Reddy said, didn't match any of the known more than 2,000 near-Earth asteroids analyzed before.

https://www.space.com/near-earth-space-r...n-material

https://www.livescience.com/amp/kamooale...n-fragment

[TomK]

"Our Hawaiian moon"? Seriously? I won't even comment on the plagiarism.

[AaronM]

Blah, blah, blah. I don't know what you said but I'm sure it was the definition of pompous.

Moving right along,

The asteroid Kamo`oalewa passes within 9 million miles of Earth every April. It may have once been part of our moon.

A small asteroid orbiting close to Earth could be a fragment of the moon that snapped off during an ancient impact, according to new research published Nov. 11 in the journal Communications Earth & Environment.

If confirmed, that would make the asteroid the first near-Earth object with a known lunar origin — and could help shed light on the chaotic history of our planet and its pockmarked companion, the researchers said.

The asteroid in question is called Kamo`oalewa — a Hawaiian word that roughly means "the oscillating celestial fragment" — and was discovered in 2016 by astronomers using the PanSTARRS telescope in Hawaii.

Though the object is about 4 million times fainter than what humans can see with the naked eye, every April the rock's orbit brings it close enough to Earth that it becomes briefly visible to our most powerful telescopes. (In this case, "close enough" means about 9 million miles, or 14.4 million kilometers, from Earth — or nearly 40 times the distance between Earth and the moon).

Observations showed that the asteroid measures about the size of a ferris wheel, with a diameter of no more than 190 feet (58 meters).

Because of its near-Earth orbit, Kamo`oalewa fits into a category of celestial objects called quasi-satellites — essentially, objects that orbit the sun, but stay pretty close to Earth. Astronomers have detected plenty of quasi-satellites before, but they have a hard time studying them in detail, given the objects' typically small size and incredible dimness.

The origins of such tiny travelers are hard to pin down — but the authors of the new paper made an attempt to uncover Kamo`oalewa's secrets by studying the faint patterns of reflected light on its surface. Using the Large Binocular Telescope on a mountaintop in southern Arizona, the researchers watched Kamo`oalewa closely during its regular April visits for several years.

They found that the asteroid's light spectrum matched that of lunar samples from NASA's Apollo missions almost perfectly, suggesting the ferris-wheel-size boulder may be a loose piece of lunar debris. Furthermore, the asteroid's orbit — which is incredibly similar to Earth's — is atypical of the rocks that make their way toward our planet from the outer solar system, the researchers added. It seems more likely that the rock has been near us for a long time.

"It is very unlikely that a garden-variety near-Earth asteroid would spontaneously move into a quasi-satellite orbit like Kamo`oalewa's," study co-author Renu Malhotra, a planetary sciences professor at the University of Arizona, said in a statement.

If Kamo`oalewa is a piece of the smashed-up lunar surface, it's unclear what exactly kicked it loose, or how it ended up in its current orbit; no near-Earth object with a lunar origin has ever been detected before, the researchers wrote. However, after analyzing the rock's orbit, the team found three other near-Earth asteroids with similar enough orbital patterns that they could be considered "companions" to Kamo`oalewa; all of the rocks may have been ejected into space during the same ancient lunar impact.

More research on these quasi-satellites is required to pin down their origins. Luckily, researchers have a few hundred more Aprils to check in with Kamo`oalewa. According to the study authors, the asteroid will remain in its current orbit for another 300 years or so before finally escaping into space.

https://www.livescience.com/amp/kamooale...n-fragment

[TomK]

The only pompous bit is claiming the object is ours. Several hundred lunar meteorites have been discovered over the years, we know that impacts on the moon create chunks of rock that will invariably end up in a moon/earth orbit. This means it is not "the first known space rock made of what looks like a piece of the moon". The reason it was given a Hawaiian name is due to the involvement of Pan-STARRS. Many astronomical objects have been given Hawaiian names, but it doesn't mean they are ours, and Kamo`oalewa is not a moon, it's an asteroid or, as the researchers suggest, a quasi-satellite. Moons have stable orbits around their planet, Kamo`oalewa doesn't, it actually orbits the sun, not the earth.

I don't know what it is with some people. They say they don't read your posts and then respond to them anyway.

[eightfingers2.0]

“The only pompous bit is claiming the object is ours.”

Kind of like Mauna Kea, huh?


No one actually “owns” anything. They just “borrow” it for a while.

[AaronM]

"Ours" as in the collective of humanity. Our sky, our sea, our mountain, our moon.

[TomK]

"Ours" as in the collective of humanity.  Our sky, our sea, our mountain, our moon.

No, that's not how you phrased the title of this thread. "Our Hawaiian" does not equal "Our" and it isn't even a moon. You can take this to a logical conclusion given your response. It seems that someone can say "our Hawaiian sky, our Hawaiian sea, our Hawaiian mountain" but in your words, means it belongs to everyone else on the planet. So why even say "Hawaiian"? The argument falls apart even before the factoring in that the object isn't a moon and clearly isn't ours to start with; it orbits the sun.

[malahini]

At this point TomK is just harassing AaronM.

[TomK]

At this point TomK is just harassing AaronM.

How is it harassment?  Someone posts something that is clearly wrong and it gets pointed out. Is it a moon? No. Is it Hawaiian? No. Is it harassment? You be the judge. I think it's only fair that if someone posts something online then someone else can point out that it's wrong. If you have a problem with that then as far as I'm concerned you're a cry-baby and can't handle criticism.

Now, if you want to defend Aaron's comments in this post, please go ahead, post them rather than trying to deflect.

[malahini]

Well, I guess you got me there. What can I say?