Scientists fetch best images to of 'dog bone' asteroid and 2 tiny moons

The space.com report states, "Rubble pile asteroids likely form from debris coalescing after a giant impact, but the new analysis also suggests that AlexHelios and CleoSelene came from Kleopatra itself. That theory is based on the determination that Kleopatra is spinning so quickly that if it sped up much it would simply fling itself to pieces. According to the researchers, that means that even collisions with small rubble might pull pebbles off the main asteroid's surface that could then coalesce into the moons."

Indeed, (216) Kleopatra is an interesting, triple asteroid system. Here are some other reports out on the asteroid. https://phys.org/news/2021-09-eso-captures-images-peculiar-dog-bone.html

Reference paper, An advanced multipole model for (216) Kleopatra triple system, https://arxiv.org/abs/2105.09134v1, 19-May-2021.
Reference paper, (216) Kleopatra, a low density critically rotating M-type asteroid, https://arxiv.org/abs/2108.07207, 16-August-2021.

My observation. The 10 page arXiv paper, https://arxiv.org/pdf/2105.09134v1.pdf My note. This triple asteroid system is not long lived it appears. Statements like this suggest a young, triple asteroid system under observation. "For SPHERE2017 and SPHERE2018, the χ2 for the nominal P’s was excessively large. It is an indication that the true periods might be either shorter or longer. Consequently, we computed periodograms (as χ(P)) for a wide range of periods (see Figs. 2, 3). It was quite important to start with P2, because the true period is longer, and this allowed us to realize that P1 is also longer. Otherwise, P1, P2 were so close to each other that the moon system became totally unstable."

Reference paper, An advanced multipole model for (216) Kleopatra triple system, https://arxiv.org/abs/2105.09134v1, 19-May-2021. "To interpret adaptive-optics observations of (216) Kleopatra, we need to describe an evolution of multiple moons, orbiting an extremely irregular body and including their mutual interactions. Such orbits are generally non-Keplerian and orbital elements are not constants."

Given the reference papers cited in the phys.org report and space.com, I did not see explained how these multiple asteroid systems can remain stable for 4.5 billion years or billions of years. Main belt asteroids could complete more than 227 million revolutions around the Sun in a period of one billion years. There are reports on binary asteroids in the main belt, including near earth objects too as well as triple systems like (216) Kleopatra. Are these binary and triple asteroid systems stable over billions of years or evidence for a recent origin and catastrophism in the solar system? The September issue of Sky & Telescope has a report on Saturn, rings, and moons. It turns out that young rings are not ruled out, Mimas may not orbit stable at Saturn for more than 1.5 billion years, and Titan is moving away much faster than previously thought, at least 11/cm yr^-1. There are many reports out now showing young surface features on different bodies too.
 

This report and discussion indicates various NEO/NEAs are not long lived in the solar system, commonly <=10 million years if that long.
 

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