Earth has company on its journey around the Sun, and one small companion follows a particularly interesting route. The asteroid discovered as 2016 HO3 stays near our planet over long periods, appearing to loop around it when its motion is viewed relative to Earth.
That behaviour inspired headlines about a “second moon.” The more accurate term is quasi-satellite. It describes a relationship between orbits, not a second large natural satellite hanging beside the Moon in our sky.
Paul Chodas’s explanation in 2016
The 2016 article preserved Paul Chodas’s comparison with an earlier quasi-satellite:
“One other asteroid — 2003 YN107 — followed a similar orbital pattern for a while over 10 years ago, but it has since departed our vicinity. This new asteroid is much more locked onto us. Our calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth’s companion for centuries to come.”
He also described the slower change in the apparent loops:
“The asteroid’s loops around Earth drift a little ahead or behind from year to year, but when they drift too far forward or backward, Earth’s gravity is just strong enough to reverse the drift and hold onto the asteroid so that it never wanders farther away than about 100 times the distance of the moon.”
“In effect, this small asteroid is caught in a little dance with Earth.”
These were 2016 statements about a modelled orbital relationship. They do not make the asteroid a permanently bound second Moon. The original orbit video and its credit remain a useful companion to the explanation.
It goes around the Sun
NASA’s Jet Propulsion Laboratory explained the distinction in its June 2016 announcement. The asteroid is too distant to be considered a true satellite of Earth. Its primary orbit is around the Sun, while its orbital timing keeps it in a long-lasting relationship with our planet.
The object is now named Kamoʻoalewa, recorded under number 469219 in the JPL Small-Body Database. The original provisional designation, 2016 HO3, remains useful when following the discovery story.
How can it look as though it circles Earth?
Imagine watching two runners move around a track at slightly different speeds. From the stands, both are circling the track. From the viewpoint of one runner, the other seems to move ahead, fall behind and approach again.
The asteroid’s motion is three-dimensional and governed by gravity, so the running-track comparison is only a starting point. But it captures why the chosen viewpoint matters. A loop in an Earth-centred animation does not automatically mean the object is gravitationally bound to Earth in the same way as the Moon.
During part of its solar orbit, the asteroid moves ahead of Earth; during another part, it falls behind. Its tilted path also carries it above and below our planet’s orbital plane.
“Long-lasting” is different from “permanent”
JPL’s 2016 calculations described a stable quasi-satellite relationship extending across centuries. That is a substantial interval for a human observer, but it is not an assurance that the configuration lasts forever.
Small-body orbits evolve under gravitational influences. The useful question is which arrangement a calculation supports over a stated period, rather than whether a headline can promise a companion “here to stay.”
How to read an orbit illustration
First locate the Sun and check the viewpoint. Then find the paths labelled for Earth and the asteroid. Finally, read whether sizes and distances are to scale. Space illustrations often enlarge tiny objects so that they remain visible.
This habit is useful when exploring NASA’s DART asteroid-deflection experiment, too: a diagram can clarify motion without being a realistic photograph of the scene.
Kamoʻoalewa is interesting precisely because it is not an ordinary moon. Its orbit gives us a glimpse of the variety of relationships possible among small bodies in the solar system—and a satisfying reason to look twice at a familiar-looking animation.
A different orbital question asks whether a moon could have a smaller natural satellite of its own. Our guide to submoons explains why theoretical orbital stability and the discovery of an actual object are separate steps.
From discovery to a sample-return mission
The asteroid was found on 27 April 2016 by the Pan-STARRS 1 survey telescope on Haleakala, Hawaii, and was first estimated to be 40 to 100 metres (about 120 to 300 feet) across, small enough to explain why it had only just been spotted. JPL’s calculations kept it between about 38 and 100 times the Earth–Moon distance, so the “mini-moon” of 2016 headlines never comes close enough to pose a threat.
The object has since become far more interesting than the headline suggested. In 2021 astronomers reported that its spectrum resembles space-weathered lunar rock, raising the possibility that it is a fragment of the Moon, and in April 2024 a study in Nature Astronomy modelled an impact that could have thrown such a fragment off the far side, pointing to the Giordano Bruno crater as the likely source; that origin remains a hypothesis. China’s Tianwen-2 spacecraft was launched on 29 May 2025. On 6 July 2026 the China National Space Administration confirmed, through Xinhua, that the probe had entered orbit around Kamoʻoalewa on 7 June and released its first close-up photograph, taken from about 20 kilometres. Size estimates from that blurry image differ between reports: Astronomy put it at about 20 metres across, while Live Science reported about 40 metres, and noted that the asteroid looks like a loosely bound, fast-spinning rubble pile that CNSA says makes sampling more complex and risky. An independent estimate from James Webb Space Telescope observations, in a paper posted on July 1, 2026, put its diameter at about 18 metres. The rest is still a plan, not an achievement: the probe is to map the surface and choose a sampling site, try to collect a sample, and leave around April 2027, with any sample to be released in a capsule during an Earth flyby in November 2027 before the probe heads for the comet-like body 311P/PanSTARRS. If the sample confirms a lunar origin, Earth’s “second moon” will turn out to be a small piece of the first.
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Video and posts
Original references and creator profiles: Paul Chodas; movements are complicated; True Activist.
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Clearly they're trying to coverup the fact that earth is flat and many can simultaneously see the moon, which, depending upon where you are on a globe earth, would be impossible.
ReplyDeleteA little problem NASA is trying to resolve with another giant lie.
The bright red forked tongue strikes again
You need medication.
Delete