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This week, astronomers are seeing double. Just a day after Japan\u2019s spacecraft flew by a strange, two-lobed asteroid named Torifune, China\u2019s space agency announced that its own robotic envoy had arrived at another space rock \u2014 an angular, compact object named 469219 Kamo\u02bboalewa.<\/p>\n
China\u2019s spacecraft, Tianwen-2, has been hunting down its target \u2014 a so-called quasi-moon \u2014 ever since it launched from Earth in May 2025. Finally, after a 400-day voyage around the solar system, it got within 12 and a half miles of the asteroid\u2019s surface, allowing the spacecraft to take its first detailed photograph.<\/p>\n
Pointy, asymmetric and just 60 feet in length, Kamo\u02bboalewa looks very different from the far more rubbly and rotund asteroids that various uncrewed spacecraft have visited in recent years.<\/p>\n
\u201cKamo\u2018oalewa looks amazing, like nothing we\u2019ve seen floating in space before,\u201d said Sabina Raducan, a researcher at the International Space Science Institute in Bern, Switzerland.<\/p>\n<\/div>\n<\/div>\n
Its craggy, diminutive nature suggests a dramatic origin story \u2014 perhaps a high-speed collision between two large asteroids. \u201cIt could be a remnant of a catastrophic event,\u201d said Cristina Thomas, a planetary scientist and planetary defense researcher at Northern Arizona University.<\/p>\n
As a quasi-moon, Kamo\u2018oalewa loops around and keeps in lock-step with Earth, but it\u2019s not a genuine moon because it\u2019s gravitationally tied to the sun. It poses no danger to us, but quasi-moons like Kamo\u2018oalewa offer clues as to how asteroids that started life between Mars and Jupiter ended up at Earth\u2019s doorstep \u2014 something that scientists concerned about potentially killer asteroids are keen to learn more about.<\/p>\n
Tianwen-2 won\u2019t just admire this asteroid from afar. After conducting science observations from above, it will swoop down and collect some pristine asteroid matter from Kamo\u02bboalewa before returning it to Earth in late 2027.<\/p>\n
\u201cThe sampling is definitely going to be challenging,\u201d Dr. Raducan said. But if China pulls it off, it will become the third nation to lift material directly from an asteroid, after Japan and the United States.<\/p>\n<\/div>\n<\/div>\n
Tianwen-2, whose name is often translated to \u201cQuestions to Heaven,\u201d traveled 620 million miles through space to rendezvous with the asteroid, which is \u201cabout the length of a bowling lane,\u201d Dr. Thomas said. \u201cKamo\u2018oalewa is the smallest object that humans have visited with a spacecraft.\u201d<\/p>\n<\/div>\n<\/div>\n
Based on Tianwen-2\u2019s first photo, the asteroid resembles a rocky splinter. \u201cIt looks exactly like an intact shard that we get from impact experiments in laboratory,\u201d Dr. Raducan said.<\/p>\n
Scientists briefly wondered if Kamo\u2018oalewa might be a chunk of our own moon, created by an asteroid impact millions of years ago.<\/p>\n
That theory has fallen out of favor. Scientists found that it\u2019s much more likely that Kamo\u2018oalewa started out as an object in the main belt of asteroids just beyond Mars.<\/p>\n
A recent, preliminary examination of Kamo\u2018oalewa using the remarkably perceptive James Webb Space Telescope also revealed it to be a very reflective object, and not something darker and moon-like. This survey also uncovered hints that its surface composition is akin to a rare type of meteorite known as an aubrite.<\/p>\n<\/div>\n<\/div>\n
Aubrites are particularly exciting because they might come from a massive, smashed-up asteroid-like object that had its own active geologic processes, including those that made magma, rocky layers and perhaps even a metal core \u2014 almost like a miniature planet. It\u2019s possible that Kamo\u2018oalewa may be the remains of something similar.<\/p>\n
For now, nobody can be certain as to what exactly Kamo\u2018oalewa may be. \u201cIt takes coordinated efforts across several disciplines to find the story that can explain everything best,\u201d said Benjamin Sharkey, a planetary scientist at the University of Maryland.<\/p>\n
But, if all goes according to plan, we\u2019re about to find out the truth. Sometime in the next few months, Tianwen-2 will plunge toward Kamo\u2018oalewa and attempt to extract some of its rocky debris in one of several ways, including using jets of gas to agitate the surface grains into a container, and anchoring itself to the asteroid before drilling into it. Should it succeed, the spacecraft will depart Kamo\u02bboalewa with the goods in April 2027.<\/p>\n
But the asteroid won\u2019t make it easy for China.<\/p>\n
When the United States and Japan brought asteroid samples to Earth, the samples were pebbly objects barely held together by their own gravity. While interacting with them had their own spaceflight challenges, scooping them up into a storage capsule wasn\u2019t too difficult.<\/p>\n
Kamo\u2018oalewa, however, may be a solid, rigid rock. \u201cIt\u2019ll be the first time we visited something like that,\u201d said Andy Rivkin, a planetary scientist and planetary defense researcher at Johns Hopkins Applied Physics Laboratory in Laurel, Md.<\/p>\n<\/div>\n<\/div>\n
The quasi-moon\u2019s Hawaiian name means \u201cwobbling celestial object.\u201d As it swivels around once every 28 minutes, it\u2019s more like a rapidly moving spinning top \u2014 something that could imperil Tianwen-2\u2019s touchdown.<\/p>\n
And the fact that Kamo\u2018oalewa is so tiny means that Tianwen-2 \u2014 which, weighing around two tons, is no pipsqueak \u2014 could have an outsize effect on the asteroid itself. \u201cThe hope is that while drilling, the spacecraft doesn\u2019t push the asteroid on a different orbit,\u201d Dr. Raducan said, \u201cgiven that their relative sizes are so similar.\u201d<\/p>\n<\/div>\n<\/div>\n