A Strange Quasi-Satellite Has Been Stalking Earth for Years, and China’s New Mission Just Reached It to Settle a Massive Cosmic Debate
Hello, neighbor.
China’s Tianwen-2 spacecraft just snapped the first-ever close-up image of Earth’s mysterious quasi-satellite, Kamoʻoalewa, or 2016 HO3, after a 13-month journey through space. According to NDTV, the image, taken from just 20 kilometres away, reveals the asteroid’s rugged, irregular shape, giving scientists their first detailed look at this rare cosmic neighbor.
Launched on May 29, 2025, Tianwen-2 is China’s first mission to collect asteroid samples and return them to Earth. Capturing the close-up of Kamoʻoalewa is a milestone that marks a major step forward in unraveling the secrets of one of the solar system’s most unusual objects. Kamo’oalewa isn’t Earth’s second moon, despite its nickname. Instead, it’s a quasi-satellite, a rare type of asteroid that orbits the sun while staying gravitationally tied to Earth.
From our perspective, it appears to loop around our planet, but it never actually gets close enough to be captured by Earth’s gravity. Measuring between 40 and 100 metres wide, it’s one of the smallest asteroids ever visited by a spacecraft. Scientists have only identified seven quasi-satellites of Earth.
This makes Kamo’oalewa a standout in our cosmic neighborhood
The Tianwen-2 mission spotted the asteroid on June 6 and gradually closed the distance over the following weeks. By July 2, the spacecraft was close enough to capture its first detailed images. The photos show a jagged, uneven surface, hinting at the asteroid’s turbulent history.
Researchers are particularly excited because previous telescope observations suggest Kamoʻoalewa might actually be a fragment of Earth’s Moon, blasted into space by an ancient impact. If the samples Tianwen-2 collects confirm this theory, it could rewrite our understanding of how these rare objects form and evolve.
The mission isn’t just about solving the mystery of Kamoʻoalewa’s origin. Scientists also hope to learn more about how quasi-satellites maintain their unusual orbits over millions of years.
Physicist Rongqiao Zhang, from the Lunar Exploration and Space Engineering Center, explained in a paper published in Space Science Reviews that Kamoʻoalewa’s orbit is uniquely stable. Its orbital period closely matches Earth’s, making it easier to track and study. The asteroid stays between 0.1 and 0.3 astronomical units (AU) from Earth, providing ideal conditions for communication and control during the mission.
Collecting samples from Kamoʻoalewa won’t be easy
According to the NY Post, the asteroid is tiny, spinning once every 28 minutes, and has an uneven gravitational field with few flat surfaces. Experts worry the spacecraft could bounce off during landing or lose samples during collection.
To tackle these challenges, Tianwen-2 is equipped with hovering and anchoring capabilities, allowing it to adapt to the asteroid’s tricky terrain. The mission team described the effort as far more complex than previous deep-space explorations, calling it a “completely new path for humanity’s exploration of the universe.”
If successful, the samples could answer fundamental questions about the origins of Earth’s quasi-satellites and how their orbits evolve over time. Researchers also hope to determine whether Kamoʻoalewa is a loose pile of rubble or a solid monolith, and whether it contains water or other volatile compounds. These insights could help scientists better understand the broader population of near-Earth asteroids and their potential threats to our planet.
The mission’s success so far is a testament to China’s growing capabilities in space exploration
Tianwen-2 launched from the Xichang Satellite Launch Center and traveled nearly one billion kilometres to reach Kamoʻoalewa. The spacecraft first detected the asteroid on June 6 and closed within 1,242 miles of it by June 19. The recent images, taken from just 20 kilometres away, mark the first time humanity has gotten a close look at this elusive object.
For now, the mission is focused on identifying a suitable landing site and collecting samples. If all goes according to plan, the samples will be returned to Earth later this year via a re-entry capsule. Until then, scientists will continue analyzing the data and images sent back by Tianwen-2, eager to uncover the secrets of this cosmic oddity.
Kamoʻoalewa’s discovery a decade ago by the Pan-STARRS 1 asteroid survey telescope in Hawaii sparked curiosity among astronomers. Its unusual orbit and proximity to Earth made it a prime target for study, but its small size and distance made it difficult to observe in detail. Now, thanks to Tianwen-2, researchers finally have the chance to study it up close.
The stakes are high, but the potential rewards are even higher. If Tianwen-2 succeeds, it will not only advance our understanding of quasi-satellites but also pave the way for future missions to explore other near-Earth objects. For now, all eyes are on Kamoʻoalewa as China’s spacecraft continues its historic mission, bringing us one step closer to unlocking the mysteries of our solar system.
(Featured image: NASA)
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