China captures first photo of Earth's quasi-moon Kamo'oalewa — a house-sized rock

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China's first-ever asteroid sampling mission has sent home a picture of its first target, the "quasi-moon" Kamo'oalewa.

The Tianwen-2 probe launched in 2025 and traveled 620 million miles (1 billion kilometers) to reach a safe distance about 12 miles (20 km) away from Kamo'oalewa, more formally known as asteroid 2016HO3. The spacecraft will spend nearly a year studying the asteroid with a suite of 11 different scientific instruments before attempting to collect a sample from its surface, which will be sent back to Earth.

The new photo was taken on July 2, according to China's Xinhua news outlet , and reveals the asteroid to be a small, asymmetrical rock measuring around 50–65 feet (16–20 meters) in diameter. While its origin isn't known, some scientists believe this quasi-moon could have been created when a massive impact knocked a chunk of our own moon into space between 1 million and 10 million years ago.

So-called quasi-moons (or quasi-satellites) are small bodies like Kamo'oalewa that circle the sun on orbits that keep them close to our planet. Earth has at least seven known quasi-satellites , and our planet's gravity will occasionally capture others temporarily before they are flung back out into orbit around the sun. In general, the orbits of these quasi-moons are less stable than the orbits of true moons.

Unlike most near-Earth asteroids that are thought to originate from the main asteroid belt between Mars and Jupiter, Kamo'oalewa could have come from much closer to home. A 2024 study published in Nature Astronomy proposes Kamo'oalewa could be material ejected from the moon by the impact that formed Giordano Bruno crater .

Sample of the asteroid collected by Tianwen-2 could help prove that hypothesis, if the mission is successful.

An artist's impression of Kamo'oalewa near the Earth-moon system. (Image credit: Addy Graham/University of Arizona) Tianwen-2 launched on May 28, 2025 atop a Long March 3B rocket from Xichang spaceport in southwestern China. The appearance of the spacecraft wasn't revealed until China's space agency released an image beamed home by Tianwen-2 when it was 1.8 million miles (3 million km) away from Earth. This occurred just over a week past launch.

The first public image of China's Tianwen 2 spacecraft, released by China's space agency well after the spacecraft was on its way to its first asteroid target. (Image credit: CNSA) While Tianwen-2 marks China's first asteroid sample attempt, Japan and the United States have already performed successful space-rock-sample missions of their own. Japan's Hayabusa spacecraft executed the world's first asteroid sample return mission when it sent material from asteroid 25143 Itokawa back to Earth in 2010.

The United States accomplished the feat in 2023 with the OSIRIS-REx mission that snagged material from asteroid Bennu . Those samples have already produced surprising scientific data, including the fact they contain the amino acids we consider vital for life here on Earth.

Tianwen-2 is China's first-ever mission to an asteroid and its second planetary exploration mission overall. Its first interplanetary endeavor, Tianwen-1 , saw an orbiter and a rover reach Mars in 2020.

More Tianwen missions are in the works. China plans to launch the Tianwen-3 Mars sample-return mission in 2028 and Tianwen 4 two years later to study Jupiter and Uranus.