Tianwen-2 Enters Orbit Around Asteroid Kamooalewa on Sunday
China's Tianwen-2 probe enters orbit around asteroid Kamooalewa on Sunday, and amateur radio astronomers in Europe have already decoded its telemetry, independently confirming the spacecraft is healthy.
- China's Tianwen-2 probe performs its orbit-insertion manoeuvre around asteroid Kamooalewa on Sunday, June 7.
- Almost a year of study follows, with sample collection scheduled to begin on July 4.
- Amateur radio operators in the Netherlands and Germany have already recorded and decoded the probe's telemetry, independently confirming the craft is healthy.
- The return capsule lands in late 2027, after which the probe heads for comet 311P/PanSTARRS.
China’s Tianwen-2 probe reaches asteroid 469219 Kamooalewa on Sunday, June 7, and performs its orbit-insertion manoeuvre. The moment marks the shift from a cruise phase that has run since launch in May 2025 into the mission’s main science phase. Almost a year of study of the small body follows before the spacecraft attempts to collect a sample from its surface.
What makes this stage unusual is that the spacecraft is no longer tracked only by Chinese control centres. A group of amateur radio operators and astronomers in Europe has independently captured and decoded the probe’s telemetry, a rare case of independent confirmation that a craft this far out is sound and transmitting. The news arrives a few weeks after earlier reports about the orbit insertion itself, but it adds a fresh detail: a signal picked up from Earth outside official channels.
How did amateurs confirm the probe is healthy?
Radio astronomers gathered around the CAMRAS association, which operates a 25-metre dish at Dwingeloo in the Netherlands, recorded the probe’s X-band signal on May 25 and 26. Engineer Daniel Estevez then decoded the recordings and published the results on GitHub, and reception was confirmed on May 27 by the AMSAT-DL group in Bochum, Germany.
What they obtained was not merely proof that a signal exists, but readable telemetry, the data the spacecraft sends about its own status. That showed, from an independent source, that Tianwen-2 is operational. Observers plan to follow how the signal changes over the coming months as the probe closes in on the asteroid.
The work plan at Kamooalewa is detailed. The probe carries 11 scientific instruments and, during the mission, will descend from about 20 kilometres to as little as 600 metres above the surface, mapping the body before deciding where and how to take a sample.
What does the mission plan to bring back to Earth?
Sample collection is due to begin on July 4, 2026. The target mass is at least 100 grams, and according to another source between 200 and 1,000 grams of material. Two techniques are planned for collection:
- a touch-and-go method, in which the probe briefly descends and lifts off amid a cloud of gathered dust,
- anchoring, in which the craft attaches to the surface and stays fixed during sampling.
Under the plan, the probe leaves Kamooalewa on April 24, 2027, and the return capsule carrying the sample lands on Earth late that year. The mission does not end with delivery, because the probe then heads for comet 311P/PanSTARRS, a body with traits of both an asteroid and a comet, which it is expected to reach in 2035.
Engineers do not hide that the task is hard. On the mission’s challenges, Shen Cunliang of the China Aerospace Science and Technology Corporation said the following.
The hardest challenge we face lies in the large number of unknowns.
It is worth keeping in mind that entering orbit is not the same as taking a sample. Sunday’s manoeuvre is only the start of a long phase during which it will be decided whether the chosen techniques work on such a small body. What do you think: will the combination of two methods manage to bring back the required amount of material from an asteroid only a few dozen metres across?
