A Chinese spacecraft that’s scheduled for launch as early as next month has a double destination: a “quasi-moon” of Earth and an asteroid that acts like a comet.
The first destination for Tianwen-2 is an asteroid, Kamo’oalewa. It’s a chunk of rock no more than the length of two or three football fields. What makes it intriguing is that it weaves around the Sun in a pattern that makes it look like a satellite of Earth.
The asteroid spends half of its time farther from the Sun than Earth is, the other half closer to the Sun. Seen from Earth, it appears to loop around our planet – like a moon. Some research suggests it was a chunk of the Moon that was blasted into space by a big impact.
Tianwen-2 is scheduled to arrive at Kamo’oalewa next year. It’ll spend a year traveling along with the asteroid. It’ll drop off a small lander and rover, and collect a few ounces of rocks and dirt.
The craft will swing by Earth to drop off the samples, then journey to 311P Panstarrs. The object is a third of a mile wide, and orbits the Sun at about twice Earth’s distance.
Observations reveal that Panstarrs is rocky, like an asteroid. But soon after it was discovered it sprouted several long tails, so it was classified as a comet. It may be a loosely bound pile of rocks and dust. If so, it may sometimes lose some of the dust, and sunlight then pushes it away – giving this asteroid the tails of a comet.
Script by Damond Benningfield