China's Tianwen-2 spacecraft has closed in on asteroid 2016 HO3 after a 400-day journey and begun scientific exploration.
The Tianwen-2 spacecraft has reached a distance close enough to begin scientific exploration of the asteroid, the China National Space Administration said on its website.
Formally designated 2016 HO3, or asteroid 469219 Kamo‘oalewa, the target is an Apollo-type near-Earth asteroid. Earlier estimates placed its diameter at 40 to 100 metres, but images captured by Tianwen-2 suggest it is likely less than 40 metres across.
“Based on the image released so far, this asteroid appears to be somewhat smaller than previously predicted – it seems to be only about 20 to 30 metres across, whereas the earlier estimate from our paper was around 57 metres,” said Zhang Pengfei, a researcher from the Institute of Geochemistry at the Chinese Academy of Sciences.