Space mission shows Earth's water may be from asteroids: study

Graphic explaining how Japan's Hayabusa-2 space probe dropped off asteroid samples to Earth in December 2020 before starting a new mission.

Hayabusa-2 returned to Earth's orbit two years ago to drop off a capsule containing the sample

Water may have been brought to Earth by asteroids from the outer edges of the solar system, scientists said after analysing rare samples collected on a six-year Japanese space mission.

The scientists hypothesised that such material probably has an "outer Solar System origin", but said it was "unlikely to be the only source of volatiles delivered to the early Earth".