Rosetta casts doubt on comets as Earth’s water providers
Comet 67P’s atmosphere contains a surprisingly high fraction of deuterium

GETTING FUZZY The basic chemistry of a comet’s thin, hazy atmosphere offers hints about how water got to Earth. It may not have been on the backs of comets like 67P/Churyumov–Gerasimenko.
NAVCAM/Rosetta/ESA (CC BY-SA IGO 3.0)
This article is only available to Science News subscribers.
Subscribers, enter your e-mail address to access our archives.
