Seven Earth-sized planets entered the spotlight this year | Science News

SUPPORT SCIENCE NEWS

Help us keep you informed.

Real Science. Real News.


Year in Review

Seven Earth-sized planets entered the spotlight this year

Possibly life-friendly worlds orbiting TRAPPIST-1 fuel debate about what makes a habitable planet

By
8:29am, December 13, 2017
illustration of TRAPPIST-1

SEVEN IN ONE GO  The small, cool star TRAPPIST-1, illustrated here, hosts a bevy of Earth-sized planets. There could be many more stars like it worth studying.

Discoveries of planets around distant stars have become almost routine. But finding seven exoplanets in one go is something special. In February, a team of planet seekers announced that a small, cool star some 39 light-years away, TRAPPIST-1, hosts the most Earth-sized exoplanets yet found in one place: seven roughly Earth-sized worlds, at least three of which might host liquid water (SN: 3/18/17, p. 6).

These worlds instantly became top priorities in the search for life outside the solar system. “TRAPPIST-1 is on everybody’s wish list,” says exoplanet astronomer Lisa Kaltenegger of Cornell University. But the planets and their dim star have also stoked a

This article is only available to Science News subscribers. Already a subscriber? Log in now. Or subscribe today for full access.

Get Science News headlines by e-mail.

More from this issue of Science News

From the Nature Index Paid Content