Seven Earth-Sized Planets in the Spotlight

Science News top 10 stories of 2017: Possibly life-friendly worlds orbiting TRAPPIST-1 fuel debate about what makes a habitable planet.

Remember that flurry of exoplanet stories back in spring 2017? Perhaps, it will come as little surprise that as popular science publications and websites begin publishing their "best-of-2017" lists, the discovery of seven earth-sized planets orbiting TRAPPIST-1 announced in February, has made Science News' list of top 10 science stories for 2017. Coming in at number five, behind LIDO and CRISPR, the Larsen C ice shelf break and new work pushing Homo sapiens’ emergence back to around 300,000 years ago.

Kudos to Julien de Wit and his collaborators for their discovery of TRAPPIST-1a through h, and fueling debate about what makes a habitable planet.

Read this story at Science News | Magazine issue: Vol. 192, No. 11, December 23, 2017, p. 25

Planets orbiting the star TRAPPIST-1 are a lot alike in some ways and distinct in others. Below shows each planet’s specs, including how long it takes to orbit the dwarf star, distance from the star (in astronomical units), and radius and mass relative to Earth. Slides: JPL-CALTECH/NASA