These seven alien worlds could help explain how planets form

The Earth-sized astronomical bounty circles a dim star that flew under the radar of exoplanet researchers.

Seven alien, Earth-sized worlds bask in the cool, red light of their parent star. The planetary menagerie exists around a star overlooked by other exoplanet hunters, although it is just 12 parsecs (39 light years) from Earth.

Astronomers have found other seven-planet systems before, but this is the first to have so many Earth-sized worlds. All of them orbit at the right distance to possibly have liquid water somewhere on their surfaces.

“To have this system of seven is really incredible,” says Elisa Quintana, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “You can imagine how many nearby stars might harbour lots and lots of planets.”

Some of the planets were announced last year, but the authors debuted five newfound ones in a paper published on 22 February in Nature1. Because the system is so close to Earth, astronomers can study the planets’ atmospheres relatively easily. That could reveal an astonishing diversity of worlds, ranging in composition from rocky to icy

Source: These seven alien worlds could help explain how planets form : Nature News & Comment