"Super puff" exoplanet is as big as Jupiter but 10 times lighter, confusing astronomers - CBS News

Jan 19, 2021

About 212 light years from Earth, a gas giant light enough to be nicknamed a "super-puff" or "cotton candy" planet is circling extremely close to its host star.

This super-puff exoplanet, known as WASP-107b, is about the same size as Jupiter, but only about one-tenth the mass — or about 30 times more massive than Earth.

According to a new study published Monday in The Astronomical Journal, its core mass is significantly smaller than astronomers thought necessary for the creation of a gas giant planet like Jupiter and Saturn. .

WASP-107b is one of the puffiest planets out there, and we need a creative solution to explain how these tiny cores can build such massive gas envelopes," coauthor Eve Lee said in a statement. .

The planet is very close to its star, over 16 times closer than Earth is to the sun, completing one orbit every 5.7 days. .

Scientists were shocked to conclude that the solid core of WASP-107b has a mass that is no more than four times that of the Earth, meaning more than 85% of its mass stems from the thick gaseous layer surrounding the core

Based on their knowledge of Jupiter and Saturn, scientists previously believed that a solid core at least 10 times the mass of Earth would be needed to acquire enough gas for a gas giant planet to form

"This work addresses the very foundations of how giant planets can form and grow," Benneke said