3 articles · Updated · The New York Times · Jul 17
Summary
A new study identified two giant planets about 1,100 light-years away that rank among the lightest known gas giants and are less dense than cotton candy.
The pair belongs to the rare “super-puff” class—planets whose tiny cores appear too small to pull in and hold such vast atmospheres under current formation models.
Typical gas giants need cores of at least 10 Earth masses, but many super-puffs have total masses below that threshold, deepening a puzzle first highlighted by three Kepler-51 planets found in 2014.
Researchers said the discovery could help map the outer limits of how planets form and evolve by testing explanations for these unusually bloated worlds.