Posted on by Matt Williams

Instead of Losing its Atmosphere, an Exoplanet Puffed Up and Held Onto it

Artist's impression of the "hot Neptune" Phoenix orbiting its red giant star. Credit: Credit: Roberto Molar Candanosa/JHU

To date, astronomers have confirmed the existence of 5638 extrasolar planets in 4,199 star systems. In the process, scientists have found many worlds that have defied expectations. This is certainly the case regarding “hot Neptunes,” planets that are similar to the “ice giants” of the outer Solar System but orbit much closer to their stars. But when a Johns Hopkins University-led team of astronomers discovered TIC365102760 b (aka. Pheonix), they observed something entirely unexpected: a Neptune-sized planet that retained its atmosphere by puffing up.

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Posted on by Evan Gough

Are Low Density “Cotton Candy” Exoplanets Actually Just Regular Planets With Rings?

An artist’s conception of Piro and Vissapragada’s model of a ringed planet transiting in front of its host star. They used these models to constrain which of the known super-puffs could be explained by rings. Illustration is by Robin Dienel and courtesy of the Carnegie Institution for Science.

There’s a type of exoplanet that astronomers sometimes refer to as cotton candy planets, or super-puffs. They’re mysterious, because their masses don’t match up with their extremely large radii. The two characteristics imply a planet with an extremely low density.

In our Solar System, there’s nothing like them, and finding them in distant solar systems has been puzzling. Now a pair of astronomers might have figured it out.

Continue reading “Are Low Density “Cotton Candy” Exoplanets Actually Just Regular Planets With Rings?”