A Planet Bigger Than Jupiter, But Light as Cotton Candy

The further astronomers look into the Milky Way galaxy, the more strange and different planets they find. A newly-discovered exoplanet designated WASP-193b is one of those in the "puffy Jupiter" category. It is 50% larger than Jupiter, but has only about 14% of Jupiter's weight. What's it made of -Aerogel?

WASP-193b was discovered by the dip in light coming from the star WASP-193, which it revolves around every 6.25 days. The amount of light it blocked told us how large it is. Scientists tried defining its mass by measuring its gravitational pull on the star, but came up empty because it is so light that it exerts no detectable pull! Four years of data and calculations led them to the conclusion that this massive star is just that fluffy. Its density is estimated to be about 0.059 grams per cubic centimeter, close to that of cotton candy. Astronomers believe it is mostly made of hydrogen and helium.

Of 5,400 planets we know about, planet WASP-193b is the second lightest. Kepler 51d displays a lower density, but that planet is also much smaller. Read more about the cotton candy planet at MIT News. -via Real Clear Science​

(Unrelated image credit: ESO/M. Kornmesser)