Kepler-51 is a
Sun-like star that is only about 500 million years old.
It is orbited by three
super-puff
A super-puff is a type of exoplanet with a mass only a few times larger than
Earth's but with a radius larger than that of Neptune, giving it a very low mean density. planets—Kepler-51b, c, and d—which have the lowest known densities of any exoplanet. The planets are all Jupiter-sized but with masses only a few times Earth's.
Planets
Kepler-51 has three planets, all super-puffs. Kepler-51b, c and d have some of the lowest known densities of any exoplanet.
References
Further reading
Kepler-51 is Home to Three Super-Puff Exoplanets Sci-News, Dec 20, 2019 by Natali Anderson
G-type main-sequence stars
Solar analogs
Planetary systems with three confirmed planets
Cygnus (constellation)
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