Shrinking Exoplanets: Worlds Like Cotton
A distant star is orbited by four unusually low-density planets that are still very young and are expected to lose their fluffiness as they age.
The mystery of 'shrinking planets' solved: this is how the most common worlds in the Universe are formed
The observation of four 'baby' planets with unusually low densities demonstrates how planetary systems evolve and why our Solar System is a rarity.