Image Courtesy: NASA
Astronomers have identified two giant exoplanets larger than Jupiter but with densities so low that they are comparable to cotton candy or shaving foam, making them the lightest planets ever discovered for their size.
The newly discovered worlds orbit a star about 1,110 light-years from Earth in the southern constellation Volans. Despite their enormous size, the planets are composed primarily of hydrogen and helium and have densities far lower than any gas giant of similar dimensions. The discovery was made using data from NASA’s Transiting Exoplanet Survey Satellite (TESS).
The research was led by George Dransfield of the University of Oxford and published in the Monthly Notices of the Royal Astronomical Society. Dransfield described the planets as having densities comparable to “a nice blob of shaving foam, fresh from the can,” highlighting just how unusually light they are.
Known as “super-puffs,” these rare planets are significantly less dense than typical gas giants. Jupiter, for example, is up to 35 times denser than the newly discovered pair. Although they are roughly Jupiter-sized, their extremely low density suggests they contain vast, extended atmospheres dominated by hydrogen and helium.
Super-puff planets are among the rarest types of exoplanets. NASA has confirmed nearly 6,300 exoplanets to date, yet fewer than 40 fall into this unusual category. Scientists believe these planets form within gas-rich disks surrounding young stars before gradually losing much of their atmospheric material over billions of years.
Researchers hope the discovery will provide new insights into how planetary systems evolve and why some worlds retain such unusually inflated atmospheres. Studying these extreme planets could also help astronomers refine existing models of planet formation and better understand the diversity of worlds beyond our solar system.
