Astronomers have identified two giant exoplanets, each roughly the size of Jupiter, that possess densities lighter than cotton candy. These "super-puff" planets are the largest discovered to date with such low densities, orbiting a star located 1,110 light-years away in the constellation Volans.
Described by researchers as having densities comparable to "a nice blob of shaving foam, fresh from the can," the planets are thought to be primarily composed of hydrogen and helium. Their exact chemical makeup will be further investigated by NASA's Webb Space Telescope. These celestial bodies are significantly less dense than Jupiter, which is approximately 35 times denser than these newly found worlds.
Discovery and Characteristics
The planets were detected by NASA's Transiting Exoplanet Survey Satellite (TESS) over the past decade. Subsequent observations using Earth-based telescopes allowed astronomers to determine their orbits and calculate their densities. A light-year, the unit of distance used, is equivalent to nearly 6 trillion miles (9.7 trillion kilometers).
While the exact color of these planets is unknown, researchers speculate they might appear white or blue, depending on atmospheric conditions. The super-puff classification suggests these planets may have formed in environments rich in gas around a young star, later shedding much of their mass over time.
Super-Puffs in the Cosmos
Super-puff planets are considered rare in the known universe. According to astronomers, fewer than 40 such planets have been confirmed among NASA's tally of nearly 6,300 exoplanets discovered to date. Studying these unusual planetary types provides valuable insights into the processes of planet formation and humanity's place within the broader cosmos.
The findings were reported by a team led by George Dransfield of the University of Oxford in the journal Monthly Notices of the Royal Astronomical Society.