NASA’s Transiting Exoplanet Survey Satellite (TESS) has identified two of the least dense planets ever discovered, described by the agency as “cotton candy” worlds. These planets, located in the same star system, are comparable in size to Jupiter but possess only a fraction of its mass, making them exceptionally light and airy.
Rare ‘Super Puffy’ Worlds Found Together
One of the newly identified planets, TOI-791 b, is roughly the same size as Jupiter but has just three percent of its mass. The second planet, TOI-791 c, is even larger than Jupiter, yet its mass is only 5.9 percent of Jupiter’s. This extreme difference between size and mass results in a density comparable to cotton candy.
The discovery was made by a research team led by George Dansfield of Oxford University’s Department of Physics, utilizing data from TESS. Dansfield noted that “super puffy” planets are rare, and finding two such worlds within the same star system makes this discovery even more significant.
Steve Howell, a NASA Ames research scientist, highlighted the importance of studying these planets. He stated that understanding large planet formation is believed to be a key driver in the evolution of planetary systems. Therefore, “further study of these Jupiter-size, but far less than Jupiter-mass, planets is of high value.”
TESS Mission and Planetary System Insights
Launched in 2018, TESS was designed to detect exoplanets relatively close to Earth. The spacecraft surveys a much larger area than previous missions like Kepler, having identified 7,931 exoplanet candidates to date, with 897 already confirmed. For this specific planetary system, TESS collected 1,122 days of data over seven years.
Analysis of this data revealed that the two puffy planets have unusually long orbits, adding to their rarity. They are also gravitationally interacting, causing them to tug on each other. This interaction influences the timing of their transits across their host star, a variation that scientists used to calculate their masses.
Researchers are still seeking to understand many aspects of these celestial bodies, including the chemical composition of their atmospheres, the effect of their rotation on their shape, and the formation processes of such “cotton candy” planets.
Norman Pearlstine is the Chief Editor of News Raise and focuses on Business news. His responsibility is to oversee the editorial content including business, commodities, personal investments and the stock market.
