NASA’s Transiting Exoplanet Survey Satellite (TESS) has identified two “super-puff” planets, TOI-791 b and TOI-791 c, which possess densities comparable to cotton candy. Located 1,113 light-years away, these Jupiter-sized worlds contain only 3.0% and 5.9% of Jupiter’s mass, respectively. Scientists confirm the planets are locked in a gravitational dance that allowed for the precise calculation of their extreme low-density attributes.
How do astronomers detect “super-puff” planets?
Detection relies on the transit method, where telescopes monitor a star for periodic dips in brightness caused by a planet crossing its path. According to NASA’s Ames Research Center, TESS observed the TOI-791 system for 1,122 days over seven years. This extended duration allowed researchers to confirm the orbits of TOI-791 b and TOI-791 c at 139 and 232 days. By analyzing the timing variations in these transits, scientists determined the planets gravitationally tug on each other, a process that provided the data necessary to calculate their remarkably low masses.
Most known exoplanets are either small and rocky like Earth or dense gas giants like Jupiter. “Super-puffs” are an outlier, representing a rare class of planets that challenge current models of how gas giants accumulate mass and atmosphere during formation.
Why are TOI-791 b and c significant for planetary science?
These planets provide a unique laboratory for studying planetary evolution because they exist in the same system. Lead author George Dansfield of Oxford University noted that finding two such low-density worlds in one system is rare. While a typical gas giant like Jupiter is dense and heavy, these super-puffs suggest that the process of large planet formation might be more diverse than previously theorized. Steve Howell, a NASA Ames research scientist, stated that further study of these planets is high-value because large planet formation is believed to drive the overall evolution of a planetary system.
What are the next steps in exoplanet research?
Future investigations will focus on the chemical composition of the atmospheres surrounding TOI-791 b and c. Researchers aim to determine how the planets’ spin rates influence their physical shape and how the tilt of the host star relates to the planetary orbits. According to the study published in the Monthly Notices of the Royal Astronomical Society, understanding these dynamics will help clarify whether the planets migrated through their system during their developmental phases or if their current orbits were shaped by long-term gravitational interactions.
Frequently Asked Questions
What is a “super-puff” planet?
A super-puff is an exoplanet with an extremely low density, often compared to cotton candy, meaning it has a large radius but very little mass.
How far away is the TOI-791 system?
The system is located approximately 1,113 light-years from Earth.
Why is it rare to find two super-puffs together?
According to Oxford University researchers, only a small number of these planets are known to exist, and the gravitational mechanics required to maintain two such light planets in one system are complex and uncommon.
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