Mystery deepens: First ‘Candy Floss’ planet discovered near a red dwarf star

For the first time, astronomers have discovered an unusually light exoplanet orbiting a red dwarf star. This gives the so-called “cotton candy planets” mystery another twist. Red dwarfs are especially small and faint, but at the same time they are particularly active, and therefore they are not an environment in which unusual exoplanets are expected. However, the research team that has now discovered TOI-3757 b already has two possible explanations for this extraordinary discovery.

Lots of questions, possible answers

“Cotton candy planets” or “puffy planets” have been found for years. This is the so-called very low density exoplanets. Meanwhile, many are known to only reach values ​​between 0.06 and 0.31 g/cm³ Come on if you divide the measured mass by the given radius. Soil up to 5.5 g/cm³Saturn is the planet in the Solar System with the lowest density at 0.69 g/cm³. For TOI-3757 b, the research team Based on previous observation data, only 0.27 g/cm³ Identifies. That would leave the exoplanet comfortably floating on a large ocean of water, according to a popular analogy. The exoplanet is about the size of Jupiter and orbits its star once every three and a half days on Earth.

TOI-3757 b has now been detected in data from the TESS space telescope. As the researchers responsible explained, it was previously believed that a red dwarf star would quickly rob such a light exoplanet from its atmosphere with powerful eruptions. How such an exoplanet could ever form there under these conditions is a mystery.

Astronomers explain that TOI-3757 is made up of relatively few heavy elements, which is why exoplanets can form more slowly than the matter there, which can affect the overall density. In addition, the celestial body regularly approaches the star in its orbit, which is why it can swell again and again due to heat. Future observations using the James Webb Space Telescope may provide answers. research work Now appeared in The Astronomical Journal.

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