'Marshmallow' world defies expectations for planets orbiting red dwarf stars

https://phys.org/news/2022-03-jupiter-sized-exoplanet-tess.html, this report provided a mean density in grams.

"Using NASA's Transiting Exoplanet Survey Satellite (TESS), astronomers from the Pennsylvania State University (PSU) and elsewhere have detected a new Jupiter-sized extrasolar world. The newfound exoplanet, designated TOI-3757 b, is slightly larger than Jupiter but more than three times less massive than the solar system's biggest planet. The finding is reported in a paper published March 15 on arXiv.org…A group of astronomers led by PSU's Shubham Kanodia has recently confirmed another TOI monitored by TESS. They report that a transit signal has been identified in the light curve of an M dwarf star known as TOI-3757. The planetary nature of this signal was confirmed by follow-up observations...TOI-3757 b has a radius of about 1.09 Jupiter radii, while its mass is approximately 0.268 Jupiter masses. This yields a density of only 0.27 g/cm3, what makes it the lowest density planet orbiting an M dwarf known to date. The exoplanet orbits its host every 3.44 days, at a distance of some 0.038 AU from it..."

The Extrasolar Planet Encyclopaedia — TOI-3757 b (exoplanet.eu)

My observation. Using my astronomy spreadsheet and properties listed in the phys.org report, I calculate P = 4.4466E+00 day, a bit longer than shown. In 1 Gyr period this exoplanet could complete 8.2141E+10 or more than 82 billion revolutions around the parent star. The star is considered to be 7.1 Gyr old. Demonstrating that this exoplanet has been revolving for hundreds of millions of revolutions around the host star is another story :)
 
Okay, I plugged in the properties from the exoplanet.eu site and P = 3.4417E+00 or 3.44 days and mean density 0.27 g cm^-3. This looks better but in 1 Gyr, 1.0612E+11 or more than 106 billion revolutions completed. If the exoplanet has been moving around its host star like that for 7 Gyr, some 700 billion or more revolutions show up. TOI-3757 b at 0.268 Mjup is a bit more than 85 earth masses. Saturn a bit more than 95 earth masses.
 

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