NASA’s TESS (Transiting Exoplanet Survey Satellite), has found a 3rd small planet outdoors our solar system, scientists introduced this week on the annual American Astronomical Society assembly in Seattle. The brand new planet, named HD 21749b, orbits a vibrant, close by dwarf star about 53 mild years away, within the constellation Reticulum, and seems to have the most extended orbital interval of the three planets to date recognized by TESS. HD 21749b journeys round its star in a comparatively leisurely 36 days, in comparison with the two different planets — Pi Mensae b, a “super-Earth” with a 6.3-day orbit, and LHS 3844b, a rocky world that speeds around its star in merely 11 hours. All three planets have been found within the first three months of TESS observations.
The floor of the brand new planet is probably going around 300 levels Fahrenheit — comparatively cool, given its proximity to its star, which is as vivid because the solar. “It’s the best small planet that we all know of round a star this brilliant,” says Diana Dragomir, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research, who led the brand discovery. “We all know so much about atmospheres of scorching planets. However, as a result of it’s very exhausting to search out small planets that orbit farther from their stars, and are subsequently cooler, we haven’t been capable of study a lot about these smaller, cooler planets. However, right here we had been fortunate, and caught this one, and might now examine it in the additional element.”
The planet is about three times the scale of Earth, which places it within the class of a “sub-Neptune.” Surprisingly, it’s also a massive 23 instances as huge because of the Earth. However, it’s unlikely that the planet is rocky and subsequently liveable; it’s extra probably made of gas, of a form that’s somewhat denser than the atmospheres of both Neptune or Uranus.