A super-Earth has been discovered orbiting in the ‘zona habitable‘ from a red dwarf star 137 light years away.
The system could also host a second planet the size of the Tierra.
Called TOI-715 b, the super-Earth is about one and a half times wider than Earth.
It orbits at the distance from the star that could give the planet the right temperature for liquid water to form on its surface.
The smallest planet could be only slightly larger than Earth and could also live just inside the habitable zone.
This discovery was made possible thanks to data from NASA’s TESS exoplanet hunter, analyzed by scientists led by Georgina Dransfield of the University of Birmingham who published results in the journal Monthly Notices of the Royal Astronomical Society.
According to NASA, TOI-715 b could be making its appearance at just the right time.
Its parent star is a red dwarf, smaller and cooler than our Sun; Several of these stars are known to host small rocky worlds.
At the moment, they are the best bet for finding habitable planets.
These planets have much closer orbits than those that surround stars like ours. Solbut because red dwarfs are smaller and cooler, the planets can be clustered closer together and still be safely within the star’s habitable zone.
Narrower orbits also mean that those that cross the faces of their stars (that is, when viewed with our space telescopes) intersect much more frequently.
A planet to live on?
In the case of planet b, that’s once every 19 days, a “year” on this strange world. Therefore, these star-crossing (“transiting”) planets can be detected more easily and observed more frequently.
Planet TOI-175 b is on the list of habitable zone planets that could be examined more closely by the Webb telescope, perhaps even for signs of an atmosphere.
Much will depend on other properties of the planet, including its mass and whether it can be classified as a “water world,” making its atmosphere, if present, more prominent and much less difficult to detect than that of a more massive planet and dense and drier, it will likely keep its lower-profile atmosphere closer to the surface, NASA adds in a statement.
If the possible second planet of the system is also confirmed, the size of the Tierra, would become the smallest habitable zone planet discovered by TESS so far. The discovery also exceeded TESS’s initial expectations by finding an Earth-sized world in the habitable zone.