Neptune and gassy planets like it may be uninhabitable, but new research suggests they may be able to develop into Earth-like, potentially habitable, planets.
Led by University of Washington (UW) doctoral student Rodrigo Luger and research assistant professor Rory Barnes, authors of a study in the journal Astrobiology detailed these "mini-Neptunes" and how they can make their transition.
"There are many processes that are negligible on Earth but can affect the habitability of M dwarf planets," Luger said in a news release. "Two important ones are strong tidal effects and vigorous stellar activity."
The habitability of a planet has much to do with the host star, as the size and mass of the star will affect the range and size of its habitable zone. Astronomers investigating stars with exoplanets orbiting it, they determine the star's size and mass to see if any planets lie in the habitable zone.
Astronomers often have to look outside the Milky Way Galaxy for such stars because the ones in it, aside from the sun, are M dwarfs with small habitable zones with a short range.
"This is the reason we have ocean tides on Earth, as tidal forces from both the moon and the sun can tug on the oceans, creating a bulge that we experience as a high tide," Luger said. "Luckily, on Earth it's really only the water in the oceans that gets distorted, and only by a few feet. But close-in planets, like those in the habitable zones of M dwarfs, experience much stronger tidal forces.
"The bottom line is that this process - the transformation of a mini-Neptune into an Earthlike world - could be a pathway to the formation of habitable worlds around M dwarf stars."