Finding a potentially habitable exoplanet isn’t as easy as you might think. Orbiting at a temperate distance from the host star is just the first step. Size and composition also play a role – as does the level of flare activity in the star. And all of that doesn’t mean much if the system is so far away we can’t take detailed observations to find out if it is habitable.
A newly discovered system looks like it could tick a good number of those boxes. And it’s incredibly close – just 10.7 light-years away from the Solar System. This means it could soon become one of the most studied systems in our local neighbourhood.
“These planets will provide the best possibilities for more detailed studies, including the search for life outside our Solar System,” said astrophysicist Sandra Jeffers of the University of Göttingen in Germany.
The star is called Lacaille 9352, or GJ 887. In its orbit, scientists have found two exoplanets that could be terrestrial – rocky, like Earth and Mars.Tantalisingly, there’s also a hint of a third terrestrial exoplanet orbiting at a greater distance – a distance that could make it temperate, neither too hot nor too cold to prohibit liquid water on the surface.
This hint of the third planet is considered inconclusive at this stage, but the discovery of the two close-orbit planets (and the potential for the third planet) are enough to warrant a much closer look at the GJ 887 system.
The star itself, which is about half the mass of the Sun, is a red dwarf – a type of long-lived, relatively cool, small star – which is the most common type of star in the Milky Way.
We’ve found a lot of exoplanets orbiting red dwarfs; and, because these stars are not…
