Now that this planet appears to be a real world, Teske says that there are many unanswered questions she hopes to resolve quickly, such as what the surface is made of, or if it has an atmosphere. One thing astronomers are confident about, though, is that this new planet is not habitable. It orbits too far from its parent star to get enough warmth for liquid water on its surface.
These questions could be answered by a future instrument that could take direct images of close-up planets, such as NASA’s Wide Field Infrared Survey Telescope (WFIRST) telescope, which is slated to launch in the 2020s. (The project is in some flux since the Trump administration requested its cancellation in NASA’s 2019 budget, but the telescope work continues under a spending bill.)
Teske said that there are hints that there might be another planet around Barnard’s Star, although it’s difficult to determine if the signal that investigators saw is from the star itself or from another planet. The European Space Agency’s Gaia mission could eventually shed light on this question, since the spacecraft is designed to precisely track the movements of stars.
Finding a planet near Barnard’s Star shows the value of combining a bunch of datasets on planet searching, something that is already ongoing with the Red Dots campaign, whose goal is to find terrestrial planets at stars nearby our own sun.
“I hope we can contribute to more discoveries like this — small planets around nearby stars,” Teske said, “to ultimately help answer the question, how unique is Earth?”