|Illustration from NASA|
The science team that made the discovery, led by Guillem Anglada-Escudé of Queen Mary University of London, published its findings today in the journal Nature. The newly discovered planet is at a distance from its star that allows temperatures mild enough for liquid water to pool on its surface. The scientists determined that the new planet, dubbed Proxima b, is at least 1.3 times the mass of Earth. It orbits its star far more closely than Mercury orbits our sun, taking only 11 days to complete a single orbit.
While the new planet lies within the distance at which temperatures are right for liquid water, the so called habitable zone, scientists do not yet know if the planet has an atmosphere. It also orbits a red-dwarf star, far smaller and cooler star than our sun. The scientists believe that the planet likely presents only one face to its star instead of rotating through our familiar days and nights. And Proxima b could be subject to potentially life-extinguishing stellar flares.
Statistical surveys of exoplanets, planets orbiting other stars, by NASA's Kepler space telescope have found a large number of small planets around small stars. Despite the unknowns, the discovery of Proxima b was hailed by the NASA exoplanet hunters as a major milestone on the road to finding other possible life-bearing worlds. According to NASA, the Kepler data suggests there should be at least one potentially habitable, Earth-size planet orbiting M-type stars, like Proxima, within 10 light-years of our solar system.
So the discovery of Proxima b was "not completely unexpected, but nonetheless exciting. Coming generations of space and ground-based telescopes, including large ground telescopes now under construction, could yield more information about the planet, perhaps inspiring ideas on how to pay it a visit.
The discovery of Proxima b might inspire more interstellar research, especially if the planet proves to have an atmosphere. "It may be that the first time we get really good information is from the newer telescopes that may be coming online in a decade or two," said Bill Borucki, now retired, but a former principal investigator for Kepler and an exoplanet pioneer. The Kepler exoplanet has discovered the bulk of the more than 3,300 exoplanets found so far.