Exoplanet around Alpha Centauri is nearest-ever Astronomers have
found the nearest planet outside our Solar System, circling one
of the stars of Alpha Centauri just four light-years away. The
planet has at minimum the same mass as Earth, but circles its
star far closer than Mercury orbits our Sun. It is therefore
outside the "habitable zone" denoting the possibility of life,
as the researchers report in Nature. However, studies on
exoplanets increasingly show that a star with one planet is
likely to have several. At the very least, the work answers the
question first posed in ancient times about planets around our
nearest stellar neighbours. The closest star to the Sun is
Proxima Centauri, which is believed to be part of a three-star
system that includes the brighter stars Alpha Centauri A and B.
The planet was found near Alpha Centauri B by the Harps
instrument at the European Southern Observatory's La Silla
facility in Chile. That puts it far closer to Earth than any of
the more than 840 confirmed exoplanet