Earth-sized alien planet gripped by widespread volcanism

An exoplanet called LP 791-18 d, an Earth-size world about 90 light-years away, is seen in an undated artist's rendering. A more massive planet in the system, shown as a small blue dot on the right, exerts a gravitational tug that may result in internal heating and volcanic eruptions, like on Jupiter?s moon Io. NASA Goddard Space Flight Center/Chris Smith (KRBwyle)/Handout via REUTERS

An Earth-sized planet orbiting a dim star in our galactic neighborhood is offering some of the best evidence to date of volcanism beyond our solar system, with observations suggesting a rugged and rocky world tormented by constant eruptions.

Scientists said on Wednesday the planet, the third detected orbiting this particular star, is likely covered with volcanoes - similar to Jupiter's moon Io, the most volcanically active body in our solar system. In our solar system, Earth and Venus are volcanically active, as are some of Jupiter's moons.