A multinational group of astronomers has detected four possible alien worlds circling tau Ceti, which is less than 12 light-years from our Solar System.

Tau Ceti is a Sun-like star located just 11.9 light-years away, in the constellation Cetus.

Also known as 52 Ceti, HD 10700 and HIP 8102, the star is very similar to our Sun in its size and brightness, but it is not as active as the Sun.

In 2012, University of Hertfordshire astronomer Dr. Mikko Tuomi and co-authors announced the discovery of five potential planets in the tau Ceti system, labeled tau Ceti b, c, d, e and f.

In a new study, the same team confirmed the existence of tau Ceti e and f and detected two completely new planets, tau Ceti g and h.

“We came up with an ingenious way of telling the difference between signals caused by planets and those caused by a star’s activity,” Dr. Tuomi explained.