Astronomers have discovered one of the closest stars to our Sun, and they say that more undetected close neighbours may be lurking in our vicinity.

The new star was found because its relatively swift motion across the sky was picked up by automated sky surveys.

It ranks as the third closest star system and the fifth closest star to our Sun.

It is a faint red star, a so-called red dwarf, and is only 7.5 light years away.

A dim red dwarf star (Nasa/Esa)

As yet unnamed the new star goes by the designation SO025300.5+165258.