First 'exomoon' may have been found
Astronomers have announced the possible discovery of the first known moon outside our Solar System. This "exomoon" is not like any in our cosmic neighbourhood: it's the size of Neptune and orbits a planet the size of Jupiter - but with 10 times the mass. The object was spotted in data from Nasa's Kepler spacecraft, and later observed using the Hubble telescope. Astronomers David Kipping and Alex Teachey have published their results in Science Advances journal.