Every one of us contains alien atoms that originated in a galaxy far, far away, a new study suggests. Scientists have discovered that up to half the matter making up our galaxy, the Milky Way, used to belong to other clusters of stars. The sun, the Earth, and even our own bodies probably contain a large proportion of this galaxy-hopping material, which migrated to our part of the universe across vast expanses of space. Lead researcher Dr Daniel Angles-Alcazar, from Northwestern University in the US, said: “Given how much of the matter out of which we formed may have come...