Mysterious object seen speeding past sun could be 'visitor from another star system'

If its origins are confirmed, the asteroid or comet, named A/2017 U1, will be the first object known to come from elsewhere in the galaxy, say astronomers

A mysterious object detected hurtling past our sun could be the first space rock traced back to a different solar system, according to astronomers tracking the body.

While other objects have previously been mooted as having interstellar origins, experts say the latest find, an object estimated to be less than 400m in diameter, is the best contender yet.