"Space rocks visiting Earth like this are rare. Described as mini-moons, the only other time that one graced our planet (that we know about) was in 2006. A tiny asteroid, measuring a couple of meters in diameter and known as 2006 RH120 was also discovered by folks working at the Catalina Sky Survey."
Presumably it's ruddy hard to spot them though, particularly given they don't stay for long, so do we know how rare or not it is?
Biting the hand that feeds IT
