Brian May is giving rock fans a quick tutorial on that asteroid that passed within 17,000 miles of Earth Friday.

As you probably know, the Queen guitarist is also a Ph.D in astronomy. So the asteroid fly-by -- and the meteor strike in Russia Friday morning -- have him excited.

He says, "It's called 2012 DA 14 -- and this is a pretty unusual event. The object, an NEO, or Near Earth Object, will be less than 18,000 miles from the Earth at its closest. And it's the brightest of such objects to be seen in our lifetimes. That might seem a long way… but in astronomical terms, that's a hair's breath away from a pretty catastrophic collision. That's closer than our geo-stationary man-made satellites, which handle communications around the world these days, and much closer than moon. So, although there is no cause for alarm this time, there is no room for complacency as far as Earth-strike is concerned. Astronomers have only recently been on the case as far as looking for possibly dangerous objects on a collision course with Earth. So far, the news is good, but nobody is quite sure that we have seen every possible candidate."