On 30 June 1908, an asteroid exploded over Tunguska, Siberia. Asteroids are common. Large asteroids impacting Earth are much less common (thank goodness!), but they do happen. And they can be very, very bad — just ask the dinosaurs. Or ask the folks in Chelyabinsk, Russia who were hurt by flying glass when their windows blew out on 15 February 2013. On Thursday, World Asteroid Day is an attempt to bring attention to this preventable problem.
If you want to get up to speed in a couple minutes, watch this short video interview of billionaire genius Nathan Myhrvold on CNN’s Fareed Zakaria GPS.
If you really want to wade into the debate, you’ll see that Myhrvold and NASA have differences of opinions on how to detect potential Earth-smacking space rocks.
And if you just want to come up to speed on what NASA is doing, you can start with the NEOWISE mission.