Thursday, March 2

96 years to doomsday?

An asteroid called 2004 VD17 has just been given the second-highest Torino-scale rating ever assigned, a 2 on the 10-point scale. The estimated 580-meter-diameter asteroid has a current probability of one in 1600 of slamming into the Earth on May 4, 2102.
The only other asteroid that ever got a rating higher than 1 on the supposedly Richter-like hazard scale, which combines the likelihood of impact and the extent of its devastation, was 2004 MN4, which was later renamed Apophis. That one briefly, in Dec. 2004, was given one chance in 300 of an impact in March 2029, giving it a Torino rating of 4, which was ruled out after just a few weeks. But Apophis continues to be a potential threat as well, because it will make such a close approach to Earth that year that its orbit might be altered enough to send it on a collision course in 2036.
The possible impact of 2004 VD17 will probably be ruled out quickly as well, as most of them are, as more observations allow the orbit to be pinned down more precisely. And the date is so far away that there would be plenty of time to plan and carry out a mission to nudge it aside long before then. But if it did hit, an object that size, though not a dinosaur killer or civilization destroyer, would produce a 15 gigaton blast, leave a crater 10 kilometers across and pretty much devastate a continent and cause global climatic effects.
There's a good story about it on NewScientistSpace, and the technical details are HERE on NASA-JPL's near Earth impact hazard pages.