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Posted by: Proplyd Jul 28 2010, 01:41 PM

http://www.universetoday.com/2010/07/27/researchers-say-asteroid-has-1-in-1000-chance-of-hitting-earth-in-2182/

Spanish asteroid trackers upgraded the chance that asteroid 1999 RQ36 could hit our planet to a one-in-a-thousand chance on Sept. 24, 2182 from one chance in 1,400. Currently, however, NASA assigns it a 1 in 3,570 chance. That is a 99.972% chance the asteroid will completely miss us.

The Spanish team said knowing this asteroid poses a potential twenty-second century threat may spur design asteroid deflection advances. They have estimated and monitored potential impacts for this asteroid through 2200.

In 2009, new calculations and observations revealed a chance of impact sometime during a 30 year span in the mid-to late 2100’s. The asteroid is 560 meters wide, more than twice the size of asteroid Apophis, which has a 1 in 250,000 chance of impact in 2036. The greater width means it will have ten times the impact energy. Gravitational influences on the asteroid when it passes massive objects, plus slight Yarkovsky effects induce a fair amount of orbital uncertainty. This is sunlight hitting one asteroid side and not the other, producing a tiny acceleration.

We have not measured this effect for 1999 RQ36 until this new research. Up until 2060, the divergence of the impacting orbits is moderate. Between 2060 and 2080, it increases 10,000 times as the asteroid approaches Earth. It then increases again slightly until another approach in 2162, and then decreases. The most likely collision year is 2182.

This complex dynamic makes a realistic deflection procedure possible. We can produce a path deviation before the impact in 2080, and more easily before 2060. Discovering this object after 2080 means the deflection would require technology we do not currently have. Therefore, we need careful monitoring to deflect this object type with moderate technological and financial resources.

We call the proposed robotic mission to this asteroid OSIRIS-Rex, the Origins, Spectral Interpretation Resource Identification, and Security, Regolith Explorer. I dare you to say that quickly three times. It is one of three NASA New Frontiers proposals for more study under. The mission would launch in about 2018, and it could provide solar system formation information, and perhaps shed light on how life began. It also might be one of the first looks at how we might deflect an asteroid.

Posted by: StarPilot Jul 28 2010, 02:10 PM

QUOTE (Proplyd @ Jul 28 2010, 03:41 PM)

Posted by: Dewtey Jul 28 2010, 03:31 PM

170 year lead time? If we act NOW, we just might save the Earth.

Posted by: Proplyd Jul 28 2010, 03:45 PM

While the asteroid is large at 1,800 feet across, put that in perspective. The dinosaur killer was probably six miles across, or 30,000 feet. That's 16 times as wide and 5,000 times the impact energy. This asteroid will be bad news for any continent it hits, but it will not end human life.