City-Block-Size Asteroid 2005 YU55 to Buzz by Earth Today   
   By Mike Wall, SPACE.com Senior Writer   
   Space.com | SPACE.com - 1 hr 41 mins ago....   
       
   Fri, Nov 4, 2011...See more photos from science ¯....An asteroid the size of a   
   city block will zoom by Earth inside the orbit of the moon today (Nov. 8), but   
   it poses no danger of smashing into our planet, scientists say.   
       
   The asteroid 2005 YU55, which is about 1,300 feet (400 meters) across, will   
   make its closest approach to Earth at 6:28 p.m. EST (2328 GMT) today. At that   
   point, the space rock will be traveling at about 29,000 mph and be about   
   201,700 miles (324,600 kilometers) from Earth - closer than the moon, which   
   orbits 238,864 miles (384,499 km) from us on average.   
       
   The flyby will mark the closest such a big space rock has come to Earth since   
   1976. But there's no need to scurry down to the basement bunker to await an   
   asteroid impact, researchers say.   
       
   "2005 YU55 cannot hit Earth, at least over the interval that we can compute   
   the motion reliably, which extends for several hundred years," research   
   scientist Lance Benner, of NASA's Jet Propulsion Laboratory (JPL) in Pasadena,   
   Calif., said in a recent NASA video. [Photos: Asteroid 2005 YU55 Flyby of   
   Earth]   
       
   Studying the space rock   
       
   Researchers are excited about 2005 YU55's close approach, because it gives   
   them a chance to study the space rock as never before. The asteroid was   
   discovered in 2005 by astronomer Robert McMillan of the University of   
   Arizona's Lunar and Planetary Laboratory.   
       
   "When you look through a telescope, asteroids don't look any different from   
   stars," McMillan said in a statement. "The only difference is that they're   
   moving, and to detect that motion we have to take a series of images. Usually   
   we take three images spaced 20 or 30 minutes apart."   
       
   Radar images of the asteroid were taken when it made a previous flyby of Earth   
   in April 2010 (it makes one trip around the sun every 15 months), but this   
   approach will be much closer, so the views will be much better.   
       
   Scientists have already begun taking the space rock's measure using a variety   
   of instruments, including the huge Arecibo radio telescope in Puerto Rico and   
   NASA's 230-foot (70-m) Goldstone radar antenna in the California desert.   
       
   The Goldstone telescope has new imaging capabilities that should shed   
   particular light on 2005 YU55, Benner said.   
       
   "It shows us how big it is, it can show us features on the asteroid, it can   
   tell us information about the asteroid's rotation period," he said in the   
   video. "We should be able to tell much better with these new observations that   
   we're going to do."   
       
   Even those of us without access to the world's biggest radio telescopes still   
   have a chance to spot 2005 YU55 as it zips past Earth. The asteroid will be   
   brightest in the sky a few hours after its closest approach and should be   
   visible with decent equipment under clear, dark skies, experts say.   
       
   "You should be able to spot the asteroid with your telescope if it has an   
   aperture of at least 6 to 8 inches," Alan MacRobert of Sky & Telescope   
   magazine said in a statement.   
       
   2005 YU55 will move quickly, covering about 70 degrees of sky in just 10 hours   
   or so, according to Sky & Telescope. (Your clenched fist held at arm's length   
   measures about 10 degrees.) It will also be relatively dim, so skywatchers   
   will probably need some help to find the space rock.   
       
   But help is out there. The asteroid's coordinates at any given time can be   
   looked up at JPL's Solar System Dynamics website, which is found here:   
   http://ssd.jpl.nasa.gov/.   
       
   Note: If you snap a photo of asteroid 2005 YU55 during its Nov. 8 flyby of   
   Earth and would like to share it with SPACE.com for a possible story or photo   
   gallery, send the image and your observing comments to SPACE.com senior writer   
   Mike Wall at mwall@space.com.   
       
   You can follow SPACE.com senior writer Mike Wall on Twitter: @michaeldwall.   
   Follow SPACE.com for the latest in space science and exploration news on   
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   Regards,   
       
   Roger   
      
   --- D'Bridge 3.64   
    * Origin: NCS BBS (1:3828/7)