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Newfound asteroid will pass by Earth at lunar distance Thursday

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Asteroid close approach EarthA freshly discovered asteroid, roughly as long as a tennis court, will zoom past Earth at about the distance of the moon Thursday, according to NASA. The space rock, called 2010 GA6, was first observed Monday by the Catalina Sky Survey, a telescope project in Arizona that seeks out near-Earth asteroids and comets. 2010 GA6 will make its closest approach to Earth, at a distance about 430,000 kilometers, at 10:06 P.M. Eastern Daylight Time.

The proximity of 2010 GA6′s approach is not unique; in 2010 three other asteroids have come as close or closer to Earth. But the newfound visitor is the brightest asteroid, and consequently among the largest, to draw so near in the past year. Its brightness indicates an approximate diameter of 20 to 40 meters; the next brightest to pass at or within lunar distance in that time span was 2009 JL2, an asteroid about 17 to 37 meters across, in May 2009.

It is not unusual that 2010 GA6 was discovered so soon before reaching Earth’s vicinity; asteroids that small are difficult to spot at great distances. No other approaches of lunar distance or closer are known to be imminent in the next year, despite the fact that they occur every month or so. In other words, plenty of asteroids are headed this way—they simply have not been spotted yet, and asteroid watchers are more focused on the larger objects that pose greater threats to life.

In 1998 Congress charged NASA with finding kilometer-size and larger asteroids that draw close to Earth. A good portion of that population has now been catalogued, and the scope of the survey has since expanded to include objects down to 140 meters in diameter, only a fraction of which have been found. Even smaller objects of the 2010 GA6 variety probably number in the millions, and they could still do significant local damage with an impact. There is a roughly 50 percent chance of a 30-meter-plus asteroid striking Earth each century, according to Clark Chapman, a space scientist at the Southwest Research Institute in Boulder, Colo. Chapman told ScientificAmerican.com in 2009 that such an asteroid impact would cause a multimegaton atmospheric explosion over Earth’s surface, rather than impacting it. "It could be quite damaging (and even lethal) out to distances of 10 to 20 kilometers in all directions if it happened over a populated region with weak structures," Chapman said.

Orbit diagram of 2010 GA6 (blue dot) and Earth (green dot): NASA

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  1. 1. Nightwing861 5:05 pm 04/8/2010

    I heard 2010 GA6 was coming around at 7:06 pm EDT.

    Link to this
  2. 2. Nightwing861 5:12 pm 04/8/2010

    That means that Asteroid 2010 GA6 will come round about 45,597 kilometers distance farther than the moon is to the earth. What are the chances it could impact the moon?

    Link to this
  3. 3. jctvc2000 5:20 pm 04/8/2010

    Where in the sky would we need to look to see this asteroid?

    Link to this
  4. 4. candide 5:25 pm 04/8/2010

    Yes – so did I, 4:06 pm Pacific, 23:06 UTC .

    Link to this
  5. 5. Nightwing861 5:27 pm 04/8/2010

    Something is amiss. The UPI news agency is quoting that Asteroid 2010 GA6 will be flying at a distance of 223,000 miles from earth at its closest pass. That would mean a distance closer to the earth than the moon is, of approximately 15,857 miles. So it will be flying by at around that distance from the moon. Who is the best source for accuracy?

    Small asteroid to zip near Earth on Thursday

    (AP) – 4 hours ago

    PASADENA, Calif. — NASA says a newly discovered asteroid will whiz harmlessly past Earth on Thursday.

    The asteroid dubbed 2010 GA6 will safely fly by the planet shortly after 4 p.m. PDT.

    At the time of its closest pass, the 71-foot-wide space rock will be 223,000 miles away from Earth. That’s about 16,000 miles closer than the moon.

    NASA routinely tracks asteroids and comets that make close approaches to Earth. In January, another small asteroid made an even closer approach to Earth, passing within 76,000 miles.

    Copyright © 2010 The Associated Press. All rights reserved.

    Link to this
  6. 6. candide 5:33 pm 04/8/2010

    "Who is the best source for accuracy? "

    Maybe NASA?
    http://www.nasa.gov/topics/solarsystem/features/neo20100406.html

    Updated April 08, 2010

    With additional observations coming in, scientists at NASA’s Near-Earth Object Office at the Jet Propulsion Laboratory in Pasadena, Calif. have been able to further refine the trajectory estimate for the orbit of asteroid 2010 GA6. This latest trajectory indicates that the closest approach for asteroid 2010 GA6 will be just slightly beyond the moon’s orbit, about 434,000 kilometers (270,000 miles) from Earth. The time of closest approach will be 7:06 p.m. Pacific Daylight Time on April 8 (2:06 U.T.C. on April 9).

    A newly discovered asteroid, 2010 GA6, will safely fly by Earth this Thursday at 4:06 p.m. Pacific (23:06 U.T.C.). At time of closest approach 2010 GA6 will be about 359,000 kilometers (223,000 miles) away from Earth – about 9/10ths the distance to the moon. The asteroid, approximately 22 meters (71 feet) wide, was discovered by the Catalina Sky Survey, Tucson, Az.

    "Fly bys of near-Earth objects within the moon’s orbit occur every few weeks," said Don Yeomans of NASA’s Near-Earth Object Office at the Jet Propulsion Laboratory in Pasadena, Calif.

    NASA detects and tracks asteroids and comets passing close to Earth using both ground and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and plots their orbits to determine if any could be potentially hazardous to our planet.

    JPL manages the Near-Earth Object Program Office for NASA’s Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. Cornell University, Ithaca, N.Y., operates the Arecibo Observatory under a cooperative agreement with the National Science Foundation in Arlington, Va.

    For more information about asteroids and near-Earth objects, visit:

    http://www.jpl.nasa.gov/asteroidwatch

    Link to this
  7. 7. Nightwing861 6:11 pm 04/8/2010

    According to Richard Kowalski, of the Catalina Sky Survey
    Lunar and Planetary Laboratory, University of Arizona
    you can find the coordinates of 2010 GA6 here:

    http://www.minorplanetcenter.org/iau/MPEph/MPEph.html

    In the box, type in 2010 GA6 or whatever you are trying to track, and then click "Get ephemerides/HTML page above that. Ephemerides is another name for a table of values that gives the positions of astronomical objects in the sky at a given time or times.

    http://www.lpl.arizona.edu/css/

    Link to this
  8. 8. Nightwing861 6:21 pm 04/8/2010

    When I go to that link:
    http://www.jpl.nasa.gov/asteroidwatch

    It gives the time it will be passing by earth as 4:06 pm Pacific time, and at another link:

    http://www.nasa.gov/topics/solarsystem/features/neo20100406.html

    it gives the earth flyby time as 7:06 pm Pacific time

    both articles are updates by NASA.

    So, some time between 7:06 pm and 10:06 pm eastern daylight time?

    You won’t be able to see it with the naked eye. Once you get the coordinates from the ephemerides link I provided, a person with access to a powerful telescope would be able to see it, I would imagine. Any takers?

    Link to this
  9. 9. jtdwyer 6:23 pm 04/8/2010

    So does anyone know offhand why this object apparently won’t be hitting the moon? Thanks in advance.

    Link to this
  10. 10. Nightwing861 6:38 pm 04/8/2010

    This NASA website that was updated today lists the 9th as the flyby date of Asteroid 2010 GA6:

    http://neo.jpl.nasa.gov/ca/

    Hmm.

    It’s in the second of two graphs. Click on the 2010 GA6
    on that graph and you get a really awesome 3-D map and
    to the right you can manipulate it from different angles
    by moving the right bar up and down.

    Last post from me today. My work here is done.

    I am going to toast one to 2010 GA6, where ere it may roam, keep it the heck away from my home!

    Link to this
  11. 11. lowndesw 10:24 pm 04/8/2010

    You again, jtdwyer?? The official reason why 2010GA6 did not hit the moon is because it missed it.

    Sorry.

    Link to this
  12. 12. Herschel 10:58 pm 04/8/2010

    @jtdwyer: assuming the closest approach figure of 270,000 miles from Earth is correct, the object will pass some 30,000 miles outside the orbit of the Moon. Even if 2010 GA6 were passing by us at 240,000 miles, the chances of it hitting the Moon would be slight.

    Link to this
  13. 13. jtdwyer 11:41 pm 04/8/2010

    Herschel – Thanks. I kind of figured it might be passing at a similar distance from the Earth as the moon, but not really near the moon. I’m just a passerby myself and can’t do the math, but the actual path of an asteroid must be determined by not only its ballistic trajectory in its orbit around the Sun but the gravitational influences of the Earth and Moon as well. I’d think the Earth, at this distance, would primarily influence the trajectory of this small body object but that it might even collide with the moon if they happened to be nearby at that moment. I’m sure NASA has done all the math: just curious – thanks.

    Link to this
  14. 14. jack.123 5:47 am 04/10/2010

    jtdwyer,go to the jpl near Earth object site,and you should be able to determine the path of 2010GA6 then locate the position of the moon,I would suppose that if it were going to be close the would be alot talk about it,

    Link to this
  15. 15. jtdwyer 6:40 am 04/10/2010

    jack.123 – Thanks. The only posting I found was low res illustration, not even depicting the moon’s location. The description posted Thu. did say that the flyby would be 3 hours later and 50K miles (~25%) further away than previously expected, at 270k mi. – just slightly beyond the moon’s orbit. Makes one glad the estimates were off in that direction, presuming this is not some postmortem dream state…

    Link to this
  16. 16. frankboase 8:49 pm 04/10/2010

    How can anyone say of asteroids that," A good portion of that population has now been catalogued," when obviously we don’t know the total "population"

    Link to this
  17. 17. jtdwyer 3:45 am 04/11/2010

    frankboase – Yeah! Kinda like determining that a mass extinction is underway even though maybe only 25% of species have been identified…

    Link to this
  18. 18. frankboase 3:26 am 04/13/2010

    Think that may be a bit more obvious,ok we may not have found the last creepy-crawly,but l think we have most proably found all the,for example elephants.
    (But not all the lizards!!)

    Link to this
  19. 19. eco-steve 7:34 pm 04/18/2010

    David Cota : My wife and I saw an asteroid ricochet off the upper atmophere above France in 1975. It crossed the entire night sky in around two to three seconds. Where it ricocheted a huge cloud of yellow-green light grew bright enough to read a newspaper for fifteen minutes in a moonless midnight sky. The object covered about three degrees of sky, made no sound and span rapidly as it headed off into deep space. We reported this to astronomers who estimated the object’s size as being around ten miles diameter. It is unclear where it is now. A close shave!

    Link to this

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