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Earth may get hit tommorow

  1. Oct 6, 2008 #1


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    It's being reported in the minor planet mailing list that Sudan will be hit tommorow by an object not large enough to cause any damage. But this may be the first instance of an impact being predicted at all.

    This image was generated with Gravity Simulator, using data from JPL Horizons and http://www.cfa.harvard.edu/mpec/K08/K08T50.html. It shows an impact at 02:48:12 with the bolide colliding with Earth at a speed of 12.851 km/s
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  3. Oct 6, 2008 #2
    its still big news even thoughit probably wont cause much damage. nice data collection stuff....
  4. Oct 6, 2008 #3


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    Whoa. That's a pretty big step in identifying these kinds of objects and predicting impacts. We'll find out tomorrow if it actually hits, I suppose!
  5. Oct 6, 2008 #4


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    Thats pretty awesome that they have been able to detect this object and with an entire day beforehand! Considering there are so much space to monitor :smile:
  6. Oct 6, 2008 #5
    Here's JPL's page mentioning a location...
  7. Oct 6, 2008 #6


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    I bet they were planning for a much bigger press reaction, with lots of end of the world media stories to deny!

    You have to feel sorry for the rock, for 4.5Billion years it has been floating around waiting for the planets to align to give it it's 15mins of fame. Then because of a bunch of merchant bankers it gets pushed to item 6 in the science section.
  8. Oct 6, 2008 #7


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    Aha! This explains a comic I saw:
  9. Oct 6, 2008 #8
    astronomy is one area where the line between pro/amateur scientists 'blurs', or as some contend does not exist--as the old term 'Naturalist'--amazingly, there are more 'amateurs' scanning for NEOs than the 'pros'--our last Real problem NEO (near earth object), came 'in with the Sun, as any clever 'fighter-pilot', zipped between earth and its moon, and was only detected by amateurs after its relatively near miss. considering velocities of 'space-stuff', minutes, even seconds become notable. why are the public's NEO-spotting efforts so poor? Budget. i may be wrong, but seems NASA's is 1%--our 'defense-budget'? Huge, and who really knows? meanwhile, globally, quite sophisticated 'amateur' gear continues to scan for what may be the next 'Bedout' impact that led to the Permian 'Great-Dying'--are our leaders nutz? what could NASA have done w/the Iraqi-War monies? kill? or perhaps save? we lucked-out on this one, due to its low-angle entry--if it came 'straight-in'? diffy scenario---
  10. Oct 6, 2008 #9
    According to this link, the asteroid is no more than 3 meters in diameter, so there is not much to be concerned about in terms of global catastrophe. Actually, it appears that it will burn up in the atmosphere. Now, if it were a kilometer in diameter, this may be a different story.


    The fact that it was predicted with high certainty is a landmark. Asteroid orbits are difficult to pin down with high precision due to many variables.
  11. Oct 6, 2008 #10


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    Hmm, I always felt the line was defined pretty clearly. I would say astronomy is one field where amateurs make very significant contributions.
  12. Oct 6, 2008 #11


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    Definitely, in the area of supernova detection as well! But there is a very distinct line between amateur and professional, I agree.
  13. Oct 7, 2008 #12
    heres the day! one to remember hopefully for good not bad
  14. Oct 8, 2008 #13


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    Has anybody heard of any observations on this? Do we have confirmation?
  15. Oct 8, 2008 #14
    i got an article on my phone that the meteor burned up in the atmosphere at about three AM over sudan. from the associated p[ress you can probably find it on their site
  16. Oct 8, 2008 #15
    Just a minor note, but Fox made a mistake by saying that 6 feet is about 3 meters. I assume that Fox learned that it was 3 meters and then incorrectly converted it to feet.

    Sorry to be so meticulous. :)
  17. Oct 8, 2008 #16
    I noticed that mistake too. The following link has a quote from the associate director for the Minor Planet Center that suggests the diameter range is 1 to 5 meters.


    I still haven't came across any info regarding its entry and subsequent impact(?). Please let us know if you find something.
  18. Oct 8, 2008 #17
  19. Oct 10, 2008 #18


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    I'm curious if it's possible to figure out what type of object it was from the data we received from the collision.

    All the reports were saying it was coming in at 12.8 km/sec. It released an energy about 1.1 to 2.1 kT of TNT. It was also reported to have been 3 meters across.

    We've got v, we've 1/2*mv2, and we've got the volume. This gives us the density: solve for M and then divide by the volume.

    Presumably this thing is irregular, so a sphere is probably going to be generous. Let's call it spherical and have its energy be the high end of the range (it's more likely to be 1.6 kT with a nonspherical and therefore less massive shape)

    2.1kT = 8.8*1012 J

    mv2 = 1.8*1013 J
    v2 = 128002, which makes

    m = 110000 kg

    Volume = pi*4/3*r3, where r = 1.5: 7780 kg/m3

    Most asteroid densities are g/cm3, which would be 7.8 g/cm3

    That's iron range, isn't it?


    There were also reports about a 1.0kt explosion, which would get us down around 3700 or so (stony)?
  20. Oct 13, 2008 #19
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