Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
×
Space Science

Asteroid Will Make Close Pass To Earth 119

The Bad Astronomer writes "News is starting to spread about a small 45-meter-wide asteroid called 2012 DA14 that will make a close pass to Earth on February 15, 2013. However, some of these articles are claiming it has 'a good chance' of impacting the Earth. This is simply incorrect; the odds of an impact next year are essentially zero. Farther in the future the odds are unclear; another near pass may occur in 2020, but right now the uncertainties in the asteroid's orbit are too large to know much about that. More observations of DA14 are being made, and we should have better information about future encounters soon."
This discussion has been archived. No new comments can be posted.

Asteroid Will Make Close Pass To Earth

Comments Filter:
  • by Anonymous Coward

    Would any of that thing even reach the ground before burning out during atmospheric entry?

    • by JordanH ( 75307 )

      IANAA (Astrophysicist), but I believe asteroids of that size would reach the earth. Depending what it's made of, it could break into a lot of pieces, though.

      This is a pretty small asteroid and (again, I'm no expert) but its orbit means that it wouldn't have a great relative velocity if it did strike earth (nothing like a comet, by comparison). There were some estimates on the damage it would do if it were to strike in the referenced article and this doesn't seem to be a major concern.

    • Re:45 meters? (Score:5, Interesting)

      by KingofSpades ( 874684 ) on Sunday March 04, 2012 @06:48PM (#39242815)

      What do you think of this [wikipedia.org] ?
      It was made made by a 45 meter impactor.
      Yes, A 45 METER IMPACTOR.

    • Yes, depending what it is made of. Check out this one at the American Museum of Natural History:

      http://farm3.static.flickr.com/2189/2106429655_9edb74118a.jpg [flickr.com]

      The Earth's atmosphere is equivalent to 10.3 meters of water in mass per area. Re-entry heating gets split between the meteorite and the air it is traveling through. When the meteorite mass per area is higher than the equivalent mass per area of the atmosphere, it tends to not pick up enough heat to melt entirely or drag to stop. Asteroid density va

    • Re:45 meters? (Score:4, Informative)

      by Solandri ( 704621 ) on Sunday March 04, 2012 @07:22PM (#39243013)
      The asteroid which made Meteor Crater [wikipedia.org] in Arizona is estimated to have been about 50 meters across. About half of it is thought to have burned up before impact.
      • So does that mean it was about 50 meters across in space, or about 50 meters across when it slammed into the earth?

        • Doesn't really matter. If half its mass ablated away, a rock 50m in diameter would be 40m in diameter at impact. 0.5^(1/3) = 0.7937, or half the mass = 79.4% the original diameter.
  • by NoZart ( 961808 ) on Sunday March 04, 2012 @05:00PM (#39242155)

    Seeing more and more reports of near passes. Frigging Bugs must be out of target practice and are homing in on us! Get NPH!

  • by NoobixCube ( 1133473 ) on Sunday March 04, 2012 @05:01PM (#39242161) Journal

    The world ends toward the end of this year, duh! Of course the chance of hitting the Earth is 0%, because we won't be here!

    • by Xtifr ( 1323 ) on Sunday March 04, 2012 @06:26PM (#39242671) Homepage

      I think you misunderstand the disaster that's coming. When the Mayan calendar ends, all computers that use the Mayan calendar will crash, world-wide. Worse yet, unlike Y2K, where we were able to drag old Cobol programmers out of retirement to fix the problem, experts in Mayan computers are all extinct. So we're all doomed! Except for those of us who don't use Mayan computers. :)

      • So all those old iMacs will crash?
      • by gtall ( 79522 )

        No, that isn't it. The disaster will be all the TV shows predicting disaster will go away, I love those. Worse, Giorgio Tsoukalos' hair will expand to the size of small planet and then catch on fire. It will be a holocaust of immense proportions. I'm looking forward to a gonzo-whopper of a End-O-the-Hair Moronic Convergence.

    • I'm sure someone (not me) will re-analyze the Mayan calendar and show that it's a couple months off..and Mayan doomsday is actually scheduled for 15 Feb 2013.

      BTW, the location of the Chicxulub crater is at the northern edge of Maya-land, although the only Mayans around then were dinosaurs.

    • by kryliss ( 72493 )

      There have been around 514 leap years since it was created around 45 BC. Without the extra days every 4 years and all the adjustments that needed to be done to figure out leap years in the early days plus the Gregorian reform, today would be somewhere in the realm of July or August of 2013. So the 2012 thing should have happened several months ago.

  • by Anonymous Coward

    The odds of any individual item hitting us are (pardon me) astoromically small. Even if it did have a "good chance" of hitting us, that would mean maybe 1% at this point. Obviosly rocks have hit earth before, and rocks will hit earth again, but I'm not going to lose any sleep over it.

  • by Anonymous Coward on Sunday March 04, 2012 @05:09PM (#39242205)

    TFA contains a link to an predicted impact table [nasa.gov] of DA14 with earth, going some 50 years into the future. The likelihood of each impact is rather small, and the cumulative probability of any impact is computed as 2.2e-04 (about 1 in 5000 - not alarming, but not exactly negligible IMO).

    Here's what I don't understand: the first entry in the chart, corresponding to the next risk event, is in the year 2020. What happened to Feb 2013?

    • Mm, yes the reality is that our ability to discover and track these rocks is pretty limited. Our civilisation could be destroyed tomorrow and the first thing anyone would know about it would be when their clothes lit on fire.

      • This is quite wrong. The smaller ones are hard to track, but anything big enough to be civilization destroying is much easier to spot. Typical estimates is 5+ years or more warning.
    • Re: (Score:3, Informative)

      by jaa101 ( 627731 )

      Since we can predict the next (2013) close approach very accurately we're very confident it will be a miss. Therefore that approach doesn't rate a mention in the table.

      The trouble comes in that, while we know the 2013 approach distance will be greater than 0km from the surface (>6400km from the centre) there's still some uncertainty. The earth is massive and the close approach will cause a relatively large change in the orbit of DA14. The size of the change is inversely proportional to the square of t

  • by Anonymous Coward

    Whether the asteroid has a "good chance" of hitting the earth depends on how you define "good chance," which does not have an accepted standard definition.

  • by butilikethecookie ( 2566015 ) on Sunday March 04, 2012 @05:31PM (#39242331)
    What's up with all of these close passes? Hey universe! Grow some nuts and actually hit us with one, you pussy!
    • Yeah, it's such a tease. It's like a hot girl waving at you at a bar, and then you realize she's waving at a guy behind you.

      I say enough with the tease. No more close passes. Either hit this, or go away.

  • by sociocapitalist ( 2471722 ) on Sunday March 04, 2012 @06:24PM (#39242661)

    Asteroid Will Make Close Pass To Earth != "the odds of an impact next year are essentially zero"

  • Sounds like not enough for me to care.
  • NASA places the odds at 99.9988% chance of a miss. That is almost, but not quite, 5-nines. With all the downtime I've seen from companies promising 5-nines of reliability and failing, I'm more than a little skeptical.

  • The number of asteroids passing close to the Earth has not changed recently, but the number we know about has increased dramatically. The current statistics are around 8700 known NEO's, which is double what we knew about 5.5 years ago, 4 times that of 9.5 years ago, and 10 times that of 12.5 years ago. Therefore the number of *known* close passes will continue to go up.

    In the silver lining department, the more NEO's we know about, the more chances for space mining, and the better chance we have of prevent

  • 45m would be roughly comparable to Tunguska. It could completely fuck up a large metropolitan area, but only with a direct hit on land. Otherwise all you get is a sizeable earthquake and possibly a tsunami, which sucks, but is nothing we haven't seen several times in the last decade.

    The point is that it would be a big explosion, but even at its most devastating it wouldn't come close to an extinction event.

    • If it hit the ocean the equivalent volume of water would be displaced, and quite a bit of it would be vaporized. So I would argue that the result would be a significant tsunami (bigger than Japan? I don't know) and a change in the weather for a year or two.

      • Not even close. It wouldn't change the weather at all on the scale of days. The energy needed for a tsunami like the one that hit Japan just short of a year ago requires enormous amounts of energy. The thing is that the earth is really really big, and even though this rock is moving pretty fast, its not that fast, and its not that big. It is comparable to nuclear weapons that have been tested, these did not change weather or produce "significant" tsunami's. At lest not at the scale you are thinking of.
        • Someone in an earlier comment pointed out that the Barringer Crater was thought to have been made by a rock about 55 meters in diameter. I was extrapolating from that. That crater is substantially bigger than anything humans have managed including fusion bombs. But It's an arguable point, especially since I'm too lazy to do any of the math. :)

          • Fusion bombs have (almost) all been air-bursts or fully contained underground tests, and for good reason: the 100-kiloton Sedan [wikipedia.org] nuclear excavation test of Operation Plowshare [wikipedia.org] was responsible for 7% of all radioactive contamination from US nuclear testing.

            • I just saw a picture of the concrete dome built over a Cactus Crater [artificialowl.net] recently ( this is a different picture). That dome is 107m (390 feet) in diameter. The Castle Bravo test left a crater over a mile (2000 meters) in diameter and 250 feet (75 meters) deep. I also found this article [rense.com] that notes that some of the nuclear tests caused tsunamis hundreds of miles away on Christmas and Pitcairn islands. Some of those tests were as 'small' as 16 kilotons. But a 1996 analysis said that tsunamis from underwater

  • The risk, for this asteroid as has been pointed out before is negligible. Anyone who follows http://www.spaceweather.com/ knows 2 or 3 times a year some small piece of rock comes between the earth and moon. Furthermore a few 10 MT nukes can easily either vaporize or at the very least break up into many small pieced a 150 foot chunk of rock. The technology to deliver such a device millions of miles out has been already proven by the recent asteroid and comet intercept probes. A single MIRV, attached to
  • Its been awhile, but I thought there was a game where one could discover the requirements for moving an Asteroid.
  • ...I was wrong when I once said that all the crazy people should be let out of the hospitals and let to run the governments of the US. Nope, it is now very clear that the crazy people should be kept locked up, and furthermore should not be allowed to read the news or anything above their education levels. I mean...I really think that "Interpretation 101" should be elected as a required course, starting in elementary school. Because it is again, very clear, that people should not be allowed to interpret any
  • Attention all non-scientists:

    Watching the movie Armageddon does NOT make you a fucking expert in the subject of Near-Earth Asteroids. Like the newer article on the site has indicated, you know nothing about the subject and are incapable of even recognizing those who do.

  • DA-14 named Apophis http://asteroidapophis.com/year-2013/ [asteroidapophis.com] And it is expected to potentially hit in 2036. Emphasis on potentially.
  • on the premise that we have accurately predicted a large asteroid impact on Earth in a decade from now. Film follows the effect this has on people all over the world, from the time of the announcement to the impact itself. From those who don't believe, to those who look forward to it or see it as the holy Armageddon they've been waiting for. The scary thing is many Christians do look forward to that!

    Would make an interesting film I think.

"The following is not for the weak of heart or Fundamentalists." -- Dave Barry

Working...