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Mars Space Science

Mars Asteroid Impact More Likely Than Before 207

sheldie writes "The probability of asteroid 2007 WD5 impacting Mars has been revised following further observations. The chance of impact has increased from 1.3% to 3.9%" This is a follow-up to earlier coverage of this asteroid from last week.
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Mars Asteroid Impact More Likely Than Before

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  • Wow (Score:4, Funny)

    by snowraver1 ( 1052510 ) on Monday December 31, 2007 @12:08PM (#21866350)
    That would truly be an amazing event. The science that could be learned in the event of a collision would be massive! I, for one, welcome our planet smashing overlord!
    • Re:Wow (Score:4, Funny)

      by Anonymous Coward on Monday December 31, 2007 @01:07PM (#21867066)
      I've experiments to be run. There is research to be done. On the planets who are still alive...
    • It would be amazing! Too bad most of us wouldn't get a good view of it.

      Of course the big thing to worry about is not one hitting Mars, but one from Mars hitting Earth - especially if it lands somewhere near Grover's Mill, New Jersey. (And even worse if the name Yoyodyne is associated with it!)
    • Re: (Score:3, Funny)

      by sm62704 ( 957197 )
      Wow, the slashdot crowd gets younger every year (and I'm so old I was a beta tester for dirt. We never did get all the bugs out).

      Does nobody remember Comet Shoemaker-Levy 9 [] hitting Jupiter in 1994? Hell I even remember that and there was a catastrophe in my home town []... oh wait, no that was 1993. The comet hitting Jupiter was a year later.

      But at any rate, we had a extinction-causing (if it would have happened on Earth) impact in less than the last fifteen years!

      How many collisions do you guys need, anyway?
    • Unfortunately, they don't tell you everything. Sure there's now a 1:25 chance of it striking Mars, but what they don't tell you is that there is 4:1 chance it'll strike somewhere on Mars' darkside. Only those lucky Saturnian Overlords will get a view of it, and we'll have to pay hefty fees for the copyrighted DRMed videos of the impact. And then only on low-def capable viewers. :'(

      We should send some of our ELO defense missiles up there and shove a few more 'roids toward Mars. Hey, if we shoot enough at the
  • by bwintx ( 813768 ) on Monday December 31, 2007 @12:09PM (#21866356)
    "BREAKING NEWS! [SFX: Ridiculously melodramatic sounder]

    "NASA now says an asteroid impact on Mars is now three times more likely than previously thought.

    "At this rate, the impact's likelihood will exceed 150% in just a few days."
    • by Smidge204 ( 605297 ) on Monday December 31, 2007 @12:15PM (#21866442) Journal
      To be fair, a "1 in 24" is much better odds than "1 in 76." So yes, It is three times more likely and yes, that is a pretty big deal.

      A fresh impact crater would reveal all sorts of valuable, once-in-a-lifetime data about the planet that is likely to be the first humans will tred on since Earth. Don't underestimate the science.
      • A fresh impact crater would reveal all sorts of valuable, once-in-a-lifetime data

        Or it could muck up a really good probe, covering the solar panels with dust and forcing it to permanantly power down. Yes, a long shot, but so is the possibility of the thing hitting Mars.
  • by plover ( 150551 ) * on Monday December 31, 2007 @12:09PM (#21866360) Homepage Journal
    C'mon, people, it's our duty as annoying geeks to raise paranoia amongst our friends and family.

    Tell them that if the asteroid just barely misses Mars that its gravitational pull could actually slingshot the rock straight towards earth! You just don't have to tell them what the chances of that are (astronomical would be an accurate value.)

    Lets see how many people who failed math we can get to go hide in caves till it passes. :-)

  • by dattaway ( 3088 ) on Monday December 31, 2007 @12:10PM (#21866380) Homepage Journal
    See that first picture where the arc of the asteroid makes a flyby right into our orbit, while just passing Mars?
  • Versus Jupiter (Score:4, Interesting)

    by us7892 ( 655683 ) on Monday December 31, 2007 @12:12PM (#21866398) Homepage

    How come the experts cannot mathematically say for certain whether this rock will hit Mars? What's the wildcard in this calculation that injects uncertainty?
    • Re: (Score:2, Funny)

      by Anonymous Coward
      They're waiting to see whether or not John McEnroe will volley it back. If he whiffs it we'll still be in for one helluva show, so it's win/win as far as I'm concerned.
    • Re:Versus Jupiter (Score:5, Informative)

      by plover ( 150551 ) * on Monday December 31, 2007 @12:19PM (#21866498) Homepage Journal
      Measurement inaccuracies in the observations of its current trajectory. It's not like we can hold a tape measure up to it and figure out its precise position, or put it on a scale to check its mass.

      The more it moves, however, the higher the precision of the measurements can be. So as time progresses, the astronomers will be able to reduce the circle of uncertainty.

      • Re: (Score:2, Funny)

        by Tablizer ( 95088 )
        The more it moves, however, the higher the precision of the measurements can be. So as time progresses, the astronomers will be able to reduce the circle of uncertainty.

        "The data's in. Let's see, it's going to miss Mars, and on Dec. 31 hit the 3rd pla[NO CARRIER]
      • Re:Versus Jupiter (Score:5, Informative)

        by Markrian ( 931172 ) on Monday December 31, 2007 @12:57PM (#21866946)
        Actually, since the asteroid's mass is negligible to that of the planets, its mass is irrelevant to its trajectory as it can be considered a test particle. We only need to know six pieces of information - three spatial coordinates, and three velocity components. It's easy to measure four of these very accurately, but the radial distance and velocity of the asteroid with respect to us are harder. These are where the majority of the uncertainty comes from.
      • Re: (Score:3, Funny)

        by sm62704 ( 957197 )
        A sig I saw here a few days ago fits that comment (im)perfectly: "I have measured my velcity with such exquisit perfection that I have no idea where I am".

        Ok, so that applies to particles and not astronomy. Fuck up a perfectly good joke...
    • Re: (Score:3, Informative)

      by Anonymous Coward
      Accuracy of measurements, mainly.

      Also, regarding Jupiter and Shoemaker-Levy 9: Jupiter is a much larger target with a much larger gravitational field. In fact, Comet Shoemaker-Levy 9 was actually orbiting Jupiter (not the Sun), and it was easy enough to see that its orbit was decaying. That fact alone means a collision was near certain.
    • Re:Versus Jupiter (Score:5, Insightful)

      by blhack ( 921171 ) on Monday December 31, 2007 @12:27PM (#21866592)
      yes, there is. It is called the:

      "not knowing the exact position, velocity, and mass of the object due to inadequate funding that has been, instead, spent on countless "beautification" projects around major cities uncertainty principal"
      • by Cheapy ( 809643 )
        Looking at the budget of 2007, looks like a good portion of those major cities were in Iraq :)
      • Re: (Score:3, Informative)

        by sm62704 ( 957197 )
        Yeah, blame OUR government! Like there aren't any other governments, or like Europe doesn't have a space agency, or China, or Russia. Or like ours is the ONLY inefficient government.

        I mean, my government (with the best legislators money can buy) really sucks, but it's not like any of the others do such a great job, either. Maybe ours sucks worst but they all suck.
    • What's the wildcard in this calculation that injects uncertainty?

      It's small size. It's diameter is only 30m.
    • by Cally ( 10873 )
      The uncertainty is because the object's orbit has only been loosely constrained. IIRC there have only been two or three "prediscovery" images and a similar number afterwards. Google up the equations of orbital motion and bend your brain a little with the level of postitional uncertainty over an orbit that goes out to Neptune when you only have positions for the object covering a few weeks.
    • by anethema ( 99553 )
      Well other than the obvious difficulty in even knowing its exact trajectory...

      I imagine the problem might have something to do with the Three body problem. []

      Once 2 gravitational fields are affecting and object plus its own, it is, as far as I know, Impossible to predict its path. Even if all variables are known.
      • It's not impossible, there is a rapidly converging series that approximates it. But there is no general and nice closed form solution.
    • Re: (Score:3, Informative)

      by Jeff DeMaagd ( 2015 )
      From the tone in the question, I would guess that you've never taken a proper science class.

      The basic point with scientific measurement is that you can take measurements, but you need to have realistic expectations as to the accuracy of those measurements and retain the error bounds throughout the calculations. For example, 1cm read from an ordinary ruler shouldn't be taken as 1.00000000000000 cm. It should be taken as something like 1cm plus or minus 0.05 cm. That's a possible error bound of plus or min
  • It's a space station!
    • by sm62704 ( 957197 )
      Thank God for that! I'd rather be mooned [] than to be hit by an Asstroid [].


      (latest journal is a letter from a prison inmate)
  • ... and... there. We need to put 3 x as much armor on the new rover. Done. Next?

  • Oh god! We're all gonna die!

    Wait, what?
    Oh. Never mind.
  • by ToSeek ( 529348 ) on Monday December 31, 2007 @12:22PM (#21866532)
    As the Bad Astronomer notes [], the odds of nothing happening have shrunk from 99% to 96%.
  • by Will_Malverson ( 105796 ) on Monday December 31, 2007 @12:23PM (#21866558) Journal
    Remember how these things work - they made a few observations, from which they made a cone through which they're 95% (or whatever) sure that the asteroid will pass. Mars filled up about 1.3% of that cone, and so they can say that there's a 1.3% chance that Mars will be hit by the asteroid.

    A few days later, with better observations, the cone shrinks, and now Mars takes up 3.9% of the cone. As the cone shrinks, Mars will continue to consume a larger and larger portion of it, right up until the time (maybe) that the cone shrinks outside of Mars and they determine that there will be no impact.

    So remember, this is not unusual, and *every* non-impact event follows this pattern: Scientists find potential impact. Impact probability increases. Impact probability increases. (maybe a few more repetitions, too) Suddenly, they decide that it's not going to hit, and impact probability goes to zero.
    • Very similar to the National Weather service predictions of how many hurricanes are going to happen this year and where they will hit once they actually form. Until it actually hits they don't know for sure just where they will land.
  • by WormholeFiend ( 674934 ) on Monday December 31, 2007 @12:27PM (#21866586)
    from Klendathu? /Service guarantees citizenship //Would you like to know more?
  • That is (roughly) the size of the current transverse error ellipse at the closest approach to Mars, so statistically the Asteroid should pass at least that close to Mars.

    (Mars's volumetric radius is 3389.5 km, and 3.9 % probability of impact roughly means that the error ellipse is 1 / 0.039 ~ 25 times the projected area of Mars at the time of closet approach. This ignores gravitational focusing, but this is not too important for Mars.)

    So, based on the current error ellipse, not only could it hit Mars, it co
    • Having RTFA, the error ellipse is not nearly circular - there is a very narrow ellipsoid that is only 600 km wide and 400,000 km long and
      600 km transverses Mars. The error ellipse of course still crosses Mars, but given this error ellipse, it could still pass many 100,000's of km away.

      I have to say, though, that having the 600 km wide part of the error ellipse cross over Mars makes me suspect that this object is going to come pretty close to Mars.

      Either Phobos or Deimos could also be hit with this error ell
    • I wonder which will be the first of the three Mars-orbiting spacecraft currently active to observe it ?

      It would also be interesting to know if, given that there's an impact, the Opportunity Rover has a chance of seeing it. One report describes the possible impact point as "north of" the rover, but doesn't say how far.


  • Does Hot Fudge Sundae falls on a Tuesdae that week?
  • Impact results (Score:4, Informative)

    by lpangelrob ( 714473 ) on Monday December 31, 2007 @12:40PM (#21866760)
    No one's brought up the consequences of a collision yet, so here it is, from the first press release []:

    If the asteroid is indeed on a collision course, it would hit Mars with a velocity of about 13.5 km/s (8.4 miles per second), and would produce an explosion equivalent to about 3 MT of TNT. We can only speculate as to the effects of such an impact, but it would be reasonable to expect a crater nearly a kilometer across and a significant amount of dust lifted into the atmosphere.
    It also notes the asteroid is 160 ft / 50 m across, and any impact probably will not be observed (by human eyes, anyways) because it will impact Mars where there are no instruments.
    • by teslar ( 706653 )

      any impact probably will not be observed (by human eyes, anyways) because it will impact Mars where there are no instruments.

      It says no such thing in the press release you linked to. Regarding instruments, all it says is:

      The zone of potential impact on the surface of Mars is approximately 800 km wide, and sweeps across the Martian equator from southwest to northeast, crossing the equator at roughly 30 deg W longitude. The MER Opportunity rover is close to the southern edge of this possible impact zone but c

  • by Ed Almos ( 584864 ) on Monday December 31, 2007 @12:47PM (#21866844)
    2007 TU24 - approaching
    Approximate diameter: 319 meters (H=20.131)
    Closest Earth approach: 1.44 LD at 0826 UTC on 29 Jan. -----
    Inside ten LD of Earth: 24 Jan. until 3 Feb.
    Inside Earth's Hill sphere: 27 to 31 Jan.
    Closest Moon approach: 2.20 LD at 1533 UTC 29 Jan.
    Data based on: JPL SSD orbit solution #13 downloaded 6 Dec.
    based on 87 observations spanning 54 days
    Optical observation: observed from 13 locations during 53.8661 days
    discovered at 0626 UTC on 11 Oct. by the Catalina Sky Survey
    last observed at 0313 UTC on 4 Dec. by the Spacewatch 1.8m telescope

    This shows that a rock 319m in diameter will pass by the Earth on January 29th 2008, it's closest point will be about 1.4 times the moons orbit or about 357,000 miles. This is VERY VERY close.


    Ed Almos
  • Good thing (Score:3, Insightful)

    by bytesex ( 112972 ) on Monday December 31, 2007 @01:00PM (#21866998) Homepage
    Well then, it's a good thing we're not living there yet, isn't it ?
  • Get your asteroid to Mars!
  • So....

    How hard would it be to launch a nuke and hit the asteroid in such a way that increases it's chances of hitting mars?

    Of course this would probably cause an interstellar war with the Martians, but still...
    • Re: (Score:2, Funny)

      by railman99 ( 1060664 )
      "Of course this would probably cause an interstellar war with the Martians, but still..."

      Nah, that war with the Martians ended 65 million years ago, when they blew up the home (5th) planet with their worm hole doomsday device, and both camps of survivors in space settled the only viable candidate planet in this Solar System, Earth. Yes, we are their descendants. LETS TRY REAL HARD NOT TO REPEAT THE SAME MISTAKE TWICE IN A ROW, PEOPLE!
  • The rovers (Score:4, Interesting)

    by ACS Solver ( 1068112 ) on Monday December 31, 2007 @01:21PM (#21867252)
    Is there any information yet on whether Spirit and Opportunity might see anything if there actually is impact - such as maybe seeing the dust rise or even capturing a glimpse of the asteroid in the Martian atmosphere?
    • Re: (Score:2, Funny)

      A calculation using Murphy's law suggests direct impact on Spirit with a sub-orbital bounce to Opportunity.
  • The reason I note that is because if it hits, the predicted time is 2:56 am PST Jan 30.

    Note the PST please. Now, that translates to 5:56 am EST, and its going to be well on its way to brightening up for the day here in WV. I had visions of setting up my elderly DS-10 with my Sony TRV-460 hanging on an eyepiece adapter with a 37mm thread and a 25mm eyepiece in the adapter so I could record the event if I can collect enough light to actually do a movie at ntsc frame speeds. That will also put it (I'm makin
    • by pease1 ( 134187 )
      If you are serious, get on a plane and take your stuff to Hawaii. From WV, even if it is above the horizon, you'll be looking through so much of Earth's atmosphere you won't see any detail on the surface of Mars anyway. From Hawaii, however, the red planet will be nice and high in the sky. Assuming something happens and the 96% chance that it won't occur are beaten, and it's clear, the package of scopes on Mauna Kea will be very nicely placed.
      • That assumes I have a card that I can deplete by a mid 4 digit amount just for transport. Retired, with SS as the main income, that is not the case.


        Cheers, Gene
        "There are four boxes to be used in defense of liberty:
          soap, ballot, jury, and ammo. Please use in that order."
        -Ed Howdershelt (Author)
        A lifetime isn't nearly long enough to figure out what it's all about.
  • by martyb ( 196687 ) on Monday December 31, 2007 @02:11PM (#21867916)

    "The probability of asteroid 2007 WD5 impacting Mars has been revised [CC] following further observations. The chance of impact has increased from 1.3% to 3.9%"

    But what about 2007 WD40 []? My bet is that one WILL slip past us! <grin>

  • by Chris Tucker ( 302549 ) on Monday December 31, 2007 @02:12PM (#21867922) Homepage
    is the tons of utter bullshit that Richard Hoagland will then spew about all the fantastic discoveries revealed by the impact, proving that there was an advanced civilization on Mars, that NASA is suppressing.

    Dear Jeebus, please let the asteroid hit the "Face On Mars" dead center, just to piss off that con artist Hoagland.

  • by xENoLocO ( 773565 ) on Monday December 31, 2007 @02:27PM (#21868120) Homepage
    The asteroid will bust through the surface crust, exposting Mars' nougatty, caramel-filled center.

  • by WalletBoy ( 555942 ) on Monday December 31, 2007 @03:23PM (#21868788)
    "Never tell me the odds!"
  • "Mars Asteroid Impact More Likely Than Before" doesn't look right. Seems to me the probability hasn't changed at all, in fact the only thing that changed was the precision with which the probability was calculated. Or am I missing something, and should just resume my New Years Eve drinking binge?

If you think nobody cares if you're alive, try missing a couple of car payments. -- Earl Wilson