Odds of Mars Strike Now 1-in-25

A week ago I told you about a small asteroid with roughly a 1% (1-in-75) chance of hitting Mars late next month.

Asteroid to hit Mars?
Estimated to be about 150 feet across, the small asteroid designated 2007 WD 5 will pass very close to Mars — and might hit it — when the two cross paths (upper left) on January 30th.
Well, the odds of an impact have just gone up!

Earlier today dynamicists at the Jet Propulsion Laboratory announced that 2007 WD5 now has a 1-in-25 chance (4%) of striking the Red Planet. They've adjusted the prediction based on the asteroid's serendipitous appearance in three images made November 8th, nearly two weeks before its discovery by the Catalina Sky Survey team on Mount Lemmon in Arizona.

Most likely, 2007 WD5 will miss Mars by about 15,000 miles. But if it should strike, it will do so at about 8½ miles per second on January 30th, within a few minutes of 5:56 a.m. Eastern Standard Time.

No observations of the little asteroid have been acquired since December 19th, though new images — and a much better prediction — should be made within the next few days.

18 thoughts on “Odds of Mars Strike Now 1-in-25

  1. Tochtli

    In an hipotetic case that the asteroid hit martian grounds could be watch by a normal scope or this impact just could be notified to us (amateur astronomers), i dont know by some profesional institution?
    I addressed this in the first story last week. If the asteroid were to hit, it would create a crater roughly a mile across. This is too small an impact to be observable from Earth, but it would be easy for any of the three spacecraft now orbiting Mars — Kelly Beatty

  2. charles botkin

    If the asteroid hits then many amateur scopes should be able to see the debris cloud that is thrown up.
    That is as long as a large dust storm is not obscuring the event.

  3. Dennis

    Aside from missing Mars, what are the chances of 2007WD5 hitting one of Mar’s moons. Obviously much smaller targets, but since the asteriod is now closer to missing at 15k, this is in the range of its moons locations. Or is 2007WD5 on a high incline in relation to Mars two moons?

  4. MIke

    Looking at this from a scientific perspective, this would produce a windfall of information. There is much attention on Mars now that we are planning a manned mission. Since there already have three satellites in orbit around the planet,and rovers, a tremendous amount of data would be collected. We already spent billions blasting a comet with an impactor. This could save us a lot of money. I almost feel guilty hoping for an impact, but this would give us much insight into what would happen on earth should such an event occur. It could answer the big question, is there water on Mars? Spectroscopic analysis of the dust cloud would likely reveal composition far deeper than we be able to determine for many years. A tremendous amount of information was collected when Shoemaker-Levy stuck Jupiter. Jupiter is a gas giant. Mars is a solid planet, much like earth. The chances have increase from 1 in 75 to 1 in 25, a four fold increase. I looked at the JPL sight and it said if an impact occured. The latest information is indicating the impact would occur about 12:56AM CST, with no lunar interference.

  5. MIke

    I know the article said we couldn’t see the crater with a amateur telescope, but could we see the flash? Flashes caused by much smaller meteors hitting the lunar surface have been observed.

  6. Mike

    Its 2:56AM PST, so that would be 4:46AM CST, Not 12:46AM as I wrote above. Mars will have set by then in the Central Zone, but they may be able to see it in the Pacific Zone.

  7. Mike

    Its 2:56AM PST, so that will be 4:46AM CST, not 12:56 as I wrote above. It will have already set in the Central Time Zone. It may still be visible in the Pacific Zone, though. As far as the Interactive Sky Chart, I think its broke. I have been getting an error message since Monday.Something about the database is full.

  8. RoD

    I know it’s unlikely, but could the operation of the rovers Spitit and Opportunity be effected by an impact? Or could they provide any usefull information should the impact occur near them?


  9. Ken

    If the asteroid does strike Mars, we might assume it could be full-frontal – making it sooner rather than later. If it is a glancing strike at the “edge” of the aparent circle, the meteor must travel much further to travel from the “closest (to Mars) facing surface – to a farther point; e.g. if an asteroid came into earth at the north pole directly from that direction with little to no arc, it would take hours more for it to crash at the equator – because that’s ~13,000 farther from the north pole.

    Then too, it could be snagged by Mars’ gravitational force and do a “backdoor” or multi-orbit corkscrew. All of which would make actual strike-time very soft.

    Given the size of the asteroid and Mars’ moons, a meeting of the two seems about as likely as me winnng the lottery.

    I suspect we’ll know a lot more by mid-January

  10. Mike

    I think the real question here is what happens if it misses? It seems to me, that there is a real possibility of this going behind Mars. It looks to me like that could be a perfect setup, to slingshot the asteroid right back at Earth!

  11. Marc

    A site in my mothertongue (Dutch) said the following when 2007WD5 was discovered: “Mars will be impacted by an asteroid! The chance of impact is 1 in 75. Scientists expect the chance of impact to rise in the coming week”.

    When I posted that wasn’t possible, the next post said: “if you don’t believe it, don’t post here, you moron. just go to another site!”
    In other words: critique wasn’t expected nor accepted.

    But it keeps on bugging me. Is it possible to EXPECT THE CHANCE OF SOMETHING TO HAPPEN WILL RISE?


  12. Alf

    The detection of near planet crossing trajectories is increasing and likely to continue to mount as the entire solar system moves into more densely populated regions of the near by galaxy {The Milky Way}. This has been better and more thoroughly detailed elsewhere. The need for widespread and regular observations cannot be overstated at this juncture, from both objects entering the solar system and from perturbations of the orbits of smaller sized bodies within the solar system {Kuiper and Asteroid, etc belts]. The likelihood of local impacts shoud not be discounted. Neither should recomendations to pursue other than conventional safeguards be ignored.

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