A science blog with Eric Berger




But Mars? That might be interesting.

And NASA scientists say a large comet could collide with Mars in October 2014. The chance is not high, it’s about 1 in 2000, scientists estimate.

Still, because the comet is so large even a small chance of a collision is a big deal. Astronomers estimate the comet, 2013 A1, is 1 to 2 miles across and capable of delivering an impact of 35 million megatons of TNT, or about the third of the energy of the asteroid strike 65 million years ago that wiped out the dinosaurs.

Were such a rock to strike the Earth it would threaten civilization as we know it, whether it hit land or ocean.

But such a comet striking Mars would represent a most excellent scientific experiment.

Even a near miss would look spectacular. (NASA)

Such an impact would blast dust, sand, water and lots of other stuff into the atmosphere of Mars, likely making the planet wetter than it is today. Scientists say the Opportunity rover, powered by the Sun, would probably die as a result of an impact. Curiosity, unless directly affected by the blast, would survive because it is powered by nuclear energy.

There will be plenty of eyes in orbit around Mars to watch a potential collision, with the Mars Reconnaissance Orbiter, Mars Express, and 2001 Mars Odyssey all likely to provide views of such an event. Even a near miss could be pretty spectacular.

We should know one way or the other about an impact within a few months.

Categories: Astronomy, National, Space
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Eric Berger

51 Responses

  1. jasonB says:

    Can we petition NASA to nudge this thing to assure a hit? They can call it practice on helping to save Earth if one’s on a collision course with us.

    • JohnD says:

      Unfortunately, there isn’t enough time to launch a mission to nudge the comet (assuming that we had something that would do the trick {which we don’t}).

    • jasonB says:

      Darn. Kind of a tongue in cheek comment and kinda figured it wasn’t possible (was hoping), but boy oh boy, what a show!

    • George says:

      Problem is with NASA’s luck it would nudge it into an orbit crossing ours.
      This would NOT be a good thing.

  2. Space Nerd says:


  3. Conrad Young says:

    Could we purposely crash it into Mars as a scientific experiment? We could test out gravitational tractors and possibly begin terra forming Mars if we crashed it into the polar ice caps.
    If it did crash, how long would it take for the atmosphere to settle?

  4. TxAg says:

    As long as it doesn’t knock down our flag.

    • Eric Berger says:

      I believe the SJL-flag meme is the second-most popular one on this blog after the Katy joke.

      Not that I mind!

    • J. Reynolds says:

      Gig ‘em. The Katy joke is just so atrociously stupid that it never gets old. It’s not unlike that ancient Three Stooges bit where Curly says, “I’ve got a weak back.” Moe: How long have you had it? Curly: About a week back.

    • Sheila Jackson Lee says:

      I completly agree…this is not a good idea to endanger the American flag that Atronaut Armstrong planted on Mars in 1967. As the chairwoman of the space science committee, I strongly urge that a new tax be placed in order to keep this event from happening, and we must be sure to protect Mars with all due course.

  5. Choice says:

    I think a comet “dirty snowball” is what the biblical Wormwood is about. A comet is more dangerous than a meteor because of speed and it isn’t just rock. It is ice and gas. The gas would be toxic to our drinking water, food,and entire environment. I’m sure that is what wiped out the dinosaurs and could be the reason Noah needed an Ark. This will be an interesting event. I can’t wait.

    • Jscott1 says:

      You are talking biblical mythology in a science blog…seriously?

    • Deez says:

      The “reason” Noah needed an ark. OMG, are you drunk?!!?

    • Glenn Beak says:

      Unless the Ark orbited the Earth for 40 days and 40 nights it wouldn’t be much protection from a comet strike. If you want to believe in miracles don’t try to shoehorn them into science.

  6. flypusher says:

    Very nice of Mars to take the hit for us!

  7. Bruce says:

    I didn’t know that the vehicles planted any flag on Mars like our astronauts physically did on the moon ages ago and I saw them do it via television. If a flag should be planted on Mars it should be the Texas one because it is the only part of this country where freedom may still reign, and that’s no yoke.

  8. saved says:

    I can assure you that no asteroid strike 65 million years ago wiped out the dinosaurs. Also with a 16 plus trillion debt and borrowing over 46% of every dollar spent we need to shut down all unnecessary spending and NASA space spending is unnecessary.

    • fencesitter says:

      not from a sicence point you cant.

    • penny says:

      Obvious troll is obvious. Try harder.

    • Peterr says:

      saved, what a boring life you have.

    • Woohoo says:

      Oh so were you there? and what? you saw nothing?.. oh wait.. impossible because in your view the Earth is only 6000 years old…

    • fox459 says:

      WOW, thank you for making all Christians look ridiculously stupid. NASAs budget is 1% of 1 penny of every dollar of the federal budget. NASA is the only agency that really contributes to the betterment of mankind.

      YOU and people like you are why I do not go to a church anymore, I just can’t believe how stupid you are.

      We need to cut all the freaking welfare and a big chunk of the defense dept budget and give it to NASA so we get more than a two week notice for killer asteroids.

    • sack_o_cats says:

      NO spaceflight article is complete without ‘saved’ contributing his usual Anti-Science diatribe… which he usually disguises as a budget-saving measure. His comments in other forums betray his true nature, however… he is a creationist, and a literalist re: his chosen holy book (with all that implies).
      He can usually be found hanging around in the comments section of crime articles, advocating the use of Singaporean-style Caning as a punishment for the miscreants.
      With all that implies…

    • Joe says:

      It’s funny how “saved” can you you people all worked up like this. Just read on and try not to act like idiots in response. Take it to another level. As dumb as his views seem to you, don’t bring yourself to his level by insulting millions of Christians who do accept science along with faith and history.

  9. Scald says:

    Great to know that Katy is not in eminent danger. Next, the aging NASA Astronaut Corps that makes decisions for future trillions of space bucks needs to quietly exit stage left. Enter a group of nerds, mathematicians and scientists who can make educated guesses, based on science and the latest advances, about the little rocks and comets out there that could turn the earth into a science project. Go, nerds.

  10. Jack says:

    By the way, there is part of the scientific world that does not buy the theory that an asteroid impact killed the dinosaur population.

  11. Randall Kallinen says:

    If they do not know if it will hit Mars then they do not know whether Mars can alter the comet’s trajectory by gravity so that it would hit Earth. Small chance but a chance.

  12. Edward says:

    Having a comet hit mars = awesome. Having a big chunk break off as a result and aim at Earth = totally awesome!

  13. JimH says:

    I wonder what the loss of mass would do to Mars and how it would affect Earth’s orbit around the Sun?

  14. MrOldMan says:

    I’d feel a lot better about our chances if we started practicing on some of these. We need to be ready.

  15. MrOldMan says:

    You religious folks need to realize that science is about facts. Not myths or superstition. We know that our planet has been hit by huge objects millions of years in the past. It is not open for debate.

    • SomanydynamoS says:

      Religious folks know science is based on as many theories and hypothesi as it is facts.

    • sack_o_cats says:

      And that is where they (and many others) are mistaken.
      The Scientific Method isn’t about ‘proving what something is’… it is about ‘proving what something cannot be‘, in order to arrive at the truth of a matter…
      Or, as is usual, find that new discoveries lead to new questions that no one ever knew to ask! Knowledge builds upon itself

      Re: ‘Facts’, ‘Theories’, ‘Hypotheses’, etc…
      Those terms aren’t used the same way amongst scientists as they are amongst non-scientists… they can pretty much be regarded as ‘Jargon’, but this doesn’t keep the Anti-Science crowd from attempting to try and score points amongst their brethren by using those terms out of context.

  16. RichardRoma says:

    (bleep) this. I’m out of here.


  17. drumb47 says:

    Our Universe doing what it does.

  18. Mike says:

    If the comet misses, it’s orbit will be deviated by Mar’s gravity well, could it then become a threat to Earth?

  19. Paul Robison says:

    Dr. Berger:

    Wouldn’t you say our neighbors in Austin face a similar dilemma as Mars? I’m talking about a (possible) collision course with a North Korean nuke. What effect would that have on Houston, which is three hundred miles away?

    • tanstaafl says:

      How slow are you driving? It’s only 160 miles or so from Houston to Austin. Also, if I were Kim Jong-un, I’d lob a nuke at Houston instead of Austin, given the amount of refining and the number of pipelines that run through our area.

    • sack_o_cats says:

      And either way, Katy is doomed

    • marcopolo32 says:

      Lil Kim is targeting Austin because there is a big Samsung facility there.

  20. PostalKen says:

    Where’s Dr. Who when you need him?

  21. Gezzr says:

    With all the currently accepted theories that comets brought water and “life” to the Earth may the “scientists” should look at a ‘proof’ of their theory with a comet delivering the same to Mars. With nearly a year to prepare they need to get their act in order and get their measurements and samples as a benchmark for before and after comet impact.

  22. craig says:

    35 million tons of TNT? Sure good to get this out of the way before we humans set up shop on Mars as the get a way place to avoid a life(especially ours) extinction event here at home.

  23. Mike says:

    Say that same comet were to hit the Earth, wouldn’t the blast be bigger because Earth has more gravity causing the impact to have a greater delta V?

  24. Someone says:

    What’s the minimum time transit to Mars orbit for a probe?

    If we know it’s going to impact, it would probably be worthwhile to delay other projects and get something over there specifically for the observations.

    Minimum transit time + minimum build time + small margin for delays = Latest date at which to make a decision.

    • JohnD says:

      The minimum transit time depends on a number of factors including the relative positions of Earth and mars (e.g., we cannot use a minimum-energy Hohman right now because the planets are in the wrong positions), the amount of thrust the probe has (e.g., high energy chemical rocket or low energy ion drive), when and how long it uses that thrust (e.g., boost and coast or constant drive), etc.

      Right now, it would probably take on the order of a year and a half to get anything to Mars. So we’ve missed the boat for this event.