Monday, September 03, 2007

Disaster Simulation

My move into the new apartment went fairly smooth, with only minor disasters (like my landlord drinking coffee at Tim Horton's while I needed her key to service the elevator). Currently I am sitting in between half unpacked boxes and unassembled furniture (more fun to come). The whole place looks like after a medium asteroid impact.

In case you are tired about end-of-the-world scenarios that feature global warming predictions, here is something for a change: 99942 Apophis is an near-earth asteroid with a diameter of roughly 300 meters. It orbits the sun but crosses the path of earth. According to present day observation, it is estimated to hit the earth in 2036 with a probability of about 1-in-45,000 [source] .

The asteroid, initially named 2004 MN4, was discovered on 19 June 2004 by Roy Tucker, David Tholen and Fabrizio Bernardi of the University of Hawaii Asteroid Survey (UHAS), from Kitt Peak, AZ. In December 2004, preliminary observations showed it might strike in 2029 when the asteroid will come closer to earth than some of our satellites. But further investigation ruled out the 2029 impact scenario. The possible impact in 2036 however can not yet be ruled out.

[Picture: NASA]

Astronomers rate dangerousness of asteroids and comets on the Torino Impact Hazard scale. The higher the value, the more dangerous the object. Apophis reached 2 out of 10 [source] that is "A discovery, which may become routine with expanded searches, of an object making a somewhat close but not highly unusual pass near the Earth." Moving scores 5 out of 10 "A close encounter posing a serious, but still uncertain threat of regional devastation."

To accurately predict the risk, the Planetary Society offers $50,000 in the Apophis Mission Design Competition to design a mission to rendezvous with and "tag" the asteroid, i.e. leave a device on the asteroid that allows tracking it very precisely. The deadline for the competition was on Friday, Aug. 31st 2007. According to their website, more than 100 teams and individuals from 25 nations intend to contribute to the mission.

But here comes the fun: You can estimate the consequences of an impact online on this interactive Catastrophe Calculator (calculate your own crater!), provided by the Dept. of Planetary sciences at the University of Arizona. For the visually and rethorically upgraded version, see NOVA: The asteroid that hit LA. (So much about 'catchy' titles.)

To the younger readers out there: here is your chance to save the planet! Needless to say, intimate knowledge of physics is necessary for this noble task.

Further reading:


  1. Yumm, ordinary chondrites. :-)

    And I think Apophis is Torino scale 0 or 1? (depending which date you are referring)

  2. Hi Amara: Yes, I think it was lowered to 1 after the 2004 flyby, and to 0 sometime last year. Sorry, it should have been 'reached' not 'reach' in the post, I've corrected that. Take care - B.

  3. Hi Bee,

    congratulations for surviving the move - in the US it is not such a big deal as in Venice, but still maddening (one day I will describe the Torino-5 event of my 2005 move in Venice, which involved constructing an elevator on the outside wall of the house up to the 5th floor, passing all the furniture pieces through a window and down, then bringing everything into a boat, and then driving it to the other place, disembarking, constructing another outside lift to the third floor, lifting one box at a time up and through another window, etcetera, etcetera...

    A comment on your sentence "it is estimated to hit the earth in 2036 with a probability of about 1-in-45,000"... I think if you wanted to be deliberately a catastrophist you managed well. I would have rather said "it is estimated to miss the earth in 2036 with a probability of about 45,000 to 1".


  4. Hi Tommaso:

    Well, yes. I've kind of tried to be a catastrophist and get close to a headline like 'The asteroid that hit LA', but I guess I have slipped back towards sarcasm prematurely. But hey, we're all going to die anyhow.

    Wow, your move sounds as if it would score considerably higher on the impact scale than mine. I just had this one awful second yesterday when we were standing with the couch in front of the apartment door, and I thought what if it doesn't fit through? My most annoying move though was neither in the USA nor in Europe but the one crossing the big water. Not recommendable. Best,



    Strongly worded petitions and faith will save us. Everybody must run 100 miles to save the Earth. Concert to Save the Earth.

    The real solution is to overstaff ISS FUBAR with Inner City grade school diversity teachers - but there is hardly time enough to do studies.

  6. I wonder if we could tweak its' orbit juuust right so it can be captured and put into orbit around the Earth.

    Have fun with stationkeeping though...

  7. My most annoying move though was neither in the USA nor in Europe but the one crossing the big water. Not recommendable.

    Agreed. :-(

    (Second cross-Atlantic and third international move in 9 years coming up)

  8. Hi Bee,

    "An additional impact date in 2037 has been identified; however, the impact probability for that encounter is 1 in 12.3 million."

    I wonder if the 2036 perturbation will effect the 2037 probability?

  9. Hi Bee,

    I hust encountered this BBCnews story: 'Clearest' images taken of space.

    "The images are twice as sharp as those from Hubble Space Telescope.

    The new system, dubbed "Lucky", is the result of work by a team from Cambridge University and the California Institute of Technology (Caltech)."

  10. Bee, only your apartment looks like a moderate asteroid impact. After a move, I'm as though the asteroid hit me.

  11. In case anyone here is following Dawn and they want to learn more about the Asteroid belt, I updated the launch date here (which is now September 26). Note that if the project misses this last window, which ends middle October, that's it for about 17 years. You can track the more-or-less current news for Dawn at Wikipedia as well.

  12. The way I feel today, an asteroid impact might be an improvement. ;-) I hope your unpacking goes smoothly!

  13. I enjoyed how you thoroughly "debunked" David Gross' statement. Are you really so dumb, Sabine, or do you just pretend it?

  14. I did what? And yes, of course I am really too dumb to pretend anything, thanks for asking. - B.

  15. Ah, I see. Must have missed the sentence that said it was a quotation from David Gross. I couldn't avoid having the impression it was a little too simplistic, and the term "perfectly acceptable in almost every other field of science" seems to imply a restriction on 'other fields of science'. I want to see somebody who'd be satisfied with the 'qualitative prediction' that a space-shuttle can fly to the moon, there are really a lot of real numbers some of which are transcendental, or Plutonium is kinda unhealthy. In case it ever becomes 'perfectly acceptable' in medicine to make the qualitative prediction: you're going to die, it might be just around the corner, but maybe very very far away - I think I'd rather invest my money elsewhere.

    It is probably a waste of time pointing out that I understand in some areas of science - like e.g. this part of theoretical physics - qualitative statements are a pre-stage for quantitative predictions, in many cases either necessary or at least helpful to move on. I was just disturbed by the generality of the quotation (that however, might have been cited somewhat out of context, I don't know). Hope that clarifies it.



  16. Some have simulated Apophis destruction, as well.

    (Bee, for a thought experiment, substitute your least favorite blogger in Apophis' place)

  17. Bee (and Stefan), you write one of the best and most informative physics blogs around. Unfortunately some amount of bad vibes goes with that territory, seems to be inevitable. Nevertheless try to keep in mind the real life consequences of all that occasional heckling (not much), and keep on with the good work.

  18. Hi Bee,
    I never cease to be amazed by your patience and optimism in trying to engage Lubos in serious discussions...given that it always ends in the same predictable way. How about sparing yourself the aggravation and just using him as a source of entertainment instead? The fun thing about fanatics is that they are usually easy to wind I recommend to you the sport of "motlbaiting": The goal is to wind Lubos up so badly that he has to write a whole new blog post full of abuse to recover :-) It's good fun, you should try it! ;-)

    Best wishes,

  19. Pace amused, I suggest "ignoring is bliss".

  20. (Bee, for a thought experiment, substitute your least favorite blogger in Apophis' place)

    lol Amara, that IS some thought experiment, we can Bee thankful the human mind is not so evolved that it can pulverise asteroids by sheer thought or will power, it is dangerous enough thing as it is.

  21. well, since the human body is essentially a bag of water, I guess the result would be a rather disappointing blot on the earth's surface that would be washed out by the atmospheric conditions within a couple of days. Luckily, I have a couple of infinities around to renormalize my scale of importance on which a stone flying through outer space still ranks higher than certain bloggers. thanks for your support, B.

  22. Bee: I find it hard to comprehend that you are married to Stefan and not to Lubos given the degree of bickering and making up that goes on

  23. OUCH gordon!... I would never wish Lumo on anybody... not even woit!... ;)

    Bee, you must know that I have to ask what effect on the odds there might be if, as is directly observed, there is an biocentric cosmological principle in effect?

    Does the motion of the solar system affect the microwave sky?

    LambdaCDM cosmology: how much suppression of credible evidence, and does the model really lead its competitors, using all evidence?

    Alignment and signed-intensity anomalies in WMAP data

    Extragalactic Radio Sources and the WMAP Cold Spot

    A second paper confirms that the CBR is not symmetrical, as conventional theory predicts, but is asymmetrical on both large and small scales.

    Testing Isotropy of Cosmic Microwave Background Radiation

    A third paper on this subject raises doubts that the radio radiation from our own galaxy can be so accurately subtracted from the CBR observed by WMAP that the precision claimed for CBR measurements are valid.

    Some doubts on the validity of the foreground Galactic contribution subtraction from microwave anisotropies

    Michael J. Longo, who had previously shown that there was an alignment in the direction of spin of thousands of spiral galaxies across a huge stretch of the universe, shows the same alignment for elliptical galaxies.

    The Axis of Opportunity: The Large-Scale Correlation of Elliptical Galaxies

    But when you look at CMB map, you also see that the structure that is observed, is in fact, in a weird way, correlated with the plane of the earth around the sun. Is this Copernicus coming back to haunt us? That's crazy. We're looking out at the whole universe. There's no way there should be a correlation of structure with our motion of the earth around the sun — the plane of the earth around the sun — the ecliptic. That would say we are truly the center of the universe.
    -Lawrence Krauss

    Willful denial is mightier than reality...

  24. island, would you please stop advertising your favorite topics on posts that have absolutely nothing to do with it, thanks - B.

  25. btw, I have tried to tell you an almost infinite amount of times that your 'principle' is ill defined, unless you can give me a definition for 'life' and explain the factor about it that is 'optimized'. as it is, your 'principle' is a very good example for a completely empty word idea that is not even wrong. best,


  26. Well, you're pretty much right about my being off topic, so I won't try to do that here, as I came here through a link and didn't properly read what the thread was entirely about, sorry.

    Not that I can't answer your question, but I don't believe that it would really make a difference anyway.

    I'll remove my post if you'd like, or you can, and I'm sorry, I was just being overly enthusiastic, and I'm sorry, I was trying not to do what I just did... duh.

  27. just try not to repeat it. I'm still chewing on the arrrow of time, but sooner or later I'll have another post on these issues. all the best - B.

  28. Hey, I do think that there is an effect on the probabilities for a devastating astroid strike that have to be taken into account "to accurately predict the risk", or you're just in denial of what is directly observed... and that has nothing to do with my pet theory, much, except that direct observation typically agrees with me, is all, and that would make sense if I was on the right track.

    Just sayin... ;)

    I'll runaway fast now... byE!

  29. well, how about you send a proposal to the Planetary Society telling them the probability for an asteroid impact is zero because the universe is biofriendly, and wouldn't hurt such nice people as us?

  30. I didn't say that because I think that the structure of the universe is self-regulating, and "bio"-centric applies to every galaxy structure within the observed habitable zone.

  31. well, how about you send a proposal to the Planetary Society telling them the probability for an asteroid impact is zero because the universe is biofriendly, and wouldn't hurt such nice people as us?

    Haha, us knowing what we are, we should be paranoid that the universe is out to get us.

    But there is a serious scientific reason why the probability for human extinction from an asteroid impact (or any other cause) is zero, namely the anthropic principle won't work any more.

  32. ;-) well, I was trying to avoid the A-word.


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