10 responses

  1. Sergey Kurdakov
    April 3, 2013

    there is no active government program to identify threats

    this is pretty much false statement, which is unfortunate to read on a blog with good reputation. There is a video https://www.youtube.com/watch?v=xJsUDcSc6hE and page http://neo.jpl.nasa.gov/stats/ ( and http://en.wikipedia.org/wiki/Large_Synoptic_Survey_Telescope and https://en.wikipedia.org/wiki/Pan-STARRS ) – after looking at these links it is not possible to say, that there is no program – there are programs, they are not just enough to track all potential problems quickly. The next problem is that last really big cosmic problem was in 1908 and the probability to repeat the same is one in 1000 years. So what to deflect if nothing is known? The sane approach would be – to detect the problem that possibly could harm earth in say near 100 years, then make something. And with Pan STARRS and LSST – in 20 years we will know all problems.

    So given that we know almost all 1 km and 300 m wide asteroids what is probability that we are severely harmed in next 20 years? Quite low. The simulations show that Pan STARRS (which already works for several years ) would detect most of serious threats 2 years before collision ( it is actually more complex to track those asteroids which are about to hit us in 2 years ), so even if we are about to be hit in next 20 years – we will have some time to make preparations ( count on the fact – that when the problem is real – the creativity of people is really high ).

  2. Jasper Johns
    April 3, 2013

    An earth dooming asteroid? Check. Just read about it all in the funny new novel THE MYOSHI EFFECT.

    • cwade
      April 3, 2013

      Great story. I read something similar a few weeks ago that mentioned work being performed by companies such as SpaceX, Planetary Resources, and Stratolaunch Systems to realize the commercial potential of such ventures. Good stuff!

  3. Alain Maury
    April 3, 2013

    I guess enthusiasm is no excuse not to be precise.
    “There has been much talk in the media about what to do since last week’s astronomically unlikely double asteroid attack” -> As far as I know there was no attack. An attack is a deliberate action. Here it’s just a consequence of us being there while an asteroid passed by (2012DA14 did not hit us, far from it), and the Chelyabinsk event was really not caused by an asteroid, but by a meteoroid. Nobody was killed, and it’s part of these events occurring every century, but very rarely over a city.

  4. Alain Maury
    April 3, 2013

    Continuing :
    “Many people are asking, “What is the government doing about this?” Well, the answer, sadly, is not much”
    This is completely false. In the Apollo era, there were 23 near earth objects known, and we are now approaching 10000, and the vast majority of them were discovered by NASA financed search programs. You could say this about ESA, but not about NASA. None of the asteroids discovered present any danger of hitting the earth anytimes soon, and it is very likely the case for all the ones remaining to be discovered, down to 100 meters of diameters (small asteroids like this hit the earth on average every 1000 years or so, so there is a 10% probability that one of these small guys will hit us in the coming 100 years… But for slightly larger asteroids, the probability of an impact is infinitesimal, you should know that. So let’s discover them, and not worry about them anymore. If you want to spend money saving human lives, there are really a lot of other projects related to education, medicine, fight against religious bigotry and the like… They kill many more humans than asteroids, who really don’t “attack” us.
    While I think that the B612 foundation Sentinel project is a very good project, worth doing, I don’t believe putting a telescope on the moon is economically wise. You can put a much larger telescope on the earth, or hundreds of them on the earth, for the same price of a telescope which will be very hard to maintain on the moon. Nice idea, just that I don’t believe it.

    • Michael Busch
      April 4, 2013

      I see that I was in significant part echoing Alain. We were typing our comments at nearly the same time.

      Good to see that we are in agreement.

  5. Michael Busch
    April 3, 2013

    No, the Moon is not a natural platform for asteroid mining, detection, or deflection.

    Current asteroid retrieval and mining schemes are all based around using low-thrust high-specific-impulse propulsion, such as ion engines. This makes it possible to bring large masses of material to Earth-Moon space. But such engines _can’t_ be used to land on or leave the Moon: the gravity is too high. Lunar _orbit_ is interesting as a place to park returned asteroid material. The lunar surface itself is not.

    Earth-based asteroid surveys have been very successful, and are becoming even more so. Space-based projects like Sentinel can go to better locations to find more objects more quickly. Putting an optical or infrared survey telescope on the surface of the Moon would be little better and far more expensive than putting one on the surface of the Earth.

    Re. deflection: the goal is to find all objects large enough to be worth deflecting decades before they hit, so that relatively small deflection missions can be launched from the Earth. Impactors too small to be worth detecting will be found with days to weeks of warning, more than sufficient time to evacuate the blast zone. The Moon has no role in this.

    The Moon’s presence does not significantly change the number of impacts onto the Earth, because an object on an Earth-impacting trajectory is very unlikely to pass near the Moon on its final approach and the Moon is not large or fast-moving enough to significantly scatter objects off of Earth-crossing orbits (and a significant fraction of small objects in the near-Earth population are pieces of lunar ejecta). Nor was the conjunction of the Chelyabinsk event and the flyby of 2012 DA14 “astronomically unlikely”. An object the size of DA14 or larger flies within 1 lunar distance of Earth on roughly a weekly basis. Therefore, given that the Chelyabinsk event happened, there was roughly a 50% chance of an object like DA14 passing close to the Earth within 48 hours of the impact. DA14’s flyby was unusual in that we knew about it a year in advance.

    There are many reasons why exploring the Moon is scientifically interesting, and there may be some possibilities for space resource utilization – particularly at the lunar poles (although many near-Earth asteroids require less fuel to get to). Do not dilute those with inaccurate claims.

  6. aa
    April 3, 2013

    “The Moon acts like an asteroid magnet” – Wow, what a terrible article. The author should probably read up on like, gravity, and how little the moon’s affect things traveling at many km/s. Good luck harvesting basalt…

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