Another Close Approach

An asteroid will pass us on Sunday at about a tenth of the distance to the moon.

There are a lot of natural disasters we won’t be able to prevent (e.g., supervolcano explosions, or a nearby gamma-ray burst). But this is something that we could, if we were willing to devote more resources to it. And it wouldn’t take a lot more. In fact, it could be done for a lot less than we’re wasting on SLS/Orion.

16 thoughts on “Another Close Approach”

  1. Missing us by the diameter of the earth, more or less?

    Sure, nothing to worry about! Return to squirrel watching, citizens!

    1. The Chelyabinsk firework asteroid had a diameter of 20 meters, about 60 feet. The threat is only broken windows. More people died or got badly hurt in traffic accidents in Chelyabinsk that same day.
      http://en.wikipedia.org/wiki/Chelyabinsk_meteor

      During the cold war nuclear weapons were planned to be detonated over the own cities, as air defense against incoming missiles. People would just watch the light phenomena and continue their ordinary lives, as they did in Chelyabinsk. Such tiny rocks aren’t dangerous.

      What we really should worry about in the long term is the comets. While the asteroids can be observed and their trajectories calculated, and work on that is progressing very well, comets hit us from random directions and from outside of our observation horizon and history and often at huge speed. We would need several anti-comet satellites in differently inclined orbits to be able to respond to that threat. Luckily, comet impacts are nowadays much rarer than asteroid impacts. But when we soon will have eliminated the asteroid threat, the comet threat will be a much harder case to crack.

  2. “it could be done for a lot less than we’re wasting on SLS/Orion.”
    But where would be the room for all the graft if actual results are demanded? /sarc

    1. Sounds like a great opportunity for graft to me.


      Homer: Not a bear in sight. The Bear Patrol must be working like a charm.
      Lisa: That’s spacious reasoning, Dad.
      Homer: Thank you, dear.
      Lisa: By your logic I could claim that this rock keeps tigers away.
      Homer: Oh, how does it work?
      Lisa: It doesn’t work.
      Homer: Uh-huh.
      Lisa: It’s just a stupid rock.
      Homer: Uh-huh.
      Lisa: But I don’t see any tigers around, do you?
      [Homer thinks of this, then pulls out some money]
      Homer: Lisa, I want to buy your rock.
      [Lisa refuses at first, then takes the exchange]

      I wonder if Congress is already funding it.

  3. NASA really needs to get serious about this. Sentinel, or something like it, is unimaginably more important than Europa Clipper or another Mars rover. Waiting another few years to find out about billion-year-old clays on Mars, or the depth of Europan ice shell, isn’t the end of the world. On the other hand…

  4. Rickl’s link indicates the major hit rate is 1000 yrs. rather than one million claimed by consensus. This makes more sense when you relate it to the daily event of shooting stars which are not all just grains of sand.

  5. The estimated diameter of this object is 60 feet. That doesn’t sound like much. However, I remember reading about 10 years ago that an impactor 80 feet in diameter would release approximately 1 megaton of energy. An impactor 80 meters in diameter would release about 10 megatons. This one, had it impacted with the Earth and depending on various factors like the relative velocities of it and the Earth and its composition, would likely release about 500 kilotons of energy, give or take. To put that in perspective, the Little Boy bomb dropped on Hiroshima was about 15 kilotons.

  6. “You can always count on Americans to do the right thing – after they’ve tried everything else.” – Winston Churchill

    It usually takes the disaster or reaching the tipping point. A rock has to hit in the U.S. and do so real property damages that threatens the insurance industry to put enough pressure on congress .. et cetera, et cetera…..

    1. It’s not obvious that’s as big an issue as was thought. A rubble pile, which would be sort of a solidish body due to vacuum cementing, could still make a heck of a shockwave, even if there was little or no debris on the ground. The Chelyabinsk meteoroid/asteroid was ~15 m across, but the largest recovered piece was about 1 meter or so, and since it fell in the water, it left no visible crater. Look at Tunguska as another example of a significant event that left no crater.

      We have had two big wake-up calls, SL-9 and Chelyabinsk, and hit “snooze” both times. We won’t be able to say we didn’t have any warning.

  7. And, again, there’s always the possibility of the WarGames / Crimson Tide / 9/26/83 scenario. A meteor that is “only” 60 feet in diameter, if it impacted in the wrong place at the wrong time during a tense moment, could touch off a local or global war based on bad information, especially if we never saw it coming in the first place.

    If the Chelyabinsk meteor had instead impacted in Sevastopol on, say, March 3, 2014, things could have turned really ugly, really quickly.

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