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NASA Meteoroid-Spotting Program Captures Brightest-Yet Moon Impact

Posted by timothy on from the look-exclusively-on-the-bright-side dept.

From a NASA press release published Friday: "For the past 8 years, NASA astronomers have been monitoring the Moon for signs of explosions caused by meteoroids hitting the lunar surface. 'Lunar meteor showers' have turned out to be more common than anyone expected, with hundreds of detectable impacts occurring every year. They've just seen the biggest explosion in the history of the program." Watch the flash for yourself.

11 of 66 comments (clear)

  1. C'mon NASA, get your act together on units by femtobyte · · Score: 5, Interesting

    "On March 17, 2013, an object about the size of a small boulder hit the lunar surface in Mare Imbrium," says Bill Cooke of NASA's Meteoroid Environment Office.

    "size of a small boulder"? This has to be one of the most useless size descriptions possible (I suppose they could have said "the size of a random rock"). Given that they later indicate

    The 40 kg meteoroid measuring 0.3 to 0.4 meters wide

    it's not as if they shouldn't have been able to come up with a more descriptive metaphor.

    1. Re:C'mon NASA, get your act together on units by ColdWetDog · · Score: 3, Funny

      Where's the kaboom? You call that an earth shattering kaboom?

      Oh. Wait.

      I

      --
      Faster! Faster! Faster would be better!
    2. Re:C'mon NASA, get your act together on units by wvmarle · · Score: 2

      Where's the kaboom? You call that an earth shattering kaboom?

      Oh. Wait.

      I

      It's on the moon, silly. That should be a "moon shattering kaboom". And it seems on-one has ever heard one of those, so we don't know how they sound like.

    3. Re:C'mon NASA, get your act together on units by femtobyte · · Score: 3, Insightful

      Granted, at that point they were talking about not staying out in a meteor shower if you're *on the moon*. That might be more appropriate advice than on Earth --- it's the atmosphere that keeps people safe from being killed by the average 40 tons a day of space debris raining down on the planet. Staying a bit less exposed won't protect you from a 5-ton hit, but it might keep you from getting punctured by some pea-sized shrapnel arriving at far higher than normal frequency in the same debris clusters with 40cm chunks.

    4. Re:C'mon NASA, get your act together on units by DNS-and-BIND · · Score: 2

      Am I the only one who finds the inevitable unit flame in NASA stories not only tiresome but cliche?

      --
      Shutting down free speech with violence isn't fighting fascism. It IS fascism!
    5. Re:C'mon NASA, get your act together on units by jamesh · · Score: 4, Interesting

      "On March 17, 2013, an object about the size of a small boulder hit the lunar surface in Mare Imbrium," says Bill Cooke of NASA's Meteoroid Environment Office.

      "size of a small boulder"? This has to be one of the most useless size descriptions possible (I suppose they could have said "the size of a random rock"). Given that they later indicate

      The 40 kg meteoroid measuring 0.3 to 0.4 meters wide

      it's not as if they shouldn't have been able to come up with a more descriptive metaphor.

      That bothered me less than the fact that in the same sentence they describe its size and mass in metric units but its speed in imperial units.

    6. Re:C'mon NASA, get your act together on units by jamesh · · Score: 2

      Where's the kaboom? You call that an earth shattering kaboom?

      Oh. Wait.

      I

      It's on the moon, silly. That should be a "moon shattering kaboom". And it seems on-one has ever heard one of those, so we don't know how they sound like.

      I was thinking about this. On the next trip to the moon they should stick a few seismic monitoring devices around the place. From that they could synthesize some audio which would make that youtube video a bit more exciting, and start a few flame wars on why there is audio at all from people who don't read tfs.

    7. Re:C'mon NASA, get your act together on units by cusco · · Score: 2

      Penetrators with seismographs have been developed for for use on Mars missions, and then cancelled several times. It should be possible to adapt them for lunar use.

      'Lunar meteor showers' have turned out to be more common than anyone expected

      I find this a bit worrying. When Comet Shoemaker-Levy hit Jupiter it was estimated to be a once in a century or more event, but since then marks left behind by at least two and possibly three other strikes have been seen. I wonder if estimates for the amount of material drifting around the solar system aren't considerably off.

      --
      "Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
    8. Re:C'mon NASA, get your act together on units by RockDoctor · · Score: 2
      In this context, I read "boulder" as being a technical term, from the list of sediment grain size classes. The largest class of sediment grains is "boulder", at sizes greater than 256mm (yes, it's a power-of-two scale) ; so a "small boulder" is something not far above this boundary condition.

      "small boulder" is completely the correct term to use. Just because it sounds like the talk you'd hear on the street, doesn't mean that it's not a precisely worded technical description.

      (Yes, I am a geologist, and yes, I do use this size scale every working day of my life.)

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  2. Re:So what substance exploded? by Bieeanda · · Score: 4, Informative
    The original article addresses this in a footnote:

    The Moon has no oxygen atmosphere, so how can something explode? Lunar meteors don't require oxygen or combustion to make themselves visible. They hit the ground with so much kinetic energy that even a pebble can make a crater several feet wide. The flash of light comes not from combustion but rather from the thermal glow of molten rock and hot vapors at the impact site.

  3. Re:That's what you get by femtobyte · · Score: 2

    Earth's atmospheric pressure at sea level is roughly equivalent to having ~10m of water (1g/cm^3 density) above our heads. At a density of ~1.5g/cm^3, and a thickness between 5 and 10m, lunar regolith is in many areas equivalent to *less* mass than the atmosphere protecting our heads. That "solid rock" might be a bit less tough than you think compared to the crazy big chunk of air covering us on Earth.