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Space Moon NASA

NASA Meteoroid-Spotting Program Captures Brightest-Yet Moon Impact 66

Posted by timothy 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.
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NASA Meteoroid-Spotting Program Captures Brightest-Yet Moon Impact More

NASA Meteoroid-Spotting Program Captures Brightest-Yet Moon Impact

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  • Moon terrorists! Quick, let's send everyone from DHS to the Moon!

  • C'mon NASA, get your act together on units (Score:5, Interesting)

    by femtobyte ( 710429 ) on Friday May 17, 2013 @10:33PM (#43759909)

    "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.

    • Re:C'mon NASA, get your act together on units (Score:4, Funny)

      by ColdWetDog ( 752185 ) on Friday May 17, 2013 @10:36PM (#43759917) Homepage

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

      Oh. Wait.

      I

      • 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.

        • Re: (Score:3)

          by jamesh ( 87723 )

          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.

          • Re: (Score:2)

            by Nutria ( 679911 )

            Fortunately, NASA already did that...

            http://www.lpi.usra.edu/lunar/missions/apollo/apollo_15/experiments/ps/ [usra.edu]

            • Unfortunately, they stopped transmitting in 1977 (so no useful information to correlate with today's more advanced remote sensing capabilities). Either a few more (simple) landers are in order, or perhaps we could get some seismic information from laser interferometry off the the corner-cube reflectors we left on the moon (from an Earth-orbiting satellite with an *incredibly fast* fringe counter --- looks hard with today's technology, but perhaps not *that* far away to measure shifts to the O(10GHz) varying

              • Re: (Score:3)

                by cusco ( 717999 )
                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 o

                • 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

                  .

                  Sad that Galileo's antenna didn't open. Headed towards Jupiter it was in a position to film the comet pieces as they hit
                  http://en.wikipedia.org/wiki/Galileo_(spacecraft)#Main_antenna_failure [wikipedia.org]

                  Now that would of been very cool to of seen.

                  I wonder if estimates for the amount of material drifting around the solar system aren't considerably off

                  .

                  Think we've been seeing this from Russian dash cams. But those who gave us the numbers also claim Jupiter's gravity
                  protects Earth to a great extent.

              • I am pretty sure the seismic gear was shut down remotely to save money on the ground.

                • Re: (Score:1)

                  by Anonymous Coward

                  The PSE was part of ALSEP, a package/system used on all the later Apollo missions that had several experiments all connected to a central transmitter and power source (although a few would use their own power sources). By 1977, pretty much all of them had only one or two experiments still working, and they struggled to provided power to both the transmitter and the experiments at the same time. The older 2 of the 4 PSEs were only partially operating. It was predicted there would only be enough power to p

      • No kaboom here. No sound propagation in vacuum. Only thru the lunar soil itself. Standing on the Moon you might feel it from your boots but you wouldn't hear it.

    • Re: (Score:2, Interesting)

      by wvmarle ( 1070040 )

      What stroke me more is at the end of the video they suggest to stay indoors during meteor showers.

      I'd say the risk of your bulding being struck is higher than that of a space-walking astroaut, due to the larger area. And such a 5-ton-TNT hit is a pretty devastating blow to pretty much anything we can build. That is, unless they'd go deep underground (for more reasons than meteorites a good idea).

      • Re:C'mon NASA, get your act together on units (Score:4, Insightful)

        by femtobyte ( 710429 ) on Friday May 17, 2013 @10:55PM (#43759973)

        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.

    • Not sure 'boulder' quite qualifies as a metaphor, especially in that we're talking about the same thing, rocks. I was taught that metaphor was used to describe one thing in terms of another, disparate, thing. "A rock the size of a ship" could be a metaphor, for instance.

      As for size, I wonder if that might not be generational or possibly geographical. When I was a lad, there were rocks. Unless specified or implied by context, rocks were usually something that one might readily pick up. Boulder, on the o

      • 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

        • Had no idea there was a geologists' definition for this. Thanks! But I think your reply ought more correctly be to femtobyte. I take note that my seat of the pants experiential take wasn't so far off, and I stand by my stating that "small boulder" is not a metaphor but rather a simple description.

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

      • I'll admit my "units" dig was somewhat of a worn-out trollish dig. However, the substance of the criticism --- poor science reporting for engaging the general public --- remains. NASA is usually pretty good at relaying scientific information to a general public audience; I'd expect better than this type of unhelpful jargon (correct using a technical definition of boulder at slightly larger than 10 inches / 25cm, but pretty useless to most readers). Clarity in communications is a major part of the *job* of t

        • Perhaps "a small boulder" is a better metaphor than "a 40kg rock of 0.3 meters"? Maybe NASA is trying to get to a different audience than JUST YOU? You're not "most readers" and what you want is irrelevant.

    • Re:C'mon NASA, get your act together on units (Score:5, Interesting)

      by jamesh ( 87723 ) on Friday May 17, 2013 @11:42PM (#43760145)

      "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.

    • And shape of a mashed potato.

    • I'm more thrown off by the tone of the narration in the video. The way she talks in a monotonous tone through the whole thing and the way she adds "he said/she said" to attribute a quotation sounded off because there was no pause or change in tone between it and the quotation itself. I felt like I was in school again listening to some home-made video on lunar impacts by a teacher who has never read lines aloud before.

    • Normal people, who have experience with the outdoors, have no trouble with such a comparison.

    • Re: (Score:2)

      by ignavus ( 213578 )

      "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

      That all depends. Was it a metric boulder (usually measured in liths, like microlith - very small boulder - or megalith - huge rectangular boulder that causes evolutionary changes) or was it an imperial boulder?

      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.

      Ah, 40 kg - it was a metric boulder.

    • "size of a small boulder"? This has to be one of the most useless size descriptions

      NASA message is intended to be delivered to anybody, not only the /. geeks. While we (/. geeks) are used to numbers and proportions, a "small boulder" - while less accurate - is represented better by most people than 0.634124 meter.

    • Re: (Score:2)

      by Jmc23 ( 2353706 )
      Is it a metaphor? Or maybe, just maybe, boulder has a scientific definition that you are ignorant of?
  • Impact kinetic effects are not the same as an explosion. What substances explode on the moon and why didn't that happen when we sent landing crafts over? Could the entire moon explode if a bigger asteroid hits it?

    • Re: (Score:1)

      by Anonymous Coward

      >Impact kinetic effects are not the same as an explosion.

      Physics, you fail it.

      Hit a piece of metal with a hammer and it will heat up; a well known physics demonstration. Slam a meteor into the ground hard enough and it will get so hot it becomes a gas. And what is an explosion but a rapidly expanding ball of hot gases?

    • An explosion is a rapid increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases.

      --Wikipedia (not the final word on technical sources; feel free to reply with a more definitive description)

      The impact converts the massive kinetic energy of fast-moving space items into a lot of localized *friggin' hot* material: the white-hot flash that you see in the video, as the lunar surface is explosively vaporized into a blast of ionized plasma. Impact kinetic effects (with enough energy) *are* very similar to an explosion from some other source releasing similar energy. When we send landing crafts,

    • Re:So what substance exploded? (Score:5, Informative)

      by Bieeanda ( 961632 ) on Friday May 17, 2013 @11:55PM (#43760185)
      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.

    • Could the entire moon explode if a bigger asteroid hits it?

      Yes, but the ass would have to be on some killer steroids.

  • ... the Ides of March!
  • when you don't have an atmosphere.

    Moon, didn't you know it is your right to have an atmosphere. How dare anyone deny you your right to defend yourself. Who will you sue for damages? Your face has been forever changed and someone else must pay for that!

    • Moon, didn't you know it is your right to have an atmosphere.

      The moon's atmosphere is made of regolith, You insensitive clod! Solid rock strata means its stratosphere is a lot tougher than ours!

      • 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 [nasa.gov] 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.

  • It's amazing how much miscellaneous rock is floating around this solar system. Four sizable chunks of rock (tens of meters) have gone by the earth in the last week, one within lunar orbit. None were known objects.

    There's a mile-sized one going by on March 31st, but closest approach is over 3 million miles.

  • Anyone know how big of an impact to the Moon could be a hazard to Earth (for example, from ejected material).

    • You're envisaging that an impact on the Moon causes enough mass of ejecta that the amount impinging on the Earth's atmosphere is enough to do ... something significant? Or that a single impactor of sufficient size is ejected from the lunar impact which could then impact on a city/ county/ state/ country/ continent and obliterate it?

      The latter case is pretty implausible : you'd want an ejectum of several kilometres diameter to be a worthwhile opponent. The 50-odd metres of the Barringer impactor really isn'

  • I told him and TOLD him, not to text while approaching the base .. but nooo ...

    Toad

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