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Will the Earth's Tail Fry Moon Visitors?

Roland Piquepaille writes "Researchers working for NASA's Lunar Reconnaissance Orbiter mission have discovered that the Earth's magnetic tail could be harmful to future astronauts. The moon stays inside Earth's 'magnetotail' for six days every month — during full moon. This can have consequences ranging from lunar 'dust storms' to strong electrostatic discharges, according to one researcher quoted by NASA in 'The Moon and the Magnetotail.' So far, this is pure speculation: no man has been on the moon when the magnetotail hits. As added the same scientist, 'Apollo astronauts never landed on a full moon and they never experienced the magnetotail.' But read more for additional details about how Earth's magnetotail could affect men on the moon."

8 of 166 comments (clear)

  1. Not every month by Geoffrey.landis · · Score: 4, Informative

    Actually, the moon doesn't pass through Earth's magnetotail every month-- the moon's orbit is inclined to the ecliptic, so some months the magnetotail passes north or south of the moon-- it depends on season and precession.

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    1. Re:Not every month by spazdor · · Score: 3, Informative

      Quite right. Otherwise there'd be a lunar and a solar eclipse every month.

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    2. Re:Not every month by Anonymous Coward · · Score: 4, Informative

      Even the most conservative estimate indicates the moon always passes through the magnetotail, because the earth's magnetotail is much larger than the earth's shadow. Here's my calculation. If I made a mistake, please correct me.

      The Magnetotail is 20-25 Re(earth radii) across depending on season(minimum 10 Re in radius); much bigger than the shadow of the earth(2 Re). The moon's orbit is inclined 5% off the ecliptic(the plane of earth's orbit around the sun). The earth's magnetotail is essentially in this plane. The moon is at a distance of 405696 km at apogee (~60 Re). This means even at the point when the moon is furthest from the ecliptic plane (ie apogee is coaligned with the magnetotail) it will still fall inside the magnetotail.

      60.24 * sin((5./180)*pi) = 5.25 Re < 10 Re

      Thus, precession or no, the moon will always be in the magnetotail for at least part of each orbit. It would take extremely extraordinary(read: improbable) solar wind conditions to make the magnetotail thin to 5 Re.

  2. Re:Full Moon on Moon? by frovingslosh · · Score: 4, Informative

    No, it would be a "new Earth", which happens from the moon's viewpoint when Earth sees a full moon. A full Earth, from the moon's viewpoint, would happen two weeks later when the moon is "new" and not in the tail at all. Since a "new Earth" and a "full moon" happen at the same time, the full moon reference is perfectly correct and makes more sense.

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  3. Ahem by dreamchaser · · Score: 4, Informative

    Just one example of what might go on that we can't see with regards to lunar dust storms. Took me all of a few seconds to find and there looks to be a lot more to read. Google is your friend.

  4. Roland the Plogger again by Animats · · Score: 5, Informative

    It's Roland the Plogger, wrong as usual.

    It's not like this is a newly discovered phenomenon. After all, there have been many unmanned moon landings and equipment has operated through the "magnetotail" many times. The USSR landed two lunar rovers, both of which worked for months. Lunokhod 1 was operational for 322 days, and Lunokhod 2 was operational for about four months. This was in the early 1970s.

    1. Re:Roland the Plogger again by 1u3hr · · Score: 5, Informative
      And Roland got his "for more information" link to his blog through again. Recently the editors have omitted these (though if you look in the firehose, Roland puts his spammy blog link in every submission).

      Tagged "blogspam" and "fuckroland".

  5. This was brought up in 1956 then 2005: by Fluffeh · · Score: 5, Informative

    A detailed look at this can be found in this link from Nasa on the topic of moon fountains, which is basically the exact same thing under a different name.

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