RE: Solar sailing vs. laws of physics ?

From: Adrian Tymes (wingcat@pacbell.net)
Date: Wed Jul 02 2003 - 22:24:59 MDT

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    --- Spike <spike66@comcast.net> wrote:
    > > Solar sailing breaks laws of physics
    > >
    >
    http://www.eurekalert.org/pub_releases/2003-07/ns-ssb070203.php
    >
    >
    > >1. Photons themselves have temperature? Shyeah,
    > right.
    >
    > They are talking about Boltzmann temperature,
    > Adrian.
    > The energy of a photon is E=h(nu) where nu is the
    > frequency. Then you can convert the energy to an
    > equivalent temperature by using the Boltzmann's
    > constant,
    > which is (I think) about 1.4E-23 newton-meters per
    > kelvin.

    Agreed: *equivalent* temperature, derived from energy
    of the photon, is affected. But that's not quite the
    same thing.

    > >2. Photons aren't the only thing these sails may
    > >reflect. Ever heard of the "solar wind"? That's
    > made
    > >of particles.
    >
    > Nah, solar wind particles pass right thru the sail
    > as if nothing is there. Wouldn't even slow em
    > down. spike

    Some is deflected. Maybe a very miniscule amount.
    I'm
    not necesarily saying this is even a significant part
    of the overall system, just that it's nonzero.

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