[meteorite-list] UA Science Team Readies For NEAR Landing

From: Stuart Forbes <stuart.forbes_at_meteoritecentral.com>
Date: Thu Apr 22 09:41:07 2004
Message-ID: <004b01c09195$c4885ec0$471abc3e_at_oemcomputer>

>I think you forget that Eros is substantially larger than a Gemini
spacecraft,
>and thus has substantially more gravity. NEAR will be doing a soft crash
>landing on Eros, and it is not going to bounce off. The real issue is
>in what kind of position will the the spacecraft be in after landing (and
yes,
>it can fall over), and will it survive the landing. The spacecraft will be
>hitting the surface at a velocity ranging from 3 meters/second to 6
meters/second.

No, I know Eros has more gravity, but that changes nothing, as I never
mentioned escape velocity (and Gene Cernan was attached by an umbilical,
making a substitute for stronger gravity, he only ever went so far out
before coming back in again). I can't believe the surface gravity is enough
to immediately counteract a velocity of 3 - 6 m/s, even if some energy will
be lost to friction. It will bounce, but that doesn't mean it will bounce at
escape velocity (the fact its descending after a de-orbit burn pretty much
precludes this happening anyway). It will come back (spinning randomly) and
bounce several times, and maybe in several pieces, but it will bounce
without something to hold it down. The idea of it falling over after landing
seems a bit of a strange concept, as its not going to land in any kind of
"straight-up" position.

Regards,

Stuart Forbes
Edinburgh, Scotland
stuart.forbes_at_dial.pipex.com
Received on Thu 08 Feb 2001 01:09:54 AM PST