Re: Why is ISS still visible in Earth's shadow?

From: Bob King (nightsky55@gmail.com)
Date: Mon May 02 2011 - 20:10:33 UTC

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    Hi Patrick and all,
    I'm learning a lot here and appreciate your responses. Regarding
    Patrick's deep observations of the ISS, wouldn't it be possible for
    moonshine (earthshine's opposite) to play a role, at least around full
    phase? Could reflected light from the oceans in particular be enough
    to illuminate the station to 11th magnitude or brighter when inside
    the shadow?
    Thanks,
    Bob
    
    On Mon, May 2, 2011 at 1:25 PM, Patrick Schmeer
    <pasc1312-seesat@yahoo.de> wrote:
    > I have followed with my 8" SCT the ISS many
    > times not only for some seconds but up to two
    > or three minutes after entering the Earth's
    > shadow - the apparent magnitude was about 11.
    > For me the only explanation would be
    > artificial light sources (position lights or
    > interior lighting of the ISS).
    >
    > Patrick
    >
    >
    > --- Woodchuk <woodl@telus.net> wrote:
    >
    >> Friday evening using a  12.5" dob I followed
    >> the ISS for several second (about 15) after
    >> it went dark as it passed into Earth's shadow .
    >> It was still faintly visible when I lost it in
    >> the trees. It would take almost a minute for
    >> the ISS to move far enough down range before the
    >> Sun would be 6° below the horizon as seen from ISS
    >> and still within the region of Civil twilight --
    >> as seen on  Earth (as tested using Guide 8). I
    >> think that would still be enough light to
    >> illuminate ISS so it could still be seen in a
    >> telescope at about 100x. Being above the Earth's
    >> atmosphere will change the amount of twilight
    >> but by how much??
    >>
    >> I'm sure the extent of twilight could be checked
    >> on video taken from the ISS.
    >>
    >> Larry Wood
    >>
    >>
    >> On 01/05/2011 6:36 PM, Bob King wrote:
    >> > Hi everyone,
    >> > I've always wanted to ask this question. No
    >> > doubt some of you have followed the space station
    >> > into Earth's shadow, where it's visible for some
    >> > time with binoculars. Is it being illuminated by
    >> > the moon or ???
    >> > Thank you for your help!
    >> > Best wishes,
    >> > Bob
    >
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