You can not see a bright SPOT, but I believe you could spot (!) it. I have once noticed illumination on trees or ground in front of me, and turned around to find a fading Iridium. I also think I've seen reports here on illuminated ground. The "spot" is the base of a cone about 1/2 degree wide, since it is a mirror image of the Sun. This computes to 8 km at a range of about 900 km. But you may have noticed that a flare is still rather bright after one second, so the edges are not sharp. You can inspect output from H-A or IridFlar.exe at various flare distances/flare angles, or simply the length of bright flare tracks, to get a feel for the size. At a peak magnitude of -8.5 it is about 40 times fainter than the full moon, which corresponds to a merely 5+ days old moon! ----- Original Message ----- From: "Art Glick" <omb00900@mail.wvnet.edu> To: <SeeSat-D@satobs.org> Sent: Wednesday, April 18, 2007 5:57 AM Subject: Silly Question > Howdy SeeSatters! > > Here's a silly question. > > If one had a good view of the terrain around them (e.g. from a high > point), and if the actual dead center ground track of an Iridium > reflection passed very close nearby, could one literally see a bright spot > moving across the ground? > > I realize we're talking about a FAST moving reflection! If, for example, > I could see about five miles of ground track at one time from my high > perch, I figure it would traverse from one end to the other in about one > second, but that seems to me to be perceptible. > > Just how illuminated is the ground from a -8 flare? Does anyone know if > there's a concentrated spot of light right down the track? How big would > the spot be? > > Like I said - a silly question? > > Best Regards to All, > > Art > > > > Almost Heaven Group > HC 67 Box 539 BB > Renick WV 24966 > Phone/Fax 304-645-2310 > e-mail art@almostheaven.net > http://www.almostheaven.net/ > > ---------------------------------------------- > Offering direct sales of Saunas, Steamrooms > and the widest selection of Pool, Spa, Sauna > and Hot Tub Equipment worldwide. > > ------------------------------------------------------------------------- > Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: > http://www.satobs.org/seesat/seesatindex.html > ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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