Stephan Szyman wrote: >on 3 oct there will be an annular eclipse for central spain at 08:58 UT, >will the sky darken enough at the peak of the event to allow for naked-eye >observations of LEO objects? A few replies on the list already stated that the sky during an annular eclipse is too bright to see LEO's (other than very bright flares). But if you are in NE America the sky is still dark enough to see satellites. Projected to a surface 800 km above the Earth (where many bright LEO objects are located) the central line of the eclipse extends westward via Newfoundland toward the Great Lakes. Here are the UTC times and geographic positions where an annular eclipse would be visible in 800 km altitude: 8:28 46.21N 42.50W 8:30 46.22N 51.86W 8:32 45.99N 57.81W 8:34 45.67N 62.60W 8:36 45.31N 66.75W 8:38 44.92N 70.46W 8:40 44.52N 73.86W 8:42 44.10N 77.02W LEO's passing close to those sites at the given times would experience an annular or deep partial eclipse lasting just a few minutes. But they have to be quite close (in time and space) to the above sites for a visual observer to clearly identify this change in brightness because at the same time the magnitude of the satellite changes due to phase angle, distance etc. >if not, would someone kindly kick me a list of predictions? ( I noticed >mr. holtkamp has offered to do so for geostationary objects.) I'll prepare a prediction for the geostationary objects by mid-week. Just so much for now: Geostationary satellites close to 28.6 deg East will experience a TOTAL eclipse at 9:49 UT (at the same time that observers on the ground see an annular eclipse - the GEOs are closer to the Moon). But those satellites are on the daylight side of the Earth at the time and can not be observed. But on the opposite side of the Earth around 13:32 UTC there will be an annular eclipse for GEOs at 140.9 East. Australia, New Zealand and East Asia would be good places for observing that under dark skies. Gerhard HOLTKAMP Darmstadt, Germany ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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