1. Bird. Only a few hours after looking at the lunar transit movie, on TV I saw some video of a reddened setting (or rising) Sun, and in the distance some birds flew in front of it. They were easily distinguishable as birds but were quite small against the solar disk. The main problem would seem to be the length of time to transit the disk, but perhaps an oblique flight path would help that hypothesis. On quite a few occasions I've seen birds flying over at night; it's easy to see them when you're in the middle of a city and they're well illuminated from below. In Austin we have a colony of hundreds of thousands of bats, and I've seen them on occasion cross my binocular field, but obviously they were close enough to distinguish between bat and bird. I don't think that I've ever knowingly seen an insect in the same way.) 2. Satellite. I'm going to try to stretch my very weak geometry muscles, and use very round numbers. Please expect errors! ... If an object subtends 1/500 of the lunar disk, at lunar distance it's roughly 7 km or 7000 meters in diameter (asteroid size). At 1/1000 lunar distance (about 385 km), it's 7 meters in diameter (satellite size). (By the way, at 3.85 km range it's 7 centimeters in diameter ... I think! -- hummingbird or other very small bird size.) 3. At what range would a nearly point-sized object on a perpendicular path take 24 seconds to transit one-half degree? 4. I wonder about monitor size and display resolution -- how they affect the clarity of the lunar transit movie. On mine at work, 15-inch, 800x600 resolution, I could not discern any particular shape but only that it seemed to be extended and seemed to be varying irregularly -- and that there were those faint, quickly fading after-images behind it part of the time. 5. Is any more information available on the lunar transit movie -- date and time, observer's location? Ed Cannon - ecannon@mail.utexas.edu - Austin, Texas, USA ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
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