One clarification on USA 32 and 81 is that my experience is that the wild sparkling can happen when the satellite is between Sun and observer (large phase angle) as well as when the phase angle is small. Perhaps this may mean that the sparkling is from a surface that is not particularly phase-angle dependent? Anyway, just a few hours ago USA 32 sparkled wildly on an evening pass here that culminated at altitude 39, azimuth 268 at about 4:12:26 UTC (May 27), soon before shadow entry. In this case I believe it occurred before culmination, which is why I tried to suggest before that at least it does this mad flashing after culmination, but I didn't mean to say that it doesn't do it at other points during some passes. My understand of USA 129 flares and flashes has been that they are somewhat analogous to those exhibited from time to time by the Hubble Space Telescope. That is, they have to do with an active payload being pointed in different directions at different times, so that the orientations of the specular surfaces vary widely. Here in Austin a few hours ago USA 129 did a couple of bright flashes; as it exited the Earth's shadow it was at least +1; then it dimmed briefly and then flashed quickly to at least +1 again. A few weeks ago Björn Gimle reported a near -8 flash followed by a -1 flash: http://www2.satellite.eu.org/seesat/Apr-2001/0287.html The MCF size unit of the large balloons was indeed million cubic feet, according to this page: http://master.nsbf.nasa.gov/fred/mission1.html Another page has a graphic illustrating the size of such large balloons at launch and at mission altitude: http://topweb.gsfc.nasa.gov/balloon/inside.html They are something like 100 meters in diameter when inflated -- large enough to contain a Boeing 747 with room to spare! 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
This archive was generated by hypermail 2b29 : Sat May 26 2001 - 01:04:05 PDT