> How do you know where (exactly) to look? Do you use > detailed star charts of the geo arc and then predict > their location in right ascension and declination? What > programs provide sat locations in RA and declination? > Are there any Geo Flasher programs out there yet? For RA+Dec predictions I use Mike McCants' Highfly program, which is available in DOS (Windows) and Linux/Unix and can be downloaded via this page: http://users2.ev1.net/~mmccants/programs/ This VSOHP page has a lot of information on programs for various platforms: http://www2.satellite.eu.org/tletools.html An important distinction is whether or not you want to use graphical predictions. Highfly produces tabular output. For orbital data I use Mike McCants' geo.tle file available here: http://users2.ev1.net/~mmccants/tles/ I use star charts to get oriented on the Clarke belt, which from here is centered on declination -5. I start with Wil Tirion's Bright Star Atlas, which is in coordinates of 2000. When the sky is very nice, I add some star charts with stars to about +7.5 which are in coordinates of 1950. Since my predictions are for 2000 RA and Dec, it's not quite perfect, but having found the location with the Bright Star Atlas, by comparing it with the fainter ones, it's a workable method for use with 10x50 binoculars at least. I never did decide if it was better to try to scan along the entire belt or just to follow one known RA+Dec area as it passed by them one by one. It was certainly necessary to become familiar with at least a few asterisms on the declination, in order to be able to notice something not belonging. (It's a bit of a problem when with 10x50 I can see stars fainter than +7.5, but if the satellite is +6, it's soon easy to see that the stars are passing by it. By the way, I "discovered" a too-bright star not on the charts, and several SeeSat folks informed me right away that it was Uranus!) For flashing geosynchs, in order to get predictions for them, I give the known ones a "fake magnitude" in the magnitude file that goes with Highfly. But you can look for them any time of year. > I'm just curious if I'll be able to see any in the Seattle > area. Flashing geosynchs, I'd say yes, anytime of year. Look for Superbird A in the next few weeks, as it drifts from Europe over here. Some of the Gorizonts seem to flash for hours each night. (Superbird A and some others flash for only a few minutes per night.) The flaring phenomenon is latitude-dependent, twice per year around the equinoxes. Now, by the way, I should say that all of this is easier if you're using a telescope! Last October, when Mike McCants returned to town and went after them with his 8-inch scope, we were able to see some as faint as +10 or +11, sometimes three or four in the field at once. By then the Moon was past first quarter. Mounted binoculars would be easier also -- holding binocs for two or three minutes isn't easy, in my experience. But it's fun to see them! 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 : Sun Mar 04 2001 - 23:10:43 PST