I neglected to mention that USA 129 currently in visible in evening in the Southern Hemisphere, at latitudes south of about 30 S. Here are a few tips on how to conduct the search. 1. Run predictions for both of the elsets that I provided. 2. Note that elset 71004 produces the earliest likely pass; 71001, the latest. 3. Note also that the two paths will be different, but roughly parallel, This is the result of Earth's rotation relative the orbit. 4. To estimate the object's path for times between the passes predicted by elsets 71004 and 71001, simply interpolate between the paths of those passes. For example, if the object arrives mid-way between the 71004 and 71001 predicted times, then it will be mid-way between their paths, and parallel to them. 5. The object will be near apogee when it passes, so it is a good idea to use binoculars, unless the pass is high and your sky dark. 6. If you do use binoculars, be careful to keep the predicted path in your field of view, as discussed in number 4 above. 7. When you start observing, have a clear notion of the object's expected path, to help you to avoid following the wrong object. 8. Please report negative observations (non-sightings), including the search time, sky conditions, limiting magnitude, optics used. 8. When you see the object, try to time its passage between a pair of stars that you can later identify on a star chart. Or time its closest approach to a single star, estimating how far above/below/left/right it passed. Even a rough position and time is helpful when a satellite is recovered, so don't allow inexperience to discourage you from trying. To improve your prospects of producing at least a rough measurement, when planning your observations, look for a pair of stars, or a line of several stars, lying perpendicular to the predicted track(s). Be prepared to time the passage of the satellite as it passes between one of the star pairs, noting its fractional distance between star A and B, i.e. 20 percent from A to B. Be sure to report the RA and Dec coordinates of both stars, and the epoch of the star chart on which they were drawn. For rough observations, try to use star pairs no more than 5 to 10 deg apart. The closer the better. You will need a way to calibrate your wristwatch or stopwatch to UTC, to about 1 s for rough obs. You will also need to report your site co-ordinates, ideally to 100 m accuracy. It is preferable to report to the list, but if you prefer confidentiality, please report directly to me. Additional information on how to make positional observations is available here: http://satobs.org/position/posn_measure.html http://satobs.org/faq/Chapter-07.txt Ted Molczan ----------------------------------------------------------------- To unsubscribe from SeeSat-L, send a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@satobs.org List archived at http://www.satobs.org/seesat/seesatindex.html
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