Superbird A timing

Matson, Robert (
Fri, 11 Sep 1998 13:03:49 -0700

Hi All,

I observed Superbird A (#20040, 89041A) from Belmont Shore, CA, last
night (Thursday, September 10th) from about 8:01-8:05 pm PDT (3:01-
3:05 UTC, September 11).  Peak flashes were 1st magnitude, despite
being quite low on the horizon.  Rotational period was measured at
23.143 +/- .014 seconds.  PPAS format info below:

89- 41A 98-09-11 03:05  RM 162.00 0.1  7 23.143  mag +1 --> inv

(Location: 33.7602N, 118.1295W, 5m)

The peak came approximately four minutes earlier than predicted.  I've
adjusted my model accordingly.  For flashes Friday night (September 11),
subtract about 3 minutes from the times I posted for each city in
yesterday's report.  This satellite should now be visible from all 48
contiguous states.  Flashes start in southern California (peaking at
3:02 UT tonite) and end in Maine (peaking at 3:24 UT).  For all locations,
the peak flashes occur at R.A. 22h 52m.  The declination varies depending
on your latitude.  For SoCal, the declination is -11.3 deg.  The higher
your latitude, the lower the declination.  Some other cities:

Houston:  -11.2
Chicago:  -12.7
Washington, D.C.:  -12.5
New York City:  -12.7

If you've never seen a geosynchronous satellite before, I strongly
recommend trying this one!  If weather prevents you from seeing
it Friday night, try looking one minute later on Saturday night, and
one more minute each subsequent night.  The location does not
change that much from night to night.  The declination stays the
same and the right ascension shifts 3 minutes lower each night
(e.g., Washington, D.C. location on Saturday night would be
RA 22h 49m, Dec -12.5 deg).  --Rob