re: Flashing geosat

From: Walter Nissen <dk058_at_cleveland.Freenet.Edu>
Date: Fri, 28 Apr 1995 10:31:27 -0400

> Fm: J. Thomas Jeffrey 73220,2435

> Tonight I was able to see the satellite INTSAT 2-2 dX ... .
> I used Traksat 2.8 to predict it's
> position. I then plotted the position using Uranometria 2000.

> Using my 14 inch telescope with a low power eyepiece (giving a magnification
> of 44X) I was able to see the satellite.

Congratulations on this OBS.

I am reluctant to say something, but as the references become multiple, no
one else speaks up and the latest is redistributed by Bart, I feel
compelled to do so. I am not sure if the program Traksat 2.8 is the same
as a program for PCs called TrakSat 2.80. The latter program is widely
available. It is at one and the same time both delightful and troubling.
Among its disadvantages, a major one for visual observers is that it has
only the vaguest idea where the shadow is, making it (to the best of my
knowledge) unreliable for calcuations such as the one cited. For LEOs,
some people like to use QuickSat to generate observing opportunities and
then use the planetarium display in TrakSat to find the satellites. For
GEOs, I suppose Highfly would substitute for QuickSat, and then you
probably need an atlas or accurate setting circles.

Geostationary satellites are indeed visible with a 14" (350mm), even from
a metropolitan area. The most favorable time is within a week of the
times the declination of the sun is the same as that of the Clarke belt as
seen from your site (latitude), i.e., times which are a while before the
vernal equinox and a while after the autumnal equinox. As Victor
Slabinski and I discovered at Hopewell Observatory in Haymarket, Virginia,
two decades ago, (he was looking at the printout from his program and
directing my use of a C8), then they can be easily seen in a small
telescope at about magnitude 10. The visual effect of a river of stars
streaming past the stationary bright point is quite striking. The effect
can be varied by switching the clock drive on and off. As pointed out by
Leith Holloway, they transit the Great Nebula in Orion, M42, as seen from
the latitude of the middle of the U.S. Incidently, it is Victor Slabinski
who figures out what commands should be sent to all Intelsats to place
them in their orbits and maintain them on station, so if I understand that
you saw an Intelsat (I don't recognize your nomenclature), in a way, you
observed his handiwork.

Cheers.

P.S. for Bart and Bjoern: It wouldn't matter whether I recognized the
vulgar name, if the US SPACECOM catalog number had been provided.

P.P.S. (presumed response from Bart and Bjoern, or at least someone on
their side of the pond): It wouldn't matter whether you recognized the
vulgar name, if the COSPAR ID had been provided.

P.P.P.S.: I've already spoken about names. I'm very unhappy. I'd
desperately like to get rid of two of the three systems. I haven't the
slightest idea how to do that. As an accommodation to the existing
situation, I make a strong effort, not always successful, to mention all
three whenever I mention any one. When Europeans (who devised the
similarly arcane X.400 addressing scheme) use only the COSPAR ID (which
looks like Greek to me), I end up annotating their work with either the
vulgar name or the catalog number; which is a real annoyance in Flash.

P.P.P.P.S.: NORAD is the former name of US SPACECOM (U.S. Space Command).
Perhaps its use survives for the same reasons I sometimes use "thot"
instead of "thought".

P.P.P.P.P.S.: If you like the tumbling of 23550 = 1995-18B = Ofeq 3 r,
check out 23405 = 1994-77B = C* 2297 r when you get the chance. Or,
19210 = 1988-50A = C* 1953.

P.P.P.P.P.P.S.: If the COSPAR ID is to be used, it would help if somebody
could decide whether to write 88-50A or 88-050A or 1988-050A or 1988-050 A
or 88050A or 1988050A. Is there a standard? If so, is anybody optimistic
about it ever being widely acceptable?

---
Thomas Paine's "The Age of Reason" is a great read.
Received on Fri Apr 28 1995 - 13:45:32 UTC

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