Re: Ian Porter, Jean Monseur, Observing

bjorn@tt-tech.se
Thu, 6 Jun 1996 11:45:31 +0100

From: b_gimle@algonet.se (Bjoern Gimle)
Subject: Re: 1996-029A/C obs

Jean Monseur wrote:

>For the moment I am just trying to catch answers to faq
>about the observation techniques..

Ian Porter wrote:

>I observed 96-29A about 5 deg below Atria,
..
>Then the bright object starts to diverge ! "Thats not right"
..
>rejected as a viewing object because its pass time was too close to
>the Navy Sats and I had not bothered to check its star track !
>
>As an aside, can anyone give me some tips on equipment and techniques

Is Atria a constellation, or an Arabic star name ? Though Rob Matson's
SkyMap has a two way star name file, I prefer Greek star names.
(or coordinates) When I searched for Atria, I found alp (alpha) Tri.

Here are my observing hints. Don't miss the bottom lines !

Use a graphic program like SkyMap to show/print the tracks of possibly
distracting objects in the intended observation area/time frame.

Since SkyMap also has high precision zooming and coordinate readout,
it can also be used to convert visual observations to coordinates.
If you have a reasonably accurate elset for the object, you can also
check the lap times, to make sure you haven't mis-identified any
reference star.

When finding an unknown, a good trick for memory and later analysis,
is to keep the binoculars steady, count or measure by stopwatch the
time it takes the satellite from rim (or center) to rim of the field-
of-view, and the direction of exit ( up as 12h or 000 degrees, right
as 3h or 090 degrees)
"It passed from center of my 7.1 degree field on June 04,1996 at
08:22:33.4 UT, to the rim in 8.4 seconds, and exited in direction 120  =20
degrees"

Of course a position indication, as accurate as possible, is also  =20
required.
RA, dec preferred, alt/az or star reference is also possible.

For accurate position/time measurements, use a line between two stars and
estimate the fraction by which the track splits the line.

You can also use the angle between the line and the track for the
direction/speed estimate.

Use a stopwatch with at least 4 lap memories to avoid having to read the
watch and make notes for each point. Use a tape recorder if you can't
make notes after a few positions, or your memory is short.
At least 20 lap memories if you see more than object before making notes,
and 100 for flash measurements.

If you have enough lap memories, record some times from an accurate time
source before and after the passes. Otherwise, keep a SW radio at hand.
  =20

Last but not least, read the www pages of the Belgian Working Group for  =20
Satellites:

http://www.physics.ox.ac.uk/sat/observe.html

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