BRIGHT tether!

Robert Reeves (
Sun, 10 Mar 1996 10:11:08 -0600

I have been an astronomer for 40 years and a satellite observer for 36.  I
really got into satellite observing while under the wing of fellow San
Antonio resident, Paul Maley, while we were both still in high school here
in Texas in 1961.  In all the years since, I have not seen a satellite pass
to compare with this morning's TSS pass over San Antonio, Texas.  It was
stunning!  I am still amazed after thinking about it for four hours.

Paul, you didn't have to go all the way to Australia to see this amazing
sight. A seat on my backyard deck was all you needed! <G>

For a change, the early morning weather cooperated.  Normally, this locale
is cloudy in the early AM.  Instead it was very dry, not too cool, no wind,
very clear except for the moon which blocked the view of the comet.  Even in
this deep urban location, I could see third mag. stars in spite of the moon.

TSS popped out of the shadow at 5:53 AM, local time and lit up like a neon
sign. It was fully three degrees long with the TSS itself easily visible as
a 3 to 3.5 mag point of light at the upper end of the bluish-gray tether.
The tether was angled at a position angle (to local vertical) of about 220
degrees and at the lower (snapped-off) end was a noticable condensation of
light.  It was obviously coiled slightly at the free end.

With my attention rivetted to the sight in my 7X35 binoculars, I only took
one quick glance at the thing with my naked eye.  In spite of the nearby
gibbous moon, the TSS and tether was very visible from my location deep
within urvan city limits.  I would estimate the magnitude of the tether
along any "point souce" location of its extended length as 4.5 to 5 mag.
The cumulative magnitude of the entire strand, the TSS, and the knot at the
free end probably combined to magnitude zero or brighter.  I am a poor
magnitude guesser and tend to err on the side of too bright when I make
closer comparisons to star cahrts.  But still, the thing was a whopper to
the naked eye.  Couldn't miss it.  It was like a flying knitting needle.

As TSS reached culmination (71 degrees), it was noticably forshortened to
about a two degree length, but it remained very bright and extremely
straight.  Its linear straightness was a surprise.  I didn't know if I could
even see the thing beforehand, and I was expecting it to be bowed down and
forward of the TSS's direction of travel.  I was delighted to find it is
easily visible and straight as an arrow.

I am assuming that for the tether to be so visible, it must be coiled like a
telephone cord and have more "width" than just the 2.5 mm thickness of the cord.

As TSS approached the eastern horizon, the sun phase became quite bad, but
the tether remained visible to the naked eye just as it hit my 30 degree
elevation tree line in the east.  At this point, the position angle had
swung down to about 185 degrees and the tether again extended about three
degrees across the field of my binoculars.

Doing a mental model of the pass and visualizing what I saw by using a
pencil as a simulator, it looked to me like the tether is angled down and
forward of the TSS's direction of travel, extending straight at an angle of
about 30 degrees from vertical (or 60 degrees down from TSS's horizontal to
Earth's surface below).

All in all, quite a sight.  Move heaven and earth if you can to see this

Robert Reeves      
520 Rittiman Rd.             210-828-9036
San Antonio, Texas  78209