STS-77 Re-entry

Michael P. Murphy (murph@erinet.com)
Sun, 2 Jun 1996 09:29:07 -0400

Hello Everyone!

 Friday, May 24th, I was informed by my boss that I would have to travel to
Farmington, New Mexico, USA to assist in the start up of one of our new
engine installations in the gas fields.  At first, I thought that I would
not have a chance to see any of the STS-77 visual passes that were upcoming
in my part of the USA, central Ohio.  Our weather had been poor throughout
the mission, and passes up to that point had been wiped out by clouds.

 I saw Gil Carman's re-entry track listing, and noticed that Durango,
Colorado was scheduled to get an almost overhead pass of the orbiter during
entry.  Well, Durango is not far from Farmington, so early Wednesday morning
(4:00 AM local), a co-worker and I piled into the car and headed north.  We
stopped about 12 miles (19 Km) south of Durango, as it took longer than
expected to drive through Farmington itself.  We left a little late as well,
trying to confirm the fact that the de-orbit burn had occurred for a landing
in Florida.

 On top of a hill at about 10:48 GMT, we had perfect viewing condidions, the
sky was very clear, with steady conditions.  Very few lights were around in
the surrounding country, but the sky was brightening due to twilight.  My
friend first saw the Endeavour come over a mountain range in the west.  What
a sight!  The orbiter was in the midst of a very bright spot showing a
pinkish hue, followed by a brilliant white ion trail about 3 degrees long.
I'm not sure what the magnitude of the orbiter and plasma, it was very
bright!  Behind the glowing ion trail was what looked like a smoke trail,
probably being illuminated by sunlight, as the sun was only 10 degrees below
the horizon.

 Near maximum elevation, the front of this spectacle looked like the coma of
a comet through binoculars, the orbiter buried in brilliant pinkish white
plasma, and the trail eminating from the coma pinching down before spreading
as it was left behind.  A very impressive sight indeed!  Maximum elevation
was lower and earlier then predicted. 

  Talking with Gil Carman that evening, he said that the orbiter had
maintained station keeping with the small sub satellite longer than
expected, causing higher drag than predicted.  Eventually, this affected the
entry interface time and ground track for re-entry.  Even though it did not
go directly overhead, a 60 degree elevation pass was still impressive!

 Three and a half minutes after highest elevation, the sonic boom was heard
as a soft, muffled report, like that of a large muzzle loading cannon heard
from a few miles away.  The boom echoed off of nearby mountain ranges,
leading to multiple reports being heard in quick order, coming from many
different directions.  The smoke trail lasted about seven minutes before
dissipating.  We noticed several "kinks" in the smoke trail, as if the
orbiter was making course corrections on the way into KSC.  Both kinks were
corrections to the right of course, maybe a few degrees each.  Otherwise,
the trail looked very straight, from horizon to horizon.

 I was really lucky to be sent into the right location at the right time!
Also, I did not have to pay for the trip, as I was working there!  Sure
makes up for all of the nice passes missed due to weather!  If anyone ever
has the chance to see a shuttle entry, I highly recommend trying to observe
the event.  You won't see many things in the sky as impressive as an orbiter
during entry!  (Launches are awesome as well!)

 Thanks for your attention, I thought everyone would like to read about an
unexpected observation of the re-entry.


Mike Murphy
Springfield, Ohio... USA