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From: starrfie@hydro.la.asu.edu (Sumner Starrfield)
Subject: HST Mission (fwd) from Bob Williams
Date: Mon, 6 Dec 93 10:39:56 MST
Forwarded message:
>From wms@stsci.edu Mon Dec 6 07:53:55 1993
Date: Mon, 6 Dec 93 10:00:39 EST
From: Robert Williams <wms@stsci.edu>
Message-ID: <vsnet-history1856@hoge.baba.hajime.jp>
To: starrfie@hydro.la.asu.edu
Subject: HST Mission
>From DOXSEY@avion.stsci.edu Mon Dec 6 05:35:09 1993
Subject: HST now has two new Solar Arrays !!
To: wms@stsci.edu, elt@astrovax.princeton.edu, grepass@gsfcmail.nasa.gov,
GILLIL@stsci.edu, weaver@stsci.edu, mcgrath@stsci.edu,
storrs@stsci.edu, ~saha@avion.stsci.edu, mackenty@stsci.edu,
~library@avion.stsci.edu, rjallen@stsci.edu, LONG@stsci.edu,
sbaum@stsci.edu, ford@stsci.edu, SESD@avion.stsci.edu
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SM Report #5
6:00 AM December 06 340:11:00
Summary of recent activities:
EVA #2 has been completed successfully. HST now
has two brand new Solar Arrays.
The EVA crew, Kathy Thornton and Tom Akers,
started the EVA a bit early, leaving the airlock at
about 10:30 pm eastern time. The first task was to
jettison the + solar array, the one which had the
kinked bi-stem. This was accomplished by Kathy
Thornton, riding on the RMS arm, simply releasing
the array, backing away the arm, then backing away
Endeavour. I missed the TV image of the array jettison
but am told that it appeared to "flap away" as the
Endeavour backed away. It has been tracked on radar
and is well separated (more than 20 miles) from the
Endeavour. The EVA crew then installed the new + Wing
with no incidents. They removed the old - Wing and stored
it on the Solar Array carrier in the orbiter bay for
return to earth. They then installed the new - Wing
on the HST. The STOCC at GSFC ran electrical aliveness
tests which were successful. The arrays will remain
stowed until later in the mission.
The EVA crew finished their assigned tasks a
little early and did some preparatory work for tommorrows
EVA. This should give tommorrows EVA crew a head start
on their activities.
During the day yesterday their were several SI
reconfigurations which demonstrated that the fuse plugs
installed on EVA #1 are all working properly.
The SIs are being maintained in a warm state in
preparation for later activities. They seem to be
staying warmer than the thermal models indicated, so several
steps have been taken to keep them from getting too warm.
The GHRS is being kept warm with 3 DEBs on instead of 4.
We have had to do a little balancing act with the WFPC. The
sun has frequently been directly on the radiator. In this
condition the TECs can barely keep the CCDs cold without
violating internal limits. At one point we had to shut
the TECs off for a few hours. Now that the Solar Array
installation has been completed HST is being rotated to
an orientation which should keep the radiator shadowed
enough for temperatures to remain within limits.
Problems/Issues/Changes under consideration:
The GHRS pressure sensor has detected several "pulses"
of pressure over the last two days. The first occurred during
the first EVA while Story Musgrave was in the aft shroud changing
out the RSU assemblies. This was believed to be due to water
from the suit cooling system and should not cause any problems.
The second was during EVA #2 when the Endeavour fired jets and
backed away from the jettisoned solar array. The pressure jumped
up for about three minutes and then dropped back down again. This
has raised some contamination concerns, which are being looked
into by engineers and contamination experts at GSFC and JSC.
The FOS ion gauge has been turned on to provide additional
monitoring of aft shroud internal pressures.
Near-term plans:
EVA #3 is scheduled for tommorrow. This EVA will replace
the WFPC-I with the WFPC-II and will install two replacement
magnetometers.
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
