STS-72 Mission Status Report # 7
Mission Control Center

Monday, Jan. 15, 7 a.m. CST

Astronauts Leroy Chiao and Dan Barry spent more than six hours in
Endeavour's cargo bay this morning, conducting the first of two
spacewalks on the STS-72 mission to test tools and techniques which
may be used in the construction of the International Space Station.

With Winston Scott acting as the spacewalk coordinator from the aft
flight deck, Chiao and Barry floated out of Endeavour's airlock at
11:35 Sunday night to begin the 31st spacewalk in Shuttle history.

After taking a few minutes to acclimate themselves in the payload bay,
first-time spacewalkers Chiao and Barry attached a portable work
platform to the end of the robot arm, operated by Pilot Brent Jett and
Mission Specialist Koichi Wakata.  Jett used the arm to grapple
various pieces of hardware designed to hold large modular components,
mimicking the way equipment boxes and avionics gear will be moved back
and forth in assembling the Space Station.

Chiao and Barry unfolded a cable tray diagonally across the forward
portion of the cargo bay housing simulated electrical and fluid lines
similar to those which will connect modules and nodes of the Space
Station.  The rigid umbilical, as it is known, was tested for its ease
of handling and the ability of the astronauts to hook up the lines to
connectors on the side of Endeavour's bay.

While Chiao unraveled various lengths of cable from a caddy device,
Barry spent time practicing the hookup of the various cables in the
rigid umbilical to connectors in the bay, testing his ability to
manipulate tiny bolts and screws in weightlessness.  He reported that
most tasks could be accomplished with little difficulty.  Barry and
Chiao then traded places, as Barry mounted the portable work platform
to evaluate its worth.

The astronauts stayed ahead of their timeline throughout the night,
finally concluding their spacewalk at 5:44 Monday morning.  In all,
Chiao and Barry spent six hours and nine minutes in the cargo bay.

Throughout the spacewalk, flight controllers kept tabs on the
temperature of thruster fuel lines in the Japanese Space Flyer Unit
satellite, which was retrieved Saturday by Wakata.  Fluctuating
temperatures in the fuel lines, possibly caused by the erratic
performance of the SFU's thermostats, resulted in the development
of a series of procedures for reorientating the Shuttle to warm up the
satellite, if required, to prevent hydrazine in the thruster lines
from freezing.

The astronauts were awakened Sunday night at 6:41 to the theme from
"Star Trek, The Next Generation."  Within hours, the astronauts began
a series of jet thruster firings to increase the distance between
Endeavour and the OAST-Flyer science satellite which Wakata deployed
Sunday.  The satellite is scheduled to be retrieved tomorrow morning.

Endeavour is orbiting the Earth every 90 minutes at an altitude of 192
statute miles with all of its systems in excellent shape.  The next
status report will be issued Tuesday morning. The JSC newsroom will
close at 11 today and will reopen at 11 tonight.