STS-77 Mission Control Center 
Status Report 9

Thursday, May 23, 1996 7 a.m. CDT

The work aboard the Space Shuttle Endeavour has switched from
rendezvous and proximity operations with satellites to science
gathering aboard an orbiting laboratory.

The six astronauts spent the first half of their workday assisting
payload controllers with investigations into materials processing of
samples and the growth of crystals while documenting the progress of
starfish and mussel development in a spaceborne aquarium in the
Spacehab module in the Shuttle's cargo bay.

The crew was awakened at 11:30 PM Central time last night with a
children's song from Mission Control called "Milky Way". The
crew then moved off in different directions to support work with many
of the experiments that make up the fourth mission of the Spacehab
pressurized module.

Endeavour is about 64 miles away from the Passive Aerodynamically
Stabilized Magnetically Damped Satellite-Satellite Test Unit, or
PAMS-STU, which was deployed from a canister in the payload bay
yesterday.  A small engine firing aboard Endeavour is planned later
this morning to begin the slow re-rendezvous with the satellite
scheduled for Saturday.

This technology demonstration experiment investigates the use of
natural, aerodynamic stabilization to orient a spacecraft properly, a
technique that could prolong the lifetime of future satellites by
reducing or eliminating the requirement for attitude control
propellants.

During the first proximity operations of Endeavour to the satellite, a
strong lock on the satellite using the laser-based tracking
instruments aboard the shuttle was not obtained.  However, two more
close rendezvous operations with the satellite are planned Saturday
and Sunday to check its progress.  Those stationkeeping exercises are
expected to last up to six and a half hours each.

The astronauts also completed an in-flight maintenance procedure to
improve the flow of beverages in a dispenser aboard Endeavour designed
to test the capability of soft drinks to stay cold and carbonated in
weightlessness.

The astronauts will go to bed at 2:30 this afternoon and will wake up
at 10:30 tonight.  Endeavour continue to provide a stable platform for
the science investigations going on around the clock, even while the
crew sleeps.  The orbiter's current altitude is 175 statute miles
with an orbital period of 90 minutes.

The JSC newsroom remains open around the clock during the STS-77 mission.