NOTICE:  NASA DAILY WILL NOT PUBLISH ON JULY 3, WE WILL RESUME ON JULY 6.

	Daily                News
Thursday, July 2, 1992  24-hour audio service at 202/755-1788

 % Orbiting Spacelab crew continues to provide fundamental new data;
 % University of Wisconsin plant growth unit activated by crew;
 % Orbiter regenerative carbon dioxide scrubber remains functional;
 % Commander Richards puts Columbia through redundant systems test;
 % STS-50 mission passes half-way point P Crew and vehicle in excellent shape;
 % Orbiter Atlantis assigned to Palmdale following next flight for rebuild work.

* * * * * * * * * * * * * * * *

The orbiting team of microgravity experimenters aboard Columbia
continued yesterday and throughout the night to press forward through
the mission's multiple investigations -- all being performed with
visual and voice links to their ground-based principal investigator
teams.  Payload specialist Gene Trinh spent eight hours during his last
shift performing the second set of experiments in the Surface Tension
Driven Convection experiment.  These experiments are aimed at
determining the effects of internal and surface heating on fluid
motion.  In order to trace the motions, the silicon oil samples being
heated have aluminum oxide tracer particles imbedded in them and are
being illuminated by a laser in order to highlight the fluid motion.
The team for this set of experiments is from Case Western Reserve
University and the Lewis Research Center.  Following the mission, the
team expects to be able to correlate the observed fluid motion with
their computer models and to then refine the model of thermocapillary
flow.

In another set of fundamental physics experiments, mission specialist
Carl Meade performed a set of Wire Insulation Flammability experiments
which Lewis investigator Greenberg described as being potentially very
useful in allowing for better detection, control and abatement of
fire.  The experiment is one of several aimed at determining the
fundamental physics and chemistry associated with combustion.

While the Spacelab module crew was performing their materials and
physics experiments, mission specialist Ellen Baker was activating the
Astroculture plant nutrient device in Columbia's mid-deck.  This
experiment is the first in a series of on-orbit tests to evaluate a set
of subsystems which can maintain plants in a microgravity environment.
This first unit will test only the water-delivery aspect of plant
growth units.  On subsequent flights, lighting and atmospheric control
aspects of a plant growth system will also be tested.  Investigator
Robert Morrow, University of Wisconsin, said his team wants to make
sure each element of the developmental system is tested independently
and shown to work in microgravity so they can separate gravitational
effects from other plant-growth variables such as temperature and light
levels.  The Wisconsin team's ultimate aim is to design and deliver a
technology base for a sophisticated plant growth facility which could
act as a life support system.

Although the Astroculture experiment has long-term implications for
possible use on a space station or planetary base, the newly-repaired
Regenerative Carbon Dioxide Removal System has a possible shorter-term
advantage in weight and stowage space savings for use on future shuttle
flights and possibly incorporation into atmospheric subsystems aboard
Space Station Freedom.  Ever since pilot Ken Bowersox rewired the
faulty sensor logic unit on Tuesday, the unit has been performing
properly and is continuing in its function to scrub Columbia's cabin
air.

The STS-50 mission passed the half-way point in the mission's planned
13-day duration shortly before midnight last night .  With 104 orbits
behind them, flight crew commander Dick Richards put Columbia through a
planned redundant component checkout test and confirmed the operability
of the orbiter's onboard functional elements.  Houston flight
controllers report that from their perspective Columbia is performing
superbly and the vehicle and crew remain in excellent condition.

* * * * * * * * * * * * * * * *

The shuttle Atlantis, Orbiter Vehicle 104, will be returned to the
Rockwell International Space Division facility at Palmdale, Calif.,
following the upcoming STS-46 Tethered Satellite System mission.
Atlantis will undergo a series of planned equipment upgrades and
systems inspections which is performed on each of the orbiters every
three years.  Discovery, OV-103, is currently undergoing just such
maintenance activity in one of the Orbiter Processing Facilities at the
Kennedy Space Center.  Shuttle Director Tom Utsman said the decision to
send Atlantis back to Palmdale will enable the KSC work flow to be more
focused on preparing shuttles for flight.  The decision to keep
Palmdale active also allows NASA to maintain a skilled and highly
effective work force at Rockwell's Palmdale facility.  Utsman said that
keeping Palmdale active will also allow the agency to integrate a
Russian automated rendezvous and docking mechanism should the ongoing
U.S.-Russian space activity negotiations prove fruitful.  The decision
to perform the Atlantis work in California will not cause any jobs to
be lost in Florida, Utsman noted.

* * * * * * * * * * * * * * * *
  
Here's the broadcast schedule for Public Affairs events on NASA Select
TV.  Note that all events and times may change without notice, and that
all times listed are Eastern.  Live indicates a program is transmitted
live.

Thursday, July 2, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live    2:00 pm  Today in Space report on the progress of the  USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
        9:00 pm  Replay of Today in Space program from earlier.

Friday, July 3, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live   10:00 am  Live coverage of the SAMPEX launch aboard a multi-stage Scout
                 vehicle from Vandenberg Air Force Base, Calif., begins.
Live   10:19 am  Scheduled launch of the Solar Anomalous and Magnetospheric
                 Particle Explorer on a Scout rocket from LSC-5 at VAFB.
Live    2:00 pm  Today in Space report on the progress of the USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
                 9:00 pm  Replay of Today in Space program from earlier.

Saturday, July 4, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live    2:00 pm  Today in Space report on the progress of the USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
        9:00 pm  Replay of Today in Space program from earlier.

Sunday, July 5, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live    2:00 pm  Today in Space report on the progress of the USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
        9:00 pm  Replay of Today in Space program from earlier.

Monday, July 6, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live    2:00 pm  Today in Space report on the progress of the USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
        9:00 pm  Replay of Today in Space program from earlier.

Tuesday, July 7, 1992
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
Live    6:57 am  STS-50 flight crew in-flight press conference from Spacelab
                 module aboard Columbia.
Live    2:00 pm  Today in Space report on the progress of the USML-1 mission.
Live    3:00 pm  Mission status briefing on crew, orbiter and Spacelab systems.
Live   Throughout the day, live experiment video and crew activity from crew
                 cabin and Spacelab module aboard Columbia.
        9:00 pm  Replay of Today in Space program from earlier.

Wednesday, July 8, 1992
Live    1:27 am  Deactivation activities to place Spacelab module and
                 experiments in stowed position for end of mission.
Live    3:39 am  Preparations for deorbit maneuver of Columbia.
Live    7:35 am  Deorbit maneuver to place Columbia in proper trajectory for
                 landing at Edwards Air Force Base.
Live    8:35 am  Landing of Columbia at Edwards Air Force Base, California.
TBD              Replay of landing scenes.
Live  TBD        Post-landing press conference from Multi-use Facility at
                 Dryden Flight Research Facility, Edwards, Calif.
  
This report is filed daily at noon, Monday through Friday.  It is a
service of NASA's Office of Public Affairs.  The editor is Charles
Redmond, 202/453-8425 or CREDMOND on NASAmail.  NASA Select TV is
carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees West
Longitude, transponder frequency is 3960 MegaHertz, audio subcarrier is
6.8 MHz, polarization is vertical.