IML-2 Status Report #20
 
IML-2 Public Affairs Status Report #20
6:00 a.m. CDT, July 18, 1994
9/18:17 MET
Spacelab Mission Operations Control
Marshall Space Flight Center
 
    Mission Specialists Carl Walz, Leroy Chiao and Don Thomas continued to
conduct experiments for the second International Microgravity Laboratory (IML-
2) overnight.  During a live interview with CBS reporters, Don Thomas said the
crew members were spending their scheduled time off with their "faces pressed
up against the window, watching the Earth go by."
 
    While performing a scheduled examination of the Japanese newts container in
the Aquatic Animal Experiment Unit (AAEU), Thomas reported that a second female
adult newt had died.  This Japanese red-bellied newt produced eggs earlier in
the mission as part of an experiment for Dr. Masamichi Yamashita of Kanagawa,
Japan, who is studying the effects of gravity on cells during the early stages
of development.
 
    Principal Investigator Dr. Ken-Ichi Ijiri of Tokyo, Japan, received video
from the Spacelab of his Medaka fish.  Ijiri observed the swimming behavior of
the Medaka and watched the Medaka fry (that were fertilized on Earth and
recently hatched on this flight) as they swam in their own separate containers
within the AAEU aquarium.  Also at the AAEU facility, Chiao opened the window
on the goldfish tank and closed it before his shift ended, giving the goldfish
a daylight period.
 
    In the European Space Agency's Bubble, Drop and Particle Unit, Chiao
initiated an investigation to study evaporation and condensation processes in
fluids.  More specifically, Dr. Johannes Straub, of Munich Germany, examined
the boiling process of a liquid refrigerant. "For the first time, while
watching video from space, we have seen that when two large bubbles join
together, or coalesce, their movements produce new bubbles," explained Straub.
"We are very excited about seeing this phenomenon since we can not do this
experiment on Earth due to the buoyancy of bubbles.  We are extremely pleased
about the way the facility has performed and we appreciate the good job the
crew has done to help us get this science." Knowledge gained from this
investigation could influence future chemical engineering and manufacturing
techniques.
 
    Thomas installed a sample container of indium-gallium-antimony into the
Japanese space agency's Large Isothermal Furnace. This experiment is designed
to help Principal Investigator Dr. Akira Hirata of Tokyo, Japan, develop new
techniques to uniformly mix semiconductor alloys with different densities to
produce materials that will transmit electrons more efficiently.
Semiconductors are widely used in computers and other electronic devices.
 
    In an experiment to separate chromosome DNA from a nematode worm, Thomas
injected concentrated suspensions of the DNA into the Japanese-provided Free
Flow Electrophoresis Unit (FFEU), along with a special buffer solution designed
to test isoelectric focusing.  The FFEU appears to be operating well following
a third inflight maintenance procedure, which was performed by the Red Team
Sunday. Principal Investigator Dr. Hidesaburo Kobayashi of Saitama, Japan, is
testing this method of chromosome separation in space to help solve problems in
genetic mapping and molecular biology.
 
    Chiao monitored the start up of two separate experiments in the
Electromagnetic Containerless Processing Facility (called TEMPUS) last night.
In the first TEMPUS investigation, Principal Investigator Dr. Dieter Herlach
studied a sphere of nickel and carbon alloy, which was undercooled, or
solidified at a temperature below normal for this alloy.
 
    In the second TEMPUS experiment run, Chiao reported on the progress of a
sample of iron and nickel alloy as it was melted, levitated and undercooled for
Principal Investigator Dr. Ivan Egry of Cologne, Germany. Egry is studying
internal friction (viscosity) and the force that keeps a liquid together in a
drop (surface tension).  Although both of these samples made contact with their
cage while processing in the TEMPUS facility last night, ground commanding
allowed them to be successfully retracted from the heating chamber.
 
    Chiao also conducted life science experiments in the Slow Rotating
Centrifuge Microscope facility (called NIZEMI). He placed sample containers of
slime mold (Physarum polycephalum) into the NIZEMI, where they were exposed to
varying levels of gravity.  This investigation will help Dr. Ingrid Block of
Cologne, Germany, understand more about how single-cell organisms sense and
respond to gravity.
 
    In an experiment for Dr. Dieter Volkmann of Bonn, Germany, Chiao placed
seedlings of cress roots into the NIZEMI facility.  Later, Thomas talked to
Volkmann about the growth status of the cress roots.  Volkmann is studying
these chemically prepared cress roots to determine the lowest level at which
the roots become sensitive to changes in gravity.
 
    Thomas placed samples of Loxodes striatus cells into the NIZEMI facility
for an experiment to study the orientation, velocities and swimming tracks of
these unicellular organisms.  Since these cells may work similarly to the inner
ear of vertebrates, Principal Investigator Dr. Ruth Hemmersbach-Krause of
Cologne, Germany, wants to learn more about the underlying mechanisms that
allow living creatures to sense gravity.
 
    In a technology experiment for Principal Investigator Dr. Augusto Cogoli of
Zurich, Switzerland, Thomas took samples of baker's yeast from their containers
and preserved them for post-flight analyses.  This investigation, which studies
the effect of stirring and mixing on the growth of baker's yeast, may influence
the way life science experiments are performed in the future.
 
    While all these activities were going on in space, the Critical Point
Facility science team in the Spacelab Mission Operations Control center in
Huntsville watched video downlink of the sulfur hexafluoride sample as it was
heated to reach its critical point (the state of a fluid at which liquid and
vapor exhibit the same properties).
 
    During the next 12 hours, the crew will spend time in the Lower Body
Negative Pressure device and continue life and materials science
investigations.
 
 
NASA issues four status reports daily on STS-65/IML-2 activities: science
operations reports from Spacelab Mission Operations Control in Huntsville at
approximately 6 a.m. and 6 p.m., and orbiter operations reports from Mission
Control in Houston at approximately 8 a.m. and 5 p.m.