Not all of the research on MSL-1 fits
nicely into the categories of "Metals and Alloys Research," "Biotechnology
/ Protein Crystal Growth," or "Combustion Science." But these
experiments are still extremely important to the overall science
program on this mission. Today we feature these experiments that are on
the à la Carte science menu. Like a good restaurant, those
items featured here are every bit as scientifically appetizing as those
items listed as entrees on the menu.
The arrangement
of atoms in a solid, how they get to be arranged in this way, and how their
arrangements affect the overall properties of the material are areas of
great interest in materials science and fluid physics. Properties such as
strength, flexibility, and electrical conductivity of a solid are all related
to how the atoms are arranged. Many high-technology processes related to
optical coatings or semiconductors involve the layering of atoms or molecules
in a particular order or structure atop a substrate. The more we can learn
about how these processes occur, the better equipped we are to potentially
influence their happenings to generate more useful materials.
The Physics of
Hard Spheres Experiment uses tiny hard spheres
as a model to study the transition between liquid and solid phases that
actually takes place on the atomic level. Although easier to study than
individual atoms themselves, the hard-sphere model is much more profoundly
influenced by gravity. By flying the experiment on the shuttle, scientists
are better equipped to study the physics of these liquid-solid systems,
using the easier representation of the hard spheres, without the detrimental
interference of gravity. The picture at left shows how hard spheres arrange
themselves in the different phases and the concentrations at which they
occur on Earth. Click on the picture for a full diagram.
NASA has performed
many life-science or biological experiments aboard the space shuttle in
the past, and MSL-1, although not primarily dedicated to these science areas,
continues this program with the Astro/Plant
Generic Bioprocessing Apparatus (Astro/PGBA).
This experiment is being conducted to study how particular plant systems
adapt to spaceflight, especially the production of the plants structural
elements, secondary products that are often used as pharmaceuticals, and
the alterations in sugars and starches. The picture shows the plants inside
the PGBA growth chamber from Spacehab mission in May, 1996
Fluid Physics is one of the main areas of research within NASA's Microgravity Science Program. As you might expect, fluids behave very differently in the absence of gravity compared to what we observe normally on the ground. Rivers flow downhill because of gravity, milk pours onto cereal in the morning because of gravity, and the liquid in your drink takes on the shape of the glass because of gravity. On MSL-1, there are three experiments dedictated to furthering our knowledge and understanding of how fluids behave in the microgravity environment, and to study fluid processes that are otherwise masked by gravity's pervasive influence.
we do these experiments
in space!!! 
we do these experiments
in space!!! 
June 19, 1997
Author: Dr.
John Horack
Curator:Linda Porter
NASA Official: Gregory
S. Wilson