They also are melting metals and then rapidly cooling them to study the transformation from liquid to solid states. Scientists hope this will lead to the production of high-quality metal alloys. Another experiment uses the weightless environment in the shuttle to suspend liquid drops by sound waves. Researchers hope this technique can be used on Earth to facilitate sanitary, containerless packaging of chemicals, cosmetics and food. Researchers on Earth, who are monitoring the experiments, are able to give the astronauts feedback on how the experiments are progressing.
Astronauts can then adjust their techniques to improve results.
Voss said people's ability to react to unplanned situations is what makes human spaceflight desirable compared to unmanned missions, such as the Mars Pathfinder landing scheduled for today. Although the astronauts said they don't mind being in orbit during the July Fourth Pathfinder landing, a girl from the Victorville School District was concerned about their holiday celebration. She asked if they had apple pie on board for their Independence Day meal.