NASA’s Glenn Research Center Ties to Upcoming Space Shuttle Launch

When space shuttle mission STS-127 launches on June 13, there will be connections to NASA’s Glenn Research Center both in the shuttle bay and on the ground. In the bay will be the next phase of the Binary Colloidal Alloy Test (BCAT-5) and spare nickel-hydrogen battery Orbital Replacement Units.

The BCAT-5 is the next step in an ongoing experiment being conducted aboard the International Space Station. It consists of 10 samples contained within a small case the size of a school textbook. After the experiment is set up on station, software will take digital photographs of samples at close range. The images record the rate of phase separation and crystal growth.

The photographs then are downlinked to investigators where they become time-elapsed movies for scientific analysis. Researchers at Harvard University, New York University, University of Pennsylvania, Simon Frazer University in Canada and the Proctor and Gamble Company use this data to refine models about the performance of colloids. Colloids are a broad class of consumer and engineered products including paint, plastics, food, cosmetics and medicines that change state over time.

Performing these experiments on the space station is important because these separation and crystal growth processes occur much more slowly in the microgravity environment and reveal the subtle second order effects such as surface tension and particle jamming that cannot easily be observed on Earth. Small refinements to commercial processes can produce multimillion-dollar cost savings to U.S. industry or create the fundamental understanding for new materials.

Among the studies that BCAT-5 will support, two have direct applications on Earth:

* Phase separation rates that affect product shelf life could prove useful to consumer product companies such as Proctor and Gamble in Ohio.
* Modeling the competition between phase separation and crystallization is important in the manufacture of plastics and other materials.

The six spare nickel-hydrogen battery Orbital Replacement Units (ORUs) that will be delivered to the space station will replace existing battery ORUs that have been on station 9.5 years and are approaching their end of life. The batteries are components of the complex electric power system (EPS) aboard station that provides all the power necessary for the continuous, reliable operation of the spacecraft. The electric power system consists of several hardware components called ORUs. Each, including the batteries, is considered a subsystem of the entire EPS and can be replaced upon failure either robotically or by extravehicular activity. These components work together to provide power generation, power distribution and energy storage for the space station.

The batteries are one of the most important ORUs in the electric power system. Efficient energy storage is vital since the space station must use stored solar energy to power itself during the 35 minutes of each orbit that the station is in Earth’s shadow. Due to the station orbit, this results in a total of 16 battery charge/discharge cycles per day.

NASA’s Glenn Research Center leads the sustaining engineering and subsystem integration and management of EPS hardware including the integration of space station’s international partners’ modules. On the ground, Glenn engineers will support the battery replacement and start-up from the Mission Evaluation Room at NASA’s Johnson Space Center during the STS-127 mission.

Also at Johnson Space Center during each shuttle mission, several Glenn engineers, working with other NASA engineers, directly support prelaunch, launch and landing operations. Some are monitoring the shuttle’s Purge, Vent and Drain Subsystem, which is vital to stabilizing the shuttle’s pressure and temperature before, during and after landing. Others are working to ensure the structure of the shuttle orbiter remains safe throughout the flight.