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UPDATE # 33 - January 10, 1998 PART 1: Get involved in Space Team Online GET INVOLVED IN SPACE TEAM ONLINE
Happy New Year from Space Team Online! If you are a teacher and haven't yet gotten your students involved in Space Team Online projects, we hope this is the year you will start. Below are two activities that won't require too much planning or time. First, consider joining a web chat. For one hour, NASA experts are available to talk about their jobs and how they wound up working for NASA. A different person joins us almost every week. Please visit this page for details: http://quest.arc.nasa.gov/space/events/interact.html This Wednesday at 10AM Pacific, Tracy Gill will be in the chat room. Tracy works to prepare experiments to fly on the shuttle. He has provided a biography and a bunch of Field Journals and now will be your chance to ask him questions. For more about Tracy, please read his biography at http://quest.arc.nasa.gov/space/team/gill.html * * * * * * * * * * * * * * * * * * * * * * * * * Another activity is called Student Stumper will work on the communication skills of students while challenging them to think creatively. The basic idea is this: kids make riddles for other kids to solve. Students will create a question about the shuttle or space station that they think will be difficult but fun to answer. Pose that question (we'll put it online in the Kids' Corner of the Web), and others will email their responses directly back. The question creator gets to decide if the respondent is right. Then, we'd love to see the results if you'd like to share. An example question might be: What are some reasons that the Shuttle's external tank is ejected and not carried for the entire mission. That question isn't too tough; we know you can do better than that! We expect the result to be a bunch of kid-kid email exchanges which heat up the Internet. Send your original Student Stumpers to Oran at oran@quest.arc.nasa.gov. Also, visit the web at http://quest.arc.nasa.gov/space/kids/stumpers.html [Editor's note: Dale is a chemist at the Kennedy Space Center. His group manages over thirty projects involving ground support for the shuttle, space station and expendable vehicle processing and preparation for launch.] CHEMISTRY HELPS IMPROVE KSC'S ENVIRONMENT
Dale Lueck http://quest.arc.nasa.gov/space/team/lueck.html January 8, 1998 It has been a long journey, but we have arrived at phase five of the Nitrogen Oxide (NOx) Scrubber to Fertilizer project. This project has been a three-year team effort to find a way to minimize the Nitrogen Oxide emissions that occur when refueling the space shuttle and Titan rockets. It is interesting to note that the Titan rocket carries a much larger fuel load than the space shuttle! Here is how it works: during refueling operations, it is normal that nitrogen oxide fumes are produced, because the oxidizer (which is called nitrogen tetroxide) is near it's boiling point at room temperature. As the fuel tanks are cooled, more fumes are emitted. The oxidizer fumes (nitrogen oxide) must be contained and filtered so that they don't enter the atmosphere. Filtering these fumes is called scrubbing. The oxidizer scrubber is the equipment that is used to do this. In the current scrubber, as the nitrogen oxide is contained and scrubbed, sodium nitrate and nitric oxide are produced. These are called the liquor. We discovered that using hydrogen peroxide instead of sodium hydroxide in the scrubber produced a byproduct of potassium nitrate - a directly usable fertilizer! To learn more about the chemical process and how the control mechanism works, go to: http://technology.ksc.nasa.gov/WWWaccess/Opport/scrubber.html There are many benefits to this project. The first benefit is to the environment. The old system produced approximately 250,000 pounds per year of highly caustic hazardous waste. Companies had to be contracted to remove the spent liquor and it had to go through a neutralization process, both of which are very expensive. The byproduct of the new scrubbing process is potassium nitrate. Potassium nitrate is a common fertilizer sold in garden care stores throughout the world. The second benefit is that the new scrubber process is approximately five (5) times more efficient in terms of scrubbing the NOx emissions. The third benefit is to the workers safety. Because the liquor is no longer caustic, the workers can handle the waste (potassium nitrate) in a much safer manner, using far less protective gear. The fourth benefit is cost. This process is cost effective because companies will no longer have to be contracted for the removal of the liquor. This saves approximately $65,000 per year. It also reduces the cost of ground maintenance for Kennedy Space Center because the potassium nitrate can be used directly on the grounds at Kennedy Space Center as fertilizer. This saves approximately $18,000 per year. Kennedy Space Center saves a total of $83,000 per year! How did we get here? The project was broken down into five phases: Phase I - Our research was laboratory tested to prove that the concept was valid. Phase II - The process was applied to a full-scale oxidizer scrubber at the "Oxidizer Storage Farm" at launch pad 39A. Phase III - This phase redesigned the process control system and tested the ability of the scrubber to produce potassium nitrate during an operation. Phase IV - This phase is the final field testing of the equipment. Because of the high concentrations involved in the Titan qualification testing, favorable wind conditions are required. Phase V - This is the installation phase of the project. Both the United States Air Force and NASA need the phase IV data to decide if the installation costs are worth the benefits. It is the hope of NASA that this application will be used by industry and will contribute to a safer, less costly and environmentally friendlier world! [Editor's note: Stephanie is an experiment integration engineer. She interprets electrical schematics and writes test procedures to test all the experiment power cables to make sure that they were built correctly. In this series, Stephanie is sharing her experience with CHeX, an experiment that flew recently in space. CHeX involves studying Helium at very specific temperatures. Last time, the Shuttle had just taken off and an early problem with CHeX was fixed by turning the experiment off and back on.] Stephanie Stilson MEASURING ONE TENTH OF ONE BILLIONTH OF ONE DEGREE November 20, 1997 (Flight Day 2) It is 7:30 p.m. and time for work. During my shift, CHeX completed the High Resolution Thermometer (HRT) calibration. A portion of this calibration included performing Flight Objective-2 (FO-2) which involves injecting a bubble into the helium to help give more accurate temperature data. The biggest excitement so far is that by completing the HRT calibration, we have been able to achieve the highest resolution temperature measurements ever attempted in space, one tenth of one billionth of one degree. This is equivalent to the ability to measure the distance between Los Angeles and New York to the width of a single strand of hair! Calibration efforts are continuing. We are about nine hours behind schedule due to being too warm when the mission started. The Payload Experiment Developers (PEDs) assure me that there was nothing we could have done on the ground that would have prevented this situation. Being behind schedule does not pose any impact at this time. November 21, 1997 (Flight Day 3) During my off-shift, the team ran into a slight problem. When one of the valves was commanded open to assist with the cryostat cooling process, there didn't seem to be any change in the rate of temperature drop. The valve open command was reissued with the hopes that although the telemetry reported it open on the initial attempt maybe the mechanical action did not occur. This troubleshooting did not have any affect. The cryogenics team believes that there may be some blockage in one of the cooling loops and is now analyzing data to see if they can figure out exactly where the blockage is located. This problem will not deter us from achieving our science goals, but is will increase the amount of time it takes to get into position to start gathering this data. The bigger hurtle for us right now has to do with the SPARTAN satellite problems. With the plan to grapple SPARTAN in the near future, JSC is requiring the orbiter to use the primary thrusters more often than planned (possibly the remainder of the mission) in order to save fuel. If these thrusters are fired when CHeX is at the lambda point, the cryostat heats up and we slip away from lambda. It would then take us approximately eight hours to recover and we would not be able to achieve the minimum science requirements. Negotiations with JSC are currently underway to come up with a plan that will be acceptable to both CHeX and SPARTAN. Keep your fingers crossed! November 22, 1997 (Flight Day 4) CHeX completed the calibration of the calorimeter heaters and has begun the general scan in preparation for high resolution measurements later in the mission. When the general scans were complete, CHeX began high resolution data collection. The wide range heat capacity measurements were successfully performed and included the first scan above the lambda point. This produced the first observations of the confinement effect in the helium sample. A total of nine high resolution sweeps were completed. CHeX's achievement of today's science objectives was in part due to JSC's minimal use of the orbiter's primary thrusters. We hope that our luck continues. STATUS OF COLUMBIA PROCESSING
Below, we'll provide some details about the post flight work being done after STS-87 and the subsequent processing of Columbia as it prepares to fly again as STS-90. These reports will contain jargon and unfamiliar terms; our intent is not to confuse you, but to provide a glimpse at all the steps involved. Detailed daily reports about Columbia's processing can be found at the NASA Shuttle Status web site at http://www-pao.ksc.nasa.gov/kscpao/status/status.htm Since the last updates-sto message, opened Shuttle Columbia's payload bay doors were opened following an extended down period during the holidays. Ku band antenna testing took place and the orbiterUs nose and main landing gear tires were also installed. The orbiter windows were polished and post-flight window inspections were completed. Technicians replaced fuel cells No.1 and No. 3 and functional tests were begun. Also started were operations to remove the remote manipulator system robotic arm, functional tests of the orbiter maneuvering system, and auxiliary power unit leak and functional checks. STS-90 SCHEDULED OPERATIONAL MILESTONES (dates are target only): - Fuel cell voltage tests complete (Jan. 13)
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