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UPDATE # 34 - Janaury 16, 1998PART 1: Shuttle Simulation activity
The "Shuttle Simulation" activity is preparing for blastoff. "Shuttle Simulation" has students pretending they are conducting their own in-class space shuttle mission. Youngsters will first perform a launch simulation with a NASA-provided script. Next, while "on-orbit," an experiment will be conducted, collecting real data. To complete the mission, a landing simulation will occur. Classrooms will be then be teamed with others to share the numerical data gathered and draw conclusions. This will work best at the elementary/middle-school levels. Teachers have flexibility about when they schedule their mission, but several classrooms are now on the launch pad, about ready to begin. Please consider joining us. For more information, visit: http://quest.arc.nasa.gov/space/events/simulations SPACE STATION VIDEOCONFERENCE
On February 19, a videoconference called "Space Station: Countdown to Launch" will be broadcast at 12:30-2:00 p.m. Eastern. The program is designed for students in grades 5-12 and will be delivered via satellite TV and the Internet. This exciting telecast will give students and educators an inside look at the ISS. Countdown to Launch will fire studentsŐ interest in careers in scientific and technical fields as they hear from and even interact with the people who are making ISS a reality. With a diverse panel of top NASA, university, and other experts, this live, interactive, ninety-minute program will put you directly in touch with the scientists, engineers and astronauts who are helping to build and use the International Space Station. In addition, another videoconference is scheduled for February 26 from 1-3 p.m. Eastern. This second program will be far more technical then the first and is designed for professionals interested in Space Station research plans; college students and faculty are also encouraged to participate. If you intend to participate via satellite television, you must first register. Until January 22, the simple registration is free. If you plan to take part via the Internet, more details will be available in several weeks on NASA's Learning Technologies Channel. For further information, please visit the Web site at: http://centauri.larc.nasa.gov/station.html [Editor's note: Emily figures out how to make stuff (the technical term for this is material processing). Her team group has worked on problems like how to make thin glass fibers used for optical cable or how to pour molten metal without forming bubbles of gas in it. Most problems have to do with what happens when some sort of fluid becomes a solid. Emily works to simulate these processes on a computer.] A FANCY WAY TO MAKE ODD-SHAPED OBJECTS
Emily Nelson http://quest.arc.nasa.gov/space/team/nelson.html January 9, l998 We would like to develop new materials for high-speed aircraft that are lighter, more durable, and able to tolerate high temperatures. I'm looking at the manufacture of ceramic composites (composite just means a combination), such as silicon carbide, which is made up of the elements silicon and carbon. I'm performing an experiment of "near net-shape modeling" of parts. Suppose that we wanted to make a square block of silicon carbide but with a huge hole straight through the center of it. One way that we could make it is to make a block of silicon carbide and then drill a cylindrical hole in it. But that means that we waste all the material that used to be silicon carbide and is now the hole. Plus, silicon carbide is pretty brittle, so that we might crack a few dozen of these blocks before we got a good one. That's pretty wasteful, and waste means that it is expensive. So, one of the things we're investigating is "near-net shape manufacturing." That means that we start out with something that is easy to shape. Then, we turn that material into the material that we want. No, we don't use a magic wand. Here's what we do for silicon carbide: we take graphite (carbon) powder and mix it with a special type of alcohol; this creates a gunky mushy blob of stuff that we can pour into molds. Then we heat up the gunky mush. This causes the alcohol to evaporate, leaving the pure carbon in a glasslike state. The carbon is no longer a powder; it's now a solid which is in the shape of the mold. But this glasslike carbon has little tiny holes all over the place where the alcohol used to be -- it's what we call a porous material. (Ever look at a sugar cube? That's a porous material, too -- it's got little holes in between all the sugar crystals.) Then we place one edge of the carbon in contact with liquid silicon, and something really cool happens. The liquid silicon is sucked up into the hole-y carbon by a process called wicking, which is caused by the presence of all the little holes in the carbon. (Try this experiment: put one little corner of a sugar cube into a cup of tea and hold it there. You will be able to see the tea fill all the available extra space in the sugar cube. That's wicking.) Then, a chemical reaction takes place between the silicon and the carbon, causing silicon carbide to form, and it is in the shape of the original glasslike carbon. Voila! No waste! I'm developing a computer program to model this process for my Ph.D. thesis at the University of California at Berkeley.) [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 experiment had completed nine successful measurements.] Stephanie Stilson GETTING GOOD DATA AND OBTAINING COMMAND WINDOWS November 23, 1997 (Flight Day 5) Things are going well for the CHeX. A total of 21 high resolution data scans have been completed and the data shows a clear confinement signal as well as the bulk transition marker. This is the first observation of the effect of confinement in a very well-characterized sample. These measurements can only be achieved in microgravity. We continue to see extra noise in the heat capacity data. It is thought that this noise can be attributed to a variation in heat input to the calorimeter in the sensitive frequency band around 55.2 Hz. Because of this, it is probable that additional high resolution scans beyond what are scheduled in the pre-planned Flight Objectives (FO) will be needed to achieve 100 percent of our science. November 24, 1997 (Flight Day 6) Things are moving right along. Today was spent collecting more high resolution data. With things going so well, the majority of my time is spent monitoring commands as they are issued by the science team. When a command is sent, I have to verify on the ground system computers that the command made it to the experiment successfully. I also make printouts of display screens every hour and record data in a log book. All of this information will be used after the mission to assist the scientists with their studies. November 25, 1997 (Flight Day 7) CHeX has completed a total of 27 high resolution data scans and has also completed the first low-noise high-temperature scan through the lambda transition, stopping as far as 0.8 mK above the transition. At least thirteen more high resolution data scans and one more high temperature scan will be needed to achieve our science goal for this mission. Another one of my functions during the mission is to coordinate command windows for the science team. A command window is a space of time when commanding from the ground to the orbiter is possible. Because the commands are sent so far away, they are bounced through satellites before reaching the orbiter. We have a schedule that shows the availability of these satellites and must coordinate through the Payload Communications representative (PAYCOM) to ensure that our commands will make it to the experiment. When the science team would like to send a command, I contact PAYCOM on the voice loop and request a command window. When he gives us a go, the scientists issue their commands and I verify that they reach CHeX and that CHeX accepts the commands. Once we have finished commanding, I inform PAYCOM that we no longer require a command window and it can be released to another user. 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, Columbia's remote manipulator system or robot arm was removed. Following inspections of the forward reaction control system, workers are planning to replace three thrusters over the next two weeks. Orbiter maneuvering system functional tests are nearing completion. With checks of the main propulsion system regulator complete, workers will need to replace two leaky valves on the system. Technicians removed the old window No. 6 and replaced it with a new window. Checks of the flash evaporator system were completed. Replacement of floodlights No. 1 and No. 5, in the orbiter's payload bay, is in work and aft flight deck reconfiguration proceeds on schedule. Voltage tests on Columbia's fuel cells are complete and APU leak and functional checks concluded yesterday. Power reactant storage and distribution system checks are complete and a 72-hour decay check is in work. FIRST STATION ELEMENT TO BE SHIPPED TO RUSSIAN LAUNCH SITE
The International Space Station will complete a major milestone toward its first launch as the first station piece, a U.S.-funded and Russian-built control module, is shipped from a Moscow factory next week to its Russian Space Agency launch site in Baikonur, Kazahkstan. In advance of the shipment of the control module, formerly called the Functional Cargo Block and designated by the Russian acronym FGB, a rollout ceremony and press conference will be held at the Khrunichev State Research and Production Center in Moscow at 11 a.m. Moscow time on Saturday, Jan. 17. Highlights of the rollout ceremony will be broadcast, tape-delayed, on NASA Television at 3 p.m. EST Saturday, with a repeat airing at 6 p.m. EST. The actual shipping of the control module is scheduled to begin on Thursday, Jan. 22. The 20-ton module is targeted for a late June launch to begin the five-year, 45-flight orbital assembly of the new space station. It will be launched on a Russian Proton rocket from the Baikonur Cosmodrome in Kazahkstan. The control module was built by the Khrunichev factory, under contract to The Boeing Company, the prime contractor to NASA for the International Space Station. It will depart Khrunichev via a special rail car late next week to begin the 1,200-mile, five- day train journey to Baikonur, where it will begin five months of launch preparations and final testing. "When the control module arrives at Baikonur, all of the elements for our first two launches will be undergoing final launch processing," International Space Station program manager Randy Brinkley said. "The year of the International Space Station is 1998. This is something that all of us have looked forward to for a very long time. We have a lot of exciting and challenging activities ahead as we begin our assembly in orbit. The incredible efforts of a worldwide engineering and development team will be coming to fruition, and a new, unprecedented phase of space construction will begin." Shortly after the control module is launched from Russia, Endeavour will launch on Space Shuttle mission STS-88 from the Kennedy Space Center, FL, with the second piece of the station, a connecting module called Node-1, built by Boeing at NASA's Marshall Space Flight Center, Huntsville, AL. The node was shipped to Kennedy to begin a year of launch preparations and final testing in June 1997. Two mating adapters have since been shipped to Kennedy from California and are being attached to the node prior to its launch. Endeavour's crew will dock the control module to the node and perform three spacewalks to make final connections between the two components during the 11-day flight. The station will then await the launch of the Russian-built Service Module, a component that will become the early living quarters, targeted for December. The first crew of the new station is planned for launch on a mission in early 1999. The 20-ton control module will provide early power and propulsion for the station as well as the capability to remotely rendezvous and dock with the Service Module. Construction began on the control module at Khrunichev in December 1994.
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