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Astronaut Program
Communications
Launch
Deorbit and Landing
Living in Space
Mission Control Center
Sightings
Spacewalk
Any adult man or woman in excellent physical condition who meets the basic qualifications can be selected to enter astronaut training. For mission specialists and pilot astronauts, the minimum requirements include a bachelor's degree in engineering, science or mathematics from an accredited institution. Three years of related experience must follow the degree, and an advanced degree is desirable. Pilot astronauts must have at least 1,000 hours of experience in jet aircraft, and they need better vision than mission specialists. Competition is extremely keen, with an average of over 4,000 applicants for about 20 openings every 2 years. Astronaut recruiting occurs periodically.
For robotic arm training, the astronauts use several different simulators, with each possessing its own strengths. The Shuttle Engineering Simulator (SES) and the Shuttle Mission Simulator (SMS) are two computer simulators that are used extensively. Each one has actual switches and hand controllers to maneuver a computer model of the arm and the payload. Another heavily used simulator is the Mission Development Facility (MDF). This simulator utilizes real hardware, which includes a hydraulic robot arm, payload mock-ups, and cameras. To assist EVA operations, the NASA Neutral Bouyancy Labortory (NBL) has an underwater robotic arm. This is used to train the crew in joint EVA and arm operations.
Communications
STS-79 was the first operational flight of the Orbiter Communications Adapter (OCA). OCA allows Mission Control to link up with one of the crew’s laptop computers using the shuttle’s communication system. This connection is established at least once daily and allows both the uplink and downlink of data files. OCA is especially useful in providing scientists on the ground with near real-time insight into the status of onboard experiments. It also provides access to the electronic photographs taken by the crew which can be viewed on the JSC website. Internet access is not planned due to the need to protect onboard systems and data.
Yes, sometimes it is hard to understand what the crew is saying. We try to pronounce our words very carefully, and for critical calls, we even spell out words letter by letter to be sure. It helps to have practiced a lot, and to know what they're likely to call about. If all else fails, we just ask them to say it again!
Launch
At Main Engine Cutoff (MECO), the shuttle is at an altitude of approximately 70 miles, traveling 24927 ft/sec (about 17,000 mi/hr) relative to the earth. At that point, the Shuttle is still not yet "in orbit". If we did nothing else, it would come back to earth somewhere in the South Pacific ocean. In fact, the External Tank does fall there. In order to achieve a safe orbit, the Shuttle must coast to the highest point in its trajectory (somewhere over Europe) and add another 90 ft/sec with its Orbit Maneuvering Engines in order to raise the low end of the orbit to a minimum altitude.
Sound moves out and away from you in a circle, like a ripple in a pond from a stone, at a rate of about 700 mph. So if you fly 700 mph, all the noise you make builds up as a wave that moves along with you. During launch, we are going straight up, so that wave is travelling with us up. By the time we turn to parallel the Earth's surface, we're so high that there's no air to carry the sound. If you were in an a balloon at about 20,000 feet at the Cape, you would hear the Boom as the Shuttle climbed by. But the folks on the ground are all behind the Shuttle, so they never hear it.
Deorbit and Landing
The shuttle orbiter is a very "hot" airplane at landing. Typical landing speed for a commercial aircraft seldom exceeds 100 mph, even military fighter aircraft rarely touchdown faster than 130 mph or so. The shuttle orbiter target landing speed is 235 mph for main landing gear touchdown. And remember, there is only one chance to get it right!
The plasma field around the Shuttle is very visible through the windows as we fall into the atmosphere. It starts as flashes of light, and steadies out to an orange-red glow. It’s caused by the reaction of the high-energy vehicle (5 miles/second) ripping electrons from the rarefied gasses in the upper atmosphere.
Living in Space
Astronauts brush their teeth just like they do on Earth. There is no shower on the Shuttle, so astronauts must make do with sponge baths until they return home. Each Space Shuttle has a toilet that can be used by both men and women. Designed to be as much as possible like those on Earth, the units use flowing air instead of water to move waste through the system. Solid wastes are compressed and stored onboard, and then removed after landing. Wastewater is vented to space, although future systems may recycle it. The air is filtered to remove odor and bacteria and then returned to the cabin.
The humidity here is at about 20 percent onboard the shuttle, so we do notice that things dry out rather quickly, including us, and we try to drink more water than we normally do on the ground.
During a single-shift flight, we all sleep at the same time. We have a group of people in Mission Control who watch over us, and they have ways of waking us up. They can set off an alarm up here in the shuttle that will certainly get us out of the rack and get us looking at what they want us to look at. So we do all sleep at the same time but we're being watched over very carefully.
Mission Control Center
There are about 50 people on a team, three teams working about 9 hour shifts. In addition, there are many engineering people who support the mission in case there is a peculiar problem. Each team has a flight director and Capcom.
Yes we do allow food and drinks inside the Mission Control Center. Depending upon what is happening during the mission, most flight controller's shifts average between 8 and 12 hours with only 5- to 10-minute breaks every 90 minutes. So you can see that without food and drinks, there would be a lot of rumbling stomachs in the Control Center. One of our longstanding traditions in the MCC is the Food List. This is where each Flight Controller takes a day and delights his colleagues with cuisine of his own choosing. This way he only cooks (or buys) once and is covered for the rest of the mission
Sightings
If you live anywhere between 57 degrees above and 57 degrees below below the equator, you may be able to see the space shuttle in orbit at some time. During missions, the Flight Dynamics officers in Mission Control maintain a Sightings List. The orbiter is visible in the night sky when the vehicle itself is in daylight, so the hours before dawn and after dusk are the best times to see it.
Spacewalk
The space suit, called the Extravehicular Mobility Unit or EMU, uses 100 percent oxygen instead of air. When a crewmember does a spacewalk, the suit is pressurized to about 1/3 of atmospheric pressure. The amount of oxygen contained in air at this pressure is not adequate requiring the use of pure oxygen. Each EMU has two tanks (similar to scuba diving tanks) that hold enough oxygen to support a 9 to 10 hour spacewalk. The amount of oxygen consumed by a crewmember is dependent on his/her metabolic rate.
The EMU (Extravehicular Mobility Unit) has a drink bag which velcros to the front interior of the suit. The bag comes in two different sizes 21 oz and 32 oz and it is crew choice as to which bag they fly. The bag has a drink tube with a valve which prevents free flow of water into the suit. The valve is opened when the crew sucks on the tube for water. Their food is provided by a fruit bar wraped in an edible rice paper. The stick is stowed in a sleeve which is mounted to the neck area of the EMU. To eat the crew bend their neck down and take a bite of the bar and slide it up, which sets up for their next bite.
The primary requirement that any spacesuit must meet is to provide a pressurized volume for its crewmember. Lots of spacesuit improvements have been investigated and implemented over the years, but many of the more obvious shortcomings are probably here to stay. While the existing design is indeed bulky, it is a reliable, proven design that accommodates a wide range of sizes of EVA crew. There have been lots of new designs investigated, but all of them are equally bulky. It is simply not possible to decrease the bulk and provide improved flexibility without REALLY increasing the cost of each suit. Improvements such as better gloves, thermal comfort enhancements, and better helmet lights continue to be implemented as they are developed and made available.
