Zero G Training - 1 of 7 Zero G Training
Brief Summary
Astronauts train for microgravity by flying in a specially equipped aircraft, the KC-135, nicknamed the “Vomit Comet.” This demonstration simulates a training flight in the Vomit Comet where visitors can witness a miniature “astronaut” experiencing weightlessness.
Equipment Required
“Zero G Training” media Soft sculpture canister cover Media controller (remote control) Catching sheet Vomit Comet model (canister Video recorder and with video camera in lid.) remote control Astronaut doll and helmet Demonstration Cart If possible, a partner
Main Teaching Points
Astronauts train for WEIGHTLESSNESS by flying PARABOLIC ARCS in the KC-135 Vomit Comet. This simulates weightlessness because the aircraft and its contents (the astronauts) are falling at the same rate. They are in a state of FREEFALL. In our demonstration, we can view simulated freefall on the video monitor because the camera inside the canister falls at the same rate as the miniature astronaut. We are viewing the experiment from the FRAME OF REFERENCE of the falling canister.
Educational Strategy
This demonstration is presented in the round, an arrangement that encourages an informal, conversational interaction between visitors and presenters. The basics of microgravity and freefall are introduced in a question and answer format, augmented by video sequences and animations which allows the presentation to respond to the visitors’ curiosity. In the “experiment” portion, several visitors are enlisted as helpers, and the experiment is done “street theater” style. This adds to the fun. By the use of video technology, the visitors are able to watch the experiment from two different points of view, or reference frames. This is a very important technique in science and a very important cognitive skill. Finally, since the Zero G Training - 2 of 7 “experiment” doesn’t work every time, the visitors get a feel that they are participating in an experiment rather than passively watching a slick demonstration.
Set Up
All experimental equipment ready to go on its own cart: Canister Camera lid (check battery) Astronaut doll and helmet Canister cover (soft-sculpture, shaped like a plane) Catching sheet Remote control unit Media on screen (playing the “Floating in Space” sequence) AV equipment (camera, recorder) checked and ready. Microphone on, lights adjusted
Suggested ways of presenting demo
This demo works very well when presented by two people working together.
Try this:
1. Gather your Audience Turn on “Floating in Space” sequence and invite visitors over by telling them that you are going to show actual weightlessness, exactly like the astronauts use to train for space travel. As your audience is building, engage them in questions like, “Who here would like to go into space?” “Who here would never like to go into space?” This begins to set up the conversational tone that you hope to keep during the entire presentation. 2. How do astronauts train for weightlessness? Return the media to the main screen entitled “Weightlessness” Ask: Does anyone here know how astronauts train for weightlessness before they go into space? Move to the “Training” screen. In response to their answers, show (or don’t show) the “Water Tank” video (a video about NASA’s Neutral Buoyancy Tank). If visitors bring up the Vomit Comet, say that that is correct, and that you want to show how that works. 3. How it works Go to the “How it Works” screen and show the “Elevator” video.(A video which shows how falling in an elevator is the same as being weightless (at least from the point of Zero G Training - 3 of 7 view of inside the elevator) than relates this to how the space shuttle is “falling” around the Earth.) Go back to the “Training/Vomit Comet” screen and show the “Trajectory” video, describing the different parts as they happen. 4. Getting ready for the experiment Show clear canister and model astronaut (no camera lid). This is a model of the Vomit Comet. Put astronaut doll into canister, toss into air and catch. Point out how astronaut “floats” inside the canister. Show video camera lid. Turn on camera and switch monitor to display live video feed. Have some fun pointing the camera at different things and letting visitors see the image on the screen. This is very important because the visitors must be clear in their minds that the image on the screen comes from the camera. Temporarily place the camera lid onto the canister to show how, in a moment, we will be able to watch the experiment from the “inside the vomit comet canister” point of view. Put canister and lid down on cart, pick up catching sheet. Select two volunteers from the audience. Show them how to hold the catching sheet. (Each holds two handles of the same color.) Their job is to catch the Vomit Comet. Practice tries. Without the camera lid attached, throw the empty Vomit Comet canister several times and have helpers catch it. Try some high throws, and some long throws. Here is another place to have fun. Make the catchers run a little if you’d like. 5. Doing the experiment: collecting data Put the astronaut and helmet into the canister and attach the video lid. Be sure the orientation of the lid is such that “up” is up. Explain that it usually takes a couple of tries to get a good throw, so ask the audience members to watch either the screen or the actual canister to see if it looks good. This request does several things. It takes the heat off of you to have “perfect” throws every time. It gives the visitors the idea of doing an experiment in that you often need to take lots of tries to get some good results. And, it brings the audience onto “your side.” That is, everyone is in it together trying to get good results rather than you (the presenter) trying to please and entertain them (the visitors). Start the video recorder. Do several tosses until the visitors think there was a “good” one. Cover the canister with the soft-sculpture canister cover. This is to block out information from the outside world. Do several more throws until you get another good one. Stop the recorder. Turn off the camera. Put the catching sheet away and thank your helpers. They are done. 6. Analyzing the videos Use the forward, backward, slow-motion, etc. controls to view the videos. It is especially cool to show things in slow motion. While watching one of the segments with the canister cover on, pause the recorder and ask, “Which way is up?” 7. Inside the Vomit Comet Reset the monitor so that it displays the Weightlessness media. Zero G Training - 4 of 7 Go to the Vomit Comet screen and show the “Ride” video. (Video of people inside the actual Vomit Comet.) 8. Other Stuff Depending upon the desires of the group, there are several other video clips you can look at. Or, you can try other experiments with the apparatus.
Operating Tips
Selecting volunteers from the audience: Choose people that you want to use, not necessarily the ones that raise their hands the highest. These volunteers will be catching the video equipment. While this is very easy to do, you still want people who can do it successfully. So, don’t feel obliged to use little kids if you don’t want to. It’s OK to use adults, even if there are kids in the audience. Make sure that the volunteer catchers stand far enough apart so that the sheet doesn’t drag on the floor.
Questions and Answers
Is this actual weightlessness or just a simulation? For the sake of this demonstration, I usually just say that this is how NASA simulates microgravity. That is easy for people to grasp. However, this is NOT just a simulation; there is actually a microgravity environment set up in the canister. In the General Theory of Relativity, Einstein claimed that if you were to close all of the windows and remove any visual clues from the outside, it would be impossible to tell if you are free-falling in a gravitational field or you were floating far off in interstellar space. And, according to him, if there is no physical way to tell the difference, then there is no difference. Everything really depends upon your point of view, or frame of reference. From the frame of reference of the ground, the astronaut is falling. From the frame of reference of the canister (or Vomit Comet) the astronaut is truly weightless. Both descriptions are equally correct. It is all relative. So, it is correct to say that this is a demonstration of actual weightlessness. Demo: Look at a video segment where the sleeve was on the canister. See if there are any clues that the astronaut is not weightless.
How long does a ride in the real Vomit Comet last? Each arc yields about 30 seconds of weightlessness. There are 40 arcs in a typical training session.
Is there any gravity up where the Space Shuttle flies? Yes. In fact, there is over 90% of the gravity that there is at Earth’s surface. Why, then, don’t things fall? The answer is that they do. The Space Shuttle (and everything in it) is falling towards the Earth. But, it is also traveling “forward” at about 17,000 mph. This is just the right speed so that in a unit of time, the Earth curves away below the Space Shuttle exactly the same amount as the Space Shuttle falls. The net result is that the Shuttle gets no closer to the Earth, but, rather, orbits the Earth. Demo: Show the “Orbits” video in the “How it Works” section of the media. Zero G Training - 5 of 7 Where does the name “Microgravity” come from? Hundreds of miles above Earth where spacecraft orbit, the atmosphere becomes very, very thin. Due to collisions with air molecules, the Space Shuttle is always slowing down slightly. For that reason, if you were to let an object float inside the Shuttle it would not stay where you put it. It would slowly move towards the front of the Shuttle (that is, the forward end in the direction of motion.) It is this slight drifting of items inside the Shuttle that inspired the term “microgravity.” This air pressure gives the equivalent of about one millionth of a “g.”
Why do they call it the Vomit Comet? Why do you think? Demo: Oh, that’s disgusting. Zero G Training - 6 of 7 Other Cool Stuff to Try
Put the astronaut doll on the sheet, toss him/her and ask what the view of us would look like from his or her frame of reference.
Fast Facts
The movie “Apollo 13” was filmed inside the Vomit Comet. A specially-designed set was created for the actors, and the “floating” portions of the movie were filmed in 30-second (or less) clips.
Potential Problems
Not catching the canister. People, including adults, tend to watch the TV monitor and take their eyes off the canister. Limp sheet problem. When people move to catch the canister, they can get too close together. Catching the canister doesn’t help much if the sheet is touching the floor. Rebound problem. If the sheet is too tight, the canister just bounces off and lands on the floor. Lack of performer fluency using the equipment and its hand held controller. Long empty pauses kill demos.
Background materials (websites, videos, articles, digital collections links)
http://www.grc.nasa.gov/WWW/PAO/html/microgex.htm NASA webpage What is Microgravity? http://spacelink.nasa.gov/Instructional.Materials/Curriculum.Support/Physical.Science/Mic rogravity/Microgravity/ Educator’s Guide to Microgravity from NASA Zero G Training - 7 of 7 Self assessment suggestions
After doing the ZERO G TRAINING demonstration several times, complete the checklist, then highlight the box in the rubric that best describes your performance. Have your team leader observe your demo then complete an identical rubric. Discuss your presentation technique with your team leader along the lines of the rubric.
Assessment for ZERO G TRAINING DEMO DATE______PRESENTER______
A. Checklist of pre-requisite skills 1. Can set up, operate & put away all props and media equipment 2. Can articulate in layman’s terms how freefall simulates weightlessness using the concept of frame of reference 3. Fully understands the idea of weightlessness as seen in 1) orbiting spacecraft, 2) Vomit Comet 3) the canister in our demo 4. Can incorporate the media clips seamlessly into your presentation 5. Knows the sequence of this demo a) Gather your audience b) Explain how astronauts train for weightlessness c) Explain how microgravity works d) Get ready to throw the canister e) Throw the canister and record on video f) Review the video
B. Rubric for ZERO G TRAINING QUALITY LEVELS OK EXCELLENT TRAITS
Knowledge of the science Can answer visitor questions Can go beyond visitor question correctly and add interesting facts gleaned from various resources Effectiveness using props Can make a smooth Can do the demo using presentation using each prop at several different approaches some time during the demo and can incorporate props in any order Educational strategy Presents a step-by-step Uses a step-by-step approach explanation, allowing visitor to and actively insures visitor is digest one concept before going ready to move on by asking onto another one. appropriate questions Fluency with media Can boot up and use all Can also use other media specified media bits without resources for enrichment delay Presentation style Can gather and engage a Presentation sparkles. crowd. Enthusiasm, humor, connection with crowd all make this an amusing and informative event.