EXPLORE! A Cooperative Project of the Lunar and Planetary Institute, NASA's Office of Space Science and public libraries

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1 EXPLORE! A Cooperative Project of the Lunar and Planetary Institute, NASA's Office of Space Science and public libraries Activity: Space Capsules: The Egg-stronaut Egg Drop Level: Grades 5-8 To Take Home: Space Capsule Design Background Information Space Capsules To design and build a space capsule that will survive re-entry through the Earth's atmosphere (or that of another planet) and impact on the surface requires knowledge of the forces of gravity and acceleration along with test design trials. Many early spacecraft that orbited the Earth landed on land or water (which is still quite a hard surface if you are traveling at high speed!). The Mercury, Gemini and Apollo spacecraft all landed in the water with the aid of parachutes. The Russian Soyuz spacecraft landed (and still lands) on land with the aid of parachutes and jet firings. The Mars Pathfinder crashlanded on the surface of Mars in 1997 with the aid of parachutes and protected by airbags. The Hugyens probe to the surface of Saturn's moon Titan (carried on board the Cassini spacecraft) must be able to land safely on land or water because the surface is unknown due Titan's thick clouds. TYPES OF SPACE CAPSULES MANNED CAPSULES There have been many types of capsules developed by NASA. The Mercury capsule carried America's first astronaut, Alan Shepherd, into space and the other astronauts in the Mercury program. The Gemini capsule carried the second generation of astronauts into Earth orbit for longer stays and docking maneuvers. The Apollo capsule took astronauts to the Moon, and the Lunar Lander landed 12 astronauts on the surface. The Russian Soyuz capsule has launched and returned dozens of Russian cosmonauts from Earth orbit. Space capsules have not always been successful; one early Soyuz capsule lost three cosmonauts when it depressurized upon re-entry. The Apollo 1 capsule lost three

2 astronauts on the pad during a test when a fire broke out in its pure oxygen atmosphere and the hatch could not be opened fast enough for the astronauts to get out. The international space station will have permanently docked to it one and, later, two Soyuz escape capsules (each holds 3 persons) for emergency egress. It will also have a crew return vehicle built by NASA called the X-38, which will serve as an emergency vehicle for all seven space station crewmembers. The X-38 is remotely controlled and, after reentry, glides to a landing with the aid of parachutes and a parafoil. RUSSIAN SOYUZ X-38 CREW RETURN VEHICLE

3 UNMANNED CAPSULES Unmanned space probes have landed on Venus, the Moon, and Mars. The Russians sent eight Venera spacecraft to land on the surface of Venus beginning in The air pressure on Venus, extreme heat, and sulfuric acid atmosphere crushed and melted the probe within minutes. The last lander, Venera 14, survived for 57 minutes (the planned design life was 32 minutes) in an environment with a temperature of 465 C (869 F) and a pressure of 94 Earth atmospheres. Early U.S. and Russian Moon landers (the Surveyor and Luna programs, respectively) brought back images of the Moon before humans landed there. The Viking 1 and 2 Mars landers in 1976 sent back images and data from the martian surface. In 1997 the Mars Pathfinder bounced over the surface of Mars, landing right side up and opening to deliver the Sojourner rover to the surface to transmit images and data back to Earth. The Mars Polar Lander mission will torpedo two probes into the Mars polar cap, penetrating into the cap and then relaying data back to Earth. Future planned Mars missions include orbiters, rovers, and a sample return mission. LUNAR SURVEYOR MARS VIKING LANDER SOVIET VENERA MARS PATHFINDER

4 MARS POLAR LANDER HUYGENS TITAN PROBE All About Egg Drops Gravity and Momentum Gravity is the force that attracts bodies to one another. The Sun's gravity holds the planets in their orbits, and the planets' gravity hold their moons in orbit around them. Gravity pulls all objects down to the surface of a planet (and holds us down so we do not float away!). Spacecraft launched at high speeds against the pull of gravity orbit the Earth and then fire jets to re-enter the atmosphere. Gravity does the rest of the work bringing them home. G-force is a term used to express how many times the usual Earth gravity force an astronaut feels upon launch and upon re-entry when the speed creates the G-force. This is the feeling you have in a very fast roller coaster as you are being pushed back in your seat or in an amusement ride that spins and pins you against the wall. Early astronauts suffered from very high G-forces, making it hard to breathe or move. Today's shuttle astronauts experience only a few (2-3) G's upon launch and re-entry. The Russian cosmonauts, however, experience higher G's (6-7) upon launch and re-entry. As objects fall, they pick up momentum or accelerate until they impact the surface. Planets with atmospheres will create friction (and heat) with the spacecraft, which will slow re-entry down a small amount. Spacecraft like the shuttle are designed to fly like gliders and land aerodynamically. Space capsules like the Soyuz and early NASA Mercury, Gemini and Apollo capsules used parachutes to help slow their fall. Both types of spacecraft have heat shields on their bottoms. In the Egg-stronaut activity, gravity and momentum are the major forces acting on the space capsule.

5 Parachutes and Airbags Most space capsules use parachutes to help slow their descent, reduce their acceleration, and aid in a soft landing. The Soyuz spacecraft also fires jets immediately before impact to help reduce the force of the impact. The Mars Pathfinder used airbags in addition to parachutes and bounced along the surface before coming to rest. Both of these ideas make excellent additions to the egg-drop capsule and can be incorporated into students designs using string and plastic garbage bags for parachutes and inflated sandwich bags for airbags (freezer bags are even sturdier for high drops). Apollo Parachute X-38 Parafoil Mars Pathfinder Airbags Activity Timeframe - 90 minutes Egg-stronauts Materials Raw Eggs Hard-boiled eggs (or plastic eggs) Paper, Pencils, Markers Straws, Cardboard, Packing Material, Styrofoam, Meat Trays, Egg Cartons, String, Paper Towels, Garbage Bags, Cotton, Toothpicks, Dixie Cups, Sandwich Bags (other assorted materials) Scissors Cellophane Tape Drop Cloth Ladder (or balcony) Paper Towels

6 Introduction to Space Capsules You may choose to read a short story or chapter to the group about rockets to begin the session. It could be a story about Isaac Newton or Galileo and the force of gravity or an article about the early space program or the Mars Pathfinder mission. Share with the group some of the history of space capsules and the different types of capsules that have been launched by the United States and Russia. NASA handouts are included in this guide. You also can show a video about the history of the Mercury, Gemini, or the Apollo Missions or about unmanned missions like Viking or Pathfinder (see book and video lists). Timeframe minutes. Making Egg-stronauts Have the students carefully handle their raw eggs. Have them use markers to draw the face and body of their egg-stronauts on their eggs. Students can also name their eggstronauts. If you are concerned about students making a mess, you can have them wear smocks, not decorate their eggs, or use only hard-boiled eggs instead. Timeframe - 5 minutes. Designing Space Capsules Individually or in teams, students should plan out before hand on paper the type of capsule they will try to build. Have them look through the assembled items for construction before putting their designs on paper. Make sure they each do a drawing and label the parts and list the materials used. Timeframe - 10 minutes. Building Space Capsules Students should gather their materials and use hard-boiled or plastic eggs when making their test capsules. After they have built their test capsules according to design, you should allow them to make a test drop using the hard-boiled or plastic eggs. After the test drop, students can be given a chance to redesign their capsules. Drawings should be made of any changes to the design and choice of materials. When the final capsules are completed, students can retrieve their Egg-stronauts for placement inside the capsules. Students can design padded capsules, capsules with parachutes, capsules with airbags, or virtually any type of capsule using the materials on hand. Timeframe - 25 minutes. Egg Drop Contest Students will one at a time drop their capsules with their Egg-stronauts inside. One student can keep track of each launch by noting the name of the capsule, Egg-stronaut, and whether the Egg-stronaut survived. Timeframe - 20 minutes.

7 Procedure 1. Have the students draw a face and flight suit on their raw eggs using colored markers. They can name their Egg-stronauts at this time. Place raw eggs back in egg carton. 2. Have the students review all of the materials they can use for designing their space capsules. 3. Have them draw on paper designs for their space capsules. They can draw elevations, cutaways, or aerial views depending on their skill. 4. Have them label their drawings, name their capsules, and list their materials. 5. Have them build their test articles using hard-boiled (or plastic) eggs for their stand-in Egg-stronauts. 6. If time allows, have the students drop their test articles when they have completed construction. 7. If time allows, students can then redesign their capsules based on test results. Make sure they make changes to their drawings, noting the revisions in their designs. 8. Have all students drop their Egg-stronauts and space capsules as a group. This is the fun part! Have one student keep track of capsules, the Egg-stronaut names, and whether they emerged unscathed or not! Dropping your egg-stronauts safely Choose a balcony that is one or two stories high. Make sure students do not crowd around the drop zone. If using a tall ladder in an inside room, make sure that students are a safe distance back from the drop zone. Follow Up Questions Why was it important to design your capsule on paper first? Why was it important to build and test a test capsule? What variables were there in designing your capsule? (Types of materials, weight, and strength of material, etc.) What external factors may have affected the flight of your capsule? (i.e. wind) How does the size and weight of the capsule affect how fast it goes and how great the impact is? What would happen if your capsule were launched from a greater height? How you could improve the design of your capsule?

8 What might happen to these capsules on the Moon or Mars (where there is less gravity)? What might happen to these capsules on Venus (where there is more air pressure and higher temperatures)? Recommended Videos NASA (CORE) Catalog: To order by The Dream is Alive $30.00, Grades 4-adult, 37 minutes, 1985 The Flight of Apollo 11 (The Eagle Has Landed) $16.00, Grades7-12, 30 minutes, 1969 Pathfinder: The Race to Mars. NASA Briefings, 2-tape set,1998 Other Videos The Apollo Legacy. CNN. Apollo 13: For the Record. Jim Lovell Out of this World: The Apollo Moon Landings. Finley-Holiday, Inc. Inside the Soviet Union: the Space Race. Amazon.com Books you can borrow from your library Non-fiction Mercury Program Cole, Michael D. Friendship 7: First American in Orbit. Enslow Publishers, Inc. ISBN: Kallen, Stuart A. The Mercury Seven. Abdo & Daughters, ISBN: Sipiera, Paul P. and Sipiera, Diane M. Project Mercury (True Books). Children s Press, ISBN:

9 Gemini Program Kallen, Stuart A. The Gemini Spacewalkers. Abdo & Daughters, ISBN: X. Apollo Program Bean, Alan. My Life as an Astronaut Green, Jen; Bergin, Mark; and MacDonald, Fiona. Race to the Moon: The Story of Apollo 11 (Expedition). Franklin Watts, Cole, Michael D. Apollo 11: First Moon Landing. (Countdown to Space series). Enslow, Cole, Michael D. Apollo 13: Space Emergency (Countdown to Space series). Enslow, Fraser, Mary A. One Giant Leap. (An Owlet Book). Henry Holt. ISBN: Apollo-Soyuz Mission Tan, Sheri; Bond, Higgins; Rotunda, Matthew. Handshake in Space. Soundprints Corp. Audio, ISBN: Mars Pathfinder Mission Hamilton, John. The Pathfinder Mission to Mars. Abdo & Daughters, ISBM: Hawkes, Nigel and Rockwood, Richard. The New Book of Mars. Copper Beech Books, ISBN: Sumners, Carolyn T. and Handron, Kerry. An Earthling s Guide to Mars: Travel to Mars with Pathfinder. McGraw-Hill. ISBN: Space Travel Mullane, R. Mike. Do Your Ears Pop in Space?: And 500 Other Surprising Questions About Space Travel. Wiley and Sons, Science Experiments Vancleave, Janice Pratt. Janice Vancleave's Gravity (Spectacular Science Projects). John Wiley & Sons, ISBN:

10 White, Larry and Hamilton, Laurie. Gravity: Simple Experiments for Young Scientists. Millbrook Press, ISBN: Wiese, Jim. Cosmic Science: Over 40 Gravity-Defying, Earth-Orbiting, Space-Cruising Activities for Kids. John Wiley & Sons, ISBN: Fiction Harwood, Chuck. Bowled Over: The Case of the Gravity Goof-Up (Kinetic City Super Crew series). McGraw-Hill, ISBN: Verne, Jules. From the Earth to the Moon, and A Trip Around It. Related Internet Sites: NASA Home Page Mercury Program Gemini Program Lunar Surveyor Soviet Luna Program The Apollo Moon Missions Apollo-Soyuz Mission Soyez Spacecraft Russian Aerospace Guide Venera Spacecraft X-38 Crew Recovery Vehicle

11 Mars Pathfinder Mars Polar Lander Cassini Mission, Huygens Probe to Titan

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