Summary Sending people to the Moon is a huge task. Help comprehend the mission challenges with a scale model, and gravity assist modelling. Science content Earth/Space: Sun, Moon, Solar System, Universe (1, 4, 6) Earth/Space: Extreme Environments, Space Exploration (6) Activities in this lesson Earth and Moon's orbit to scale Gravity Assist Model Procedure Make a scale model of the Sun, Earth and Moon, to visualize how far away the Moon is. The Moon is moving, orbiting the Earth in one month. Gravity assist to model how after launch, mostly gravity sent Integrity on its trajectory, including back to Earth The Artemis Moon mission (Orion spacecraft called Integrity) used fuel to escape Earth’s gravity, then gravity of the Moon/Earth to swing by the Moon and back to Earth. (Free return trajectory, a figure 8.) With this trajectory, even if there is an engine failure the capsule ends up back at Earth. (Fly in ahead of the Moon’s orbit, the Moon slows it down and makes it curve back towards Earth. Flying in behind the Moon’s orbit would sling the capsule further out into space.) Integrity orbited Earth once to test safety equipment, before day 2 trans-lunar injection burn. Then 3 days to the Moon, getting slower and slower as Earth’s gravity pulled on it. Entered Moon’s gravity on day 5. Day 6 far side of the Moon. Day 10 splashdown. Model how gravity sent Integrity back to Earth: Can you adjust the speed of the spacecraft to swing back towards Earth? Can you give it a figure 8 trajectory? (Possible by slanting the plexi sheet.) Discussion Gravity assist was used for the Artemis mission. It is also used for other missions that send probes across the solar system (with no people onboard). Real gravity assist also uses the movement of a planet or moon it is flying by to speed up/slow down, depending on: the direction of motion of the planet compared to the probe Grades taught Gr 3 Gr 4
