A Roundabout Way to Mars

Overview

Students explore orbit transfers and, specifically, Hohmann transfers. They investigate the orbits of Earth and Mars by using cardboard and string. Students learn about the planets' orbits around the sun, and about a transfer orbit from one planet to the other. After the activity, students will know exactly what is meant by a delta-v maneuver!

Engineering Connection

Aerospace engineers must be creative when planning the best routes and methods to send a spacecraft from Earth to another planet since space travel is never a direct linear path, but involves transfers between circular orbits. Engineers apply their understanding of math, especially geometry, to determine the most efficient interplanetary trajectories, and thus minimize costs by reducing the need for supplies and fuel as much as possible. They design techniques that take advantage of gravity and the behavior of forces in space.

NGSS Alignment

This lesson helps students prepare for these Next Generation Science Standards Performance Expectations:

• MS-ESS1-2. Develop and use a model to describe the role of gravity in the motions within galaxies and the solar system.

This lesson focuses on these aspects of NGSS Three Dimensional Learning:

Science & Engineering Practices	Disciplinary Core Ideas	Crosscutting Concepts
Developing and Using Models. Develop and use a model to describe phenomena.	ESS1.A: The Universe and Its Stars. Earth and its solar system are part of the Milky Way galaxy, which is one of many galaxies in the universe. ESS1.B: Earth and the Solar System. The solar system consists of the sun and a collection of objects, including planets, their moons, and asteroids that are held in orbit around the sun by its gravitational pull on them. The solar system appears to have formed from a disk of dust and gas, drawn together by gravity.	Systems and System Models. Models can be used to represent systems and their interactions. Scientific Knowledge Assumes an Order and Consistency in Natural Systems. Science assumes that objects and events in natural systems occur in consistent patterns that are understandable through measurement and observation.