Escape Velocity: Leaving a World
Students learn what escape velocity is, how it differs from orbital speed, and why it depends on a world's mass and size, from the Moon and Mars to Jupiter, the Sun and a black hole where nothing escapes.
Grades 5-8About 15 minutes of narrated flight, plus discussion stops8 stops
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What students will see and do
Students fly from Earth to the International Space Station, the Moon, Mars, Jupiter, the Voyager 1 spacecraft, the Sun and Sagittarius A* at the center of the Milky Way. Aetherion pauses for discussion at the ISS (how an orbit is endless falling), Mars (how a planet's size affects keeping its air) and Sagittarius A* (how scientists study something that gives off no light).
Learning objectives
- Explain escape velocity as the speed needed to break free of a world's gravity without further push.
- Compare orbital speed and escape velocity using the ISS and Earth as examples.
- Describe how a world's mass and size affect its escape velocity, using the Moon, Mars, Earth and Jupiter.
- Identify why nothing, not even light, can escape from inside a black hole's event horizon.
NGSS connections
| MS-PS2-4 | Students use evidence that gravitational force depends on mass, comparing escape velocities of small and large worlds. |
|---|---|
| MS-ESS1-2 | Students see gravity's role in orbits around Earth and the Sun and in the motion of stars around the galaxy's central black hole. |
| MS-ESS1-3 | Students compare scale properties (mass, size, surface gravity) of the Moon, Mars, Earth, Jupiter and the Sun. |
Stops on this journey
- The Ultimate Throw
- Orbit Versus Escape (discussion stop)
- An Easy World to Leave
- A Middle-Sized World (discussion stop)
- The Giant's Grip
- Escaping the Sun
- Escaping a Star
- Where Nothing Escapes (discussion stop)
Vocabulary
- gravity
- escape velocity
- orbit
- free fall
- gravity assist
- solar wind
- black hole
- event horizon