I. Satellite Motion
Satellite - smaller body revolving around a larger body
Why Doesn't the Moon
Resource produced by WGBH
Intro to Gravity - Flash showmethephysics.com
Illustration from Newton's
Principia
Natural Satellites ![]() ex) Moon, all 8 planets, comet
Artificial Satellites
- weather, spy, communications
See where
the earth's
Click this link and wait until
A. Satellite Motion
1. To send artificial satellite in circular orbit around earth it must first achieve a speed of 7900 m/s
If greater than 7900 m/s satellite has an elliptical orbit
If velocity is greater than 11 km/s then satellite leaves earth's orbit (called escape velocity)
2. Air resistance slows down satellites and eventually causes them to spiral back to earth.
Meteorite Peekskill, Ct. (NASA)
Winslow, Arizona Crater created when a 50-meter-wide (160-foot-wide)
iron-rich David Roddy, USGS.
B. Geosynchronous Orbits
1. When a satellite orbits in time with earth’s rotation it is called geosynchronous.
2. Time for
one revolution - 24 hrs
3. A satellite at distance of 6 earth radii from earth's center will orbit earth every 24 hrs.
4. Since both satellite and earth move together, it always remains directly above same spot above earth’s equator.
Meteorite Impact in Virginia
PHET Animation
Why does the moon have so many craters
The moon has very little erosion. "On Earth, impact craters are harder to recognize because of weathering and erosion of its surface. The Moon lacks water, an atmosphere, and tectonic activity, three forces that erode Earth's surface and erase all but the most recent impacts. Approximately 80% of Earth's surface is less than 200 million years old, while over 99% of the Moon's surface is more than 3 billion years old. Essentially, the Moon's surface has not been modified since early in its history, so most of its craters are still visible."
Learn more about Circular Motion at Georgia Public Broadcasting
©Tony Mangiacapre., - All Rights Reserved [Home] |
|