What Is a Satellite?
A satellite is an object that moves around a larger object. NASA has more than a dozen Earth science satellites in orbit. They help NASA study the oceans, land and atmosphere. These man-made machines are launched into space and orbit Earth or another body in space. There are thousands of man-made satellites. Some take pictures of our planet. Some take pictures of other planets, the sun and other objects. These pictures help scientists learn about Earth, the solar system and the universe. Other satellites send TV signals and phone calls around the world.
Why Are Satellites Important?
Satellites fly high in the sky, so they can see large areas of Earth at one time. Satellites also have a clear view of space. That's because they fly above Earth's clouds and air. Before satellites, TV signals didn't go very far. TV signals only travel in straight lines. So they would go off into space instead of following Earth's curve. Sometimes they would be blocked by mountains or tall buildings. Phone calls to faraway places were also a problem. It costs a lot and it is hard to set up telephone wires over long distances or underwater. With satellites, TV signals and phone calls can be sent up to a satellite. The satellite can then send them back down to different spots on Earth.
Landsat 8
On Monday, February 10th, NASA launched Landsat 8 into orbit from Vandenberg Air Force Base in California. This new satellite will spend a minimum of five years taking millions of pictures of Earth. Landsat 8 will cover the entire planet once every 16 days. Its main mission is to provide a detailed record of how Earth changes over time, such as the amount of urban growth or deforestation.
One of our classmates was lucky enough to witness the launch from the EROS data center outside of Sioux Falls. Below are some of the great pictures and videos he brought back to share!
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| Enjoying some of the exhibits at EROS |
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| A 3K student captures the launch of Landsat 8 from his front row seat at EROS data center outside of Sioux Falls |
Video taken by 3K student
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| Landsat 8 is already orbiting space and sending back pictures |
