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Hubble Operations

The Hubble Space Telescope orbits far above the Earth. There is a good reason it flies so high. It lets astronomers get a very clear picture of what they want to see. To do this, the Hubble has to be above the Earth's atmosphere. Why? Have you ever looked at a straw sitting in a glass of water? Did you notice that it looked bent? The water changes the way your eyes see the straw. When scientists look at things through Earth's atmosphere, the same thing happens. So, Hubble orbits above the sky. There is a downside to having the Hubble so high. It keeps scientists from looking through the telescope with their own eyes. They use tools on the Hubble to see things in space.

The Hubble Space Telescope floats in orbit above the Earth.
Image above: The Hubble Space Telescope Floats in Orbit Above the Earth.

The Hubble has a lot of tools. Two important ones are cameras and spectrographs. Hubble's cameras do not use film. They collect light. Spectrographs break up starlight into a rainbow of colors. Astronomers study the colors. They learn something from each color. They can tell a star's temperature. They can find out how it moves. They can tell what it is made of and how old it is.

The Hubble also has mirrors. They are used to pull the light together and make it stronger. The main mirror is inside a long, hollow tube. This keeps light from the Sun, Earth, and Moon from shining on the mirror. There are solar panels on the telescope that collect sunlight. The light is changed into electricity. Radio antennas let people at Goddard Space Flight Center know what the Hubble is doing. People at Goddard send messages to the Hubble all day long. The messages have to be changed into a code. Hubble's computer can understand the code.

With far-off galaxies in the background, a dusty spiral galaxy takes center stage in this NASA Hubble Space Telescope image.
Image above: With Far-Off Galaxies in the Background, a Spiral Galaxy is Spotted by NASA's Hubble Space Telescope.
Think about trying to point a laser on a dime 200 miles away. Could you hold it still for hours or days? This is what Hubble's pointing control system does. The Hubble locks onto an object. If Hubble starts to move, equipment moves it back where it belongs.

Hubble gathers facts about things in space. Its computers turn the facts into long rows of numbers. The numbers travel as radio signals to a satellite. It sends them to Goddard. Then it goes to the Space Telescope Science Institute. The numbers are turned back into pictures and words.

The facts Hubble collects in one day would fill an encyclopedia! The reports are stored on computer disks. Astronomers all over can use the disks to learn more about space.