Hubble Space Telescope |
How Many Space Telescopes Can You Name? Most people will immediately thing of The Hubble Space Telescope and all the amazing images that have been on TV and the Internet. Believe it or not, there are dozens of telescopes orbiting Earth right now, and dozens more whose mission has been terminated.
Telescopes are placed into orbit around the Earth or are sent farther out into space to get a clearer view of the Universe. There are many different types of space telescopes. Some are used to study a special object like the Sun. Others are used to study the different types of light given off by objects in space.
X-ray and gamma-ray telescopes study the hottest and most explosive objects in space. Infrared telescopes study the places where stars are born and can look into the centers of galaxies. Optical telescopes study the visible light from space and ultraviolet telescopes study very hot stars. Many of these types of light (such as x-rays, gamma-rays, most ultraviolet, and infrared) can only be studied from space because they are blocked by our atmosphere. Reference
NASA has four large powerful space-based telescopes called the Great Observatories. Their mission is to examine a particular region of space using differing technologies.
Spitzer Space Telescope |
The Hubble Space Telescope: launched in 1990 aboard Discovery, it observes visible and near-ultraviolet light.
The Compton Gamma Ray Observatory: launched in 1991 aboard Atlantis observes gamma rays. In 2000 it was deorbited due to a failed gyroscope.
The Chandra X-ray Observatory: launched in 1999 aboard Columbia observes soft x-rays.
The Spitzer Space Telescope: launched in 2003 aboard a Delta II rocket it observes the infrared spectrum.
Kepler Space Telescope |
The Hubble and Kepler (see my post about the Kepler Space Telescope HERE) are optical telescopes, which captures optical or visible light. There are no atmospheric effects in space, so the resolutions are significantly higher. This is why placing a space observatory on the moon makes so much sense.
Cameras images are monochrome, meaning one color. Different filters are used to capture infrared (deep red in color) or ultraviolet channels (deep blue in color). These images are then combined to make a single image. So those amazing images we see are not how the space telescopes capture them. Rather, they are combined to make a false color version. This method is used by astronomers to make the images more comprehensible.
Example: Here are actual images of the asteroid Ida taken by NASA’a Galileo satellite. On the right is a false color image. This reveals more of what elements make up the asteroid.
Here are a few more examples of false colored images:
Comet Halley |
I hope you enjoyed this post. We live in an incredibly amazing universe and with the use of space telescopes are beginning to unravel the secrets of our cosmos.
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