The Spitzer Space Telescope was launched on August 25th, 2003. It is a space observation telescope that orbits above the Earth's atmosphere and uses infrared technology. It is the fourth observatory that NASA launched as part of the Great Observatories program and the last one that was launched by NASA. The Spitzer is the most sensitive infrared observatory ever launched. It was named after Lyman Spitzer, a famous scientist, who wrote extensively about building satellites in the 1940's.
By the 1970's scientists were beginning to try to find a way to launch a satellite that could detect infrared rays above the atmosphere. In 1983, the Infrared Astronomical Satellite was launched, which showed that an infrared space observatory was possible. The Spitzer originally was meant to be launched from the Space Shuttle, like the other Great Observatories projects. Unfortunately, the Challenger Disaster caused NASA to have to remake their shuttles. The redesign took a few more years, but by 2003 it was ready and launched by the Delta II launch vehicle.
The Spitzer carries many instruments on board for measuring infrared rays. These instruments include an infrared camera that can see the infrared rays, an infrared spectrograph to analyze the infrared rays for information about different molecules in space and the imaging photometer, which can analyze infrared rays at the ends of the spectrum. All of these instruments use liquid helium to cool them. Scientists can take all of this information and turn it into a picture of what the satellite is seeing.
In 2004, the Spitzer found an object that was slightly glowing. The object, which now is thought to be the youngest star that was ever located, was found in an area called L1014 that was made up of gases and dust. In May 2007, the Spitzer was used to map the atmosphere of HD 189733 b, which is the first time that a planet outside our own solar system was ever mapped.