It’s been months since NASA’s Kepler Space Telescope, the exoplanet hunter, lost its ability to lock on to distant stars and find planets orbiting around them. But it looks like NASA’s found a replacement telescope—the Spitzer Space Telescope—to keep the exoplanet hunt going while we wait for the James Webb Space Telescope to launch.
The Spitzer is going on ten years old, and has gotten an upgrade that will let it study distant stars for signs of life-bearing planets. The engineers and scientists who built Spitzer did not have exoplanet hunting in mind for their telescope. Far from it. Sean Carey of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena said that when Spitzer launched in 2003, the idea of using it to study exoplanets was so crazy that no one even considered it.
Spitzer was the final mission in NASA’s Great Observatories Program, a program that comprised four space telescopes all designed to look at the Universe and detect different types of light. Hubble is the visible light telescope, the Compton Gamma-Ray Observatory looks at gamma-rays, and the Chandra X-Ray Observatory detects x-rays. Spitzer was designed to last up to two-and-a-half years, during which it would detect infrared radiation, a long wavelength of light that occurs primarily in the form of heat radiation.
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