Following 16 years of service, NASA has finally retired its Spitzer Space Telescope. The orbiting observatory has been instrumental in furthering our understanding of the universe, using a high-sensitivity to infrared light to pull in a long-line of groundbreaking discoveries about asteroids, distant galaxies and the TRAPPIST-1 system of Earth-sized exoplanets.
Spitzer was launched into an Earth-trailing orbit in 2003, placing it well away from the infrared emissions of our own planet. As the most sensitive infrared telescope ever constructed at the time, this enabled Spitzer to observe its surroundings in new wavelengths of light, offering us an entirely new perspective on the universe.
This included the detection of infrared light emanating from blazing-hot “super-Earths,” spotting some of the most distant gas giants and planets we’re aware of, and piecing together gigantic panoramas of the Milky Way. Among its odder findings were observations that helped scientists assess the size of ’Oumuamua, which Spitzer actually couldn’t see at all. The interstellar object was simply too small for the telescope to detect, helping researchers place a limit on its physical size. The telescope also played a huge role in our detection and understanding of the TRAPPIST-1 system, which caused a lot of excitement in scientific circles for its Earth-like planets and potential to harbor life. Spitzer also spent time studying objects closer to home, observing comets and asteroids blazing across the solar system and even uncovered a previously unknown ring around Saturn. “Spitzer has taught us about entirely new aspects of the cosmos and taken us many steps further in understanding how the universe works, addressing questions about our origins, and whether or not are we alone,” says Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate in Washington. “This Great Observatory has also identified some important and new questions and tantalizing objects for further study, mapping a path for future investigations to follow.