NASA's Spitzer Space Telescope Will Soon Retire. What Will Take Its Place?

On January 30, NASA plans to shut down its , which has provided key observations of the universe for the past 16 years. Spitzer gave crucial infrared data to scientists, and they are now looking to other telescopes to fill the gaps. Spitzer observes light in the infrared portion of the spectrum, which is light at longer wavelengths than what our eyes see. In the near-infrared (wavelengths closest to visible light), dust becomes transparent, letting astronomers peek into star-forming regions of galaxies or study cooler stars. At slightly longer wavelengths, infrared light can be used to study planetary systems around other stars and the disks that form them. At the longest infrared wavelengths, astronomers study cool clouds of dust and gas, and even peer into the hearts of galaxies wrapped in dusty clouds. Launched in 2003, Spitzer’s mission had two phases. Initially Spitzer’s instruments, cooled with liquid helium to –459 degrees Fahrenheit (–273 degrees Celsius), observed light with wavelengths from 3 to 160 micrometers during its cold mission. In 2009, the telescope ran out of coolant, beginning its “warm” mission. Spitzer could no longer observe longer wavelengths but continued observing at short wavelengths: 3.6 and 4.5 micrometers. But Spitzer is not the only space telescope in operation today, and current and future telescopes do have infrared-sensing capabilities. Here’s what astronomers will have in their infrared toolbox once Spitzer has been shut down.