'The little telescope that could' has retired. It changed how we see the universe
By Ashley Strickland
The Spitzer Space Telescope's greatest exoplanet discoveries of all time
By Elizabeth Howell
RIP Spitzer, the Coolest Heat Telescope in the Solar System
By Daniel Oberhaus
NASA's Spitzer Space Telescope is no more. Here's what's next for infrared astronomy.
By Meghan Bartels