This telescope is our next great detective in the universe

(CNN)After more than 16 years of observations, NASA's Spitzer Space Telescope came to an end on Thursday. It leaves a legacy of discoveries in its wake, which in turn has created new questions and intriguing targets for follow-up observations.

Spitzer was our infrared detective, spying exoplanets and distant galaxies. Now, there's a gap in infrared observations until NASA's James Webb Space Telescope launches in 2021. This large infrared telescope will be the premier observatory of the next decade, according to NASA.