On Thursday, NASA’s Spitzer space telescope signed off and went silent. But even during its final week of operation, the spacecraft was making one-of-a-kind observations.

The telescope, the size of a family sedan, follows Earth in its orbit around the sun, but trails 158 million miles behind. Lately, it has gazed out with its infrared eyes, taking sensitive measurements of fine cosmic dust that pervades the space between planets in the solar system. The resulting imagery will enable researchers to better understand our local celestial neighborhood, while informing models of worlds circling other stars and giving insight into the early universe.

Since it launched on Aug. 25, 2003, Spitzer has provided unique contributions to science. It gave us new views of distant galaxies, newborn stars and nearby exoplanets, as well as of asteroids, comets and other objects in our solar system. Its infrared cameras have observed the universe in a light imperceptible to human senses, providing otherwise unattainable visions of the sky.

“There is no field of investigation that has not been touched by Spitzer,” said Daniela Calzetti, an astronomer at the University of Massachusetts, Amherst, who has used the telescope to study galactic evolution.