Spitzer Space Telescope

The Spitzer Space Telescope was an infrared space telescope launched in 2003 and retired on 30 January 2020.

Mission duration:

Planned: 2.5 to 5+ years

Primary mission: 5 years, 8 months, 19 days

Elapsed: 16 years, 5 months, 23 days

The planned mission period was to be 2.5 years with a pre-launch expectation that the mission could extend to five or slightly more years until the onboard liquid helium supply was exhausted. This occurred on 15 May 2009. Without liquid helium to cool the telescope to the very low temperatures needed to operate, most of the instruments were no longer usable. However, the two shortest-wavelength modules of the IRAC camera continued to operate with the same sensitivity as before the cryogen was exhausted, and continued to be used into early 2020 in the Spitzer Warm Mission.

Spitzer ran out of liquid helium coolant on 15 May 2009, which stopped far-IR observations. Only the IRAC instrument remained in use, and only at the two shorter wavelength bands (3.6 µm and 4.5 µm). The telescope equilibrium temperature is now around 30 K.

Part of the telescope body is a cargo bay that can be opened to see its innards. Mainly the cryogenic tank, some instruments, and the mirror.


The Atlas V will put the Centaur into LDO with almost 100% fuel. From there you can boost it into a heliocentric orbit.


AG 2 opens the scope door.


More rockets in Atlas series:

• Atlas V 522