Spitzer's Cryostat

In general, Spitzer's science payload needs to be kept very cold to work properly. This is because it uses infrared detectors that are very sensitive to heat. If the instruments are not very cold, the heat from the instruments themselves will interfere with the study of the faint infrared radiation from objects in space. Spitzer's cryostat will keep the science instruments at temperatures as low as 1.4 degrees Kelvin for up to 5 years.

Spitzer's cryostat will keep the instruments cold by venting helium vapor from a liquid helium tank. The cryostat consists of the vacuum shell, inner and middle vapor cooled shields, helium tank, and the fluid management system. The tank holds about 360 liters of superfluid helium.

The telescope is attached to the top of the vapor-cooled cryostat. The telescope and cryostat shell are launched warm, and cool down to about 35 degrees Kelvin once in orbit. The cryostat vacuum shell must be sealed during ground operations and launch. Once the cryostat is cooled and in the vacuum of space, a cryostat door on the top of the shell is opened to allow light into the Multiple Instrument Chamber.

Spitzer's cryostat being assembled Ball Aerospace

Cryostat after assembly Ball Aerospace

The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center.