Near Infrared Camera and Multi-Object Spectrometer: Difference between revisions

Revision as of 20:28, 17 May 2009

Revision as of 00:59, 18 May 2009

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NICMOS was installed on Hubble during its second servicing mission in [[1997]] along with the [[Space Telescope Imaging Spectrograph]], replacing two earlier instruments.

When conducting infrared measurements, it is necessary to keep the infrared detectors cooled to avoid having infrared interference from the instrument's own thermal emissions. NICMOS contains a cryogenic [[Dewar flask|dewar]], that cooled its detectors to ~ 61 kelvinsK, and optical filters to ~ 105 K, with a block of solid [[nitrogen]] ice. When NICMOS was installed in 1997, the [[dewar flask]] contained a 230 pound (104 kg) block of nitrogen ice. Due to a thermal short that arose on [[March 4]], [[1997]] during the instrument commissioning, the dewar ran out of nitrogen coolant sooner than expected in January, 1999. During Hubble Service Mission 3B in 2002, a [[cryocooler]] and external radiator were installed on the Hubble that now cools NICMOS through a cryogenic [[neon]] loop. NICMOS was returned to service soon after SM 3B.

A new software upload in Sept. 2008 necessitated a brief shutdown of the