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

Revision as of 16:01, 20 August 2022

Revision as of 04:00, 17 November 2022

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A new software upload in September 2008 necessitated a brief shutdown of the NICMOS cooling system. Several attempts to restart the cooling system were unsuccessful due to issues with the cryogenic circulator. After waiting more than six weeks for parts of the instrument to warm up, and theorized ice particles to sublimate from the neon circulating loop, the cooler once again failed to restart. An Anomaly Review Board (ARB) was then convened by NASA. The ARB concluded that ice or other solid particle migrated from the dewar to the circulator during the September 2008 restart attempt and that the circulator may be damaged, and determined an alternative set of startup parameters. A successful restart at 13:30 EST on 16 December 2008 led to four days of cooler operations followed by another shutdown.<ref>{{cite web|url=http://www.stsci.edu/hst/nicmos/newsItems/Nicmosncs_status_01232009|title=NICMOS/NCS Status|date=January 23, 2009|publisher=[[Space Telescope Science Institute]]}}</ref> On 1 August 2009, the cooler was restarted again;<ref>{{cite web|title=Hubble Space Telescope Status Report|date=August 5, 2009|publisher=[[NASA]]|url=http://www.nasa.gov/mission_pages/hubble/servicing/SM4/news/HST_update_5Aug2009.html}}</ref> NICMOS was expected to resume operations in mid-February 2010<ref>{{cite web|title=NICMOS Late Breaking News Page|date=December 16, 2009|publisher=NASA|url=http://www.stsci.edu/hst/nicmos/localNews?display_type=all#NICMOS_NCS_status_12162009|archive-url=https://archive.today/20120805163354/http://www.stsci.edu/hst/nicmos/localNews?display_type=all%23NICMOS_NCS_status_12162009|url-status=dead|archive-date=August 5, 2012}}</ref> and operated through October 22, 2009, at which point a lock-up of Hubble's data handling system caused the telescope to shut down. The circulation flow rate to NICMOS was greatly reduced during this operating period confirming blockage in the circulation loop. Continued operation at reduced flow rates would limit NICMOS science so plans for purging and refilling the circulation system with clean neon gas were developed by NASA. The circulation loop is equipped with an extra neon tank and remotely operated solenoid valves for on-orbit purge-fill operations. As of 2013, these purge-fill operations have not yet been performed.{{update after|2014}}

[[Wide Field Camera 3|WFC3]], installed 2009, was designed to partly replace NICMOS.<ref name=aas>{{cite journaljreport|title=Status of the HST Wide Field Camera 3 |first1=J.W. |last1=MacKenty |first2= R.A. |last2=Kimble|date=January 2003|publisher=American Astronomical Society poster session |url=http://www.stsci.edu/hst/wfc3/documents/published/aas_jan2003_poster1.pdf |page=1}}</ref>

On June 18, 2010, it was announced NICMOS would not be available for science during the latest proposal Cycle 18. As of 2013, a decision as to whether the purge-fill operations will be performed and whether NICMOS will be available for science in the future has not been made.{{update after|2014}}