Systems Engineering Seminar

An Advanced Cryogenic Cooling System for the Hubble Space Telescope

Presented by:
Dr. Darrell Zimbelman/533

May 7, 2002, 1:00 p.m.
Building 8 Auditorium

Abstract:
The Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) instrument was installed into the Hubble Space Telescope (HST) in 1997 during the 2nd Servicing Mission. Following installation, an unexpected heat load was identified that reduced the instrument lifetime from 60 months to an actual operation of 22 months. In an effort to revive the on-orbit NICMOS instrument and restore the telescope's infrared scientific capability, an advanced cryogenic cooling system was installed during the recent HST Servicing Mission 3B. The NICMOS Cooling System (NCS) hardware consists of the NICMOS Cryogenic Cooler (NCC), an Electronics Support Module (ESM), a Capillary Pumped Loop (CPL)/Radiator, and the associated interface harnessing. The NCC is a state-of-the-art reverse Turbo-Brayton cycle mechanical cooler employing micro turbo machinery, driven by advanced power conversion electronics, operating at speeds up to 450,000 revolutions per minute to remove heat from the NICMOS instrument. The ESM provides command, control, and power distribution to the NCS, as well as providing the primary interface to the existing HST electronics. A two-phase CPL system removes heat from the NCC and transfers it to the radiator mounted externally on the HST aft shroud. This presentation provides an overview of the NCS followed by a discussion of the technical challenges and systems engineering issues overcome during the development and test activities.

Biography:

Dr. Darrell Zimbelman holds a Ph. D in Aerospace Engineering from the University of Colorado in the field of Guidance and Control, as well as an MS and BS in Aerospace Engineering also from the University of Colorado. He is currently a Senior Systems Engineer supporting the Hubble Space Telescope (HST) Project where he supported the technical development of the NICMOS Cooling System. Prior to working on HST, he led the development of the TRACE attitude control system and supported several spacecraft conceptual design studies. Before joining NASA Goddard in 1994, he worked as a GN&C engineer for both ITHACO, Inc. and Fairchild Space and Defense Corporation.