In-Flight Performance of the OCO-2 Cryocooler

[摘要] The Orbiting Carbon Observatory-2 (OCO-2) will have completed its first year in space on July 2, 2015. The OCO-2 instrument incorporates three bore-sighted, high-resolution grating spectrometers, designed to measure the near-infrared absorption of reflected sunlight by carbon dioxide and molecular oxygen. The cryocooler system design is coupled with the instrument's thermal control design to maximize the instrument's performance. A single-stage NGAS pulse tube cryocooler provides refrigeration to three focal plane arrays to ∼120 K via a high conductance flexible thermal strap. A variable conductance heat pipe (VCHP) based heat rejection system (HRS) transports waste heat from the instrument located inside the spacecraft to the space-viewing radiators. The HRS provides tight temperature control of the optics to 267 K and maintains the cryocooler at 300 K. Soon after entering the A-Train on August 3, 2014, the optics and focal planes were cooled to their operating temperatures. This paper provides a general overview of the cryogenic system design and reviews the in-flight cryogenic performance during the Observatory's first year.

[发布机构] Jet Propulsion Laboratory, California Institute of Technology, Pasadena; CA; 91109, United States^1

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Cryocooler system;Grating spectrometers;Heat rejection systems;In-flight performance;Near-infrared absorption;Operating temperature;Pulse tube cryocoolers;Variable conductance heat pipes