Spitzer Space Telescope: Innovations and Optimizations in the Extended Mission Era

Abstract

NASA's SpitzerSpaceOps Conferences 2 observational capabilities remain either undiminished or improved, and the high overall science data collection efficiency remains nearly unchanged. In this contribution, we outline several operational changes, innovations, and optimizations that have both minimized the impact of the growing distance on data transmission and enhanced the precision of data acquired by the science instruments.Though faced with diminishing budgetary resources that reduced staffing and allowed fewer upgrades of aging equipment, extended mission operations can provide an opportunity to acquire extensive science at bargain prices. The spacecraft, ground, and mission operations systems and procedures to perform the extended mission are already in place from the prime mission. The key to maintaining successful extended operations is the proper automation, modification and process enhancement of extant prime mission capabilities and procedures to maximize science return with acceptable risk as opposed to the creation of new capabilities. Spitzer's successful optimization of existing operational capabilities and the associated lessons learned that have gone into maximizing the lifetime well into its second decade of operation will hopefully provide guidelines for future missions, as it continues to make important contributions to the field of astrophysics, including the recent, highly significant discovery and characterization of exoplanets in the TRAPPIST-1 system.

On-orbit performance of the Spitzer Space Telescope: science meets engineering

“…These challenges, discussed in detail in Ref. 3, arose from several considerations. The first was the reduced data downlink rate-from 2.2 Mbps early in the mission to 0.55 Mbps at the end-which was a consequence of the increased distance of Spitzer from Earth.…”

“…8 Average number of pixels in the IRAC arrays affected by cosmic rays in the calibration frames taken during the Spitzer warm mission. 3 The array formats were 256 × 256 30-μm-squared pixels. The spike in 2012 was due to a solar flare.…”

On-orbit Performance of the Spitzer Space Telescope: Science Meets Engineering

“…These challenges, discussed in detail in Ref. 3 2 The dust cover atop the telescope tube was jettisoned a few days after launch, and the cryostat aperture door was opened shortly afterwards to admit infrared radiation into the instrument chamber. See papers listed in the appendix for a detailed discussion of the in-orbit checkout for Spitzer.…”

“…These images were also used to count the number of bad, noisy, and dead pixels. 3 The array formats were 256×256 30µm-squared pixels, The spike in 2012 was due to a solar flare.…”

“…The √ 2 photo-electron recombination penalty is included for all bands except IRAC 1 and 2, where it does not apply.Figure8. Average number of pixels in the IRAC arrays affected by cosmic rays in the calibration frames taken during the Spitzer Warm Mission 3. The array formats were 256×256 30µmsquared pixels, The spike in 2012 was due to a solar flare.Figure9.…”