Engineering topics

Houck, James

Publications and source records attributed to Houck, James.

4 records

NASA NTRS2020

The Infrared Spectrograph on the Spitzer Space Telescope

The Infrared Spectrograph (IRS) instrument on the Spitzer Space Telescope covered the 5 to 38 micron wavelength range at low and medium spectral resolutions. The instrument was very popular during Spitzer’s 5.7 year-long cold mission. Every year it attracted the most proposals, and garnered more observing hours, of any of the science instruments. This success was the culmination of a very long development period, where the instrument design changed radically. When the instrument was first selected by NASA in 1984 it was very complicated. As part of the overall reduction of the size of the SIRTF Observatory following its recovery from the mission’s cancellation in 1991 the IRS became smaller and much, much simpler. The only aspect of the instrument that increased from the original design was the pixel count of the detectors. The new, lean, IRS based on eight axioms: (1) SIRTF is a cost-driven mission; (2) Only Boeing Si:As and Si:Sb 128x128 BIB arrays shall be used; (3) The IRS has all Aluminum housing and optics; (4) Simple optics consisting of surfaces of revolution, flat gratings, and “bolt-and-go” tolerances; (5) No moving parts; (6) Redundancy only for credible single-point failures; (7) Strive for an observing efficiency of 80%; (8) The IRS shall be capable of internal health assessment. This led to a simple, robust, but still extremely powerful final instrument composed of four distinct modules. Many of the features developed for the IRS were subsequently employed in other spacecraft and SOFIA science instrumentation. This presentation will cover the developmental history of the IRS instrument, its final design and performance, and will especially highlight the sage decisions that Jim Houck made along the way that led to its highly successful career on the Spitzer Space Telescope.

Roellig, Thomas L.↗

NASA NTRS2004

On-Orbit Performance of the Spitzer Space Telescope

The Spitzer Space Telescope (formally known as SIRTF) was successfully launched on August 25, 2003, and has completed its initial in-orbit checkout and science validation and calibration period. The measured performance of the observatory has met or exceeded all of its high-level requirements, it has entered normal operations, and is beginning to return high-quality science data. A superfluid-helium cooled 85 cm diameter telescope provides extremely low infrared backgrounds and feeds three science instruments covering wavelengths ranging from 3.2 to 180 microns. The telescope optical quality is excellent, providing diffraction-limited performance down to wavelengths below 6.5 microns. Based on the first helium mass and boil-off rate measurements, a cryogenic lifetime in excess of 5 years is expected. This presentation will provide a summary of the overall performance of the observatory, with an emphasis on those performance parameters that have the greatest impact on its ultimate science return.

Roellig, Thomas↗

NASA NTRS1991

Working Papers: Astronomy and Astrophysics Panel Reports

The papers of the panels appointed by the Astronomy and Astrophysics survey Committee are compiled. These papers were advisory to the survey committee and represent the opinions of the members of each panel in the context of their individual charges. The following subject areas are covered: radio astronomy, infrared astronomy, optical/IR from ground, UV-optical from space, interferometry, high energy from space, particle astrophysics, theory and laboratory astrophysics, solar astronomy, planetary astronomy, computing and data processing, policy opportunities, benefits to the nation from astronomy and astrophysics, status of the profession, and science opportunities.

Bahcall, John N.↗

NASA NTRS1991

Infrared astronomy

The decade of 1990's presents an opportunity to address fundamental astrophysical issues through observations at IR wavelengths made possible by technological and scientific advances during the last decade. The major elements of recommended program are: the Space Infrared Telescope Facility (SIRTF), the Stratospheric Observatory For Infrared Astronomy (SOFIA) and the IR Optimized 8-m Telescope (IRO), a detector and instrumentation program, the SubMilliMeter Mission (SMMM), the 2 Microns All Sky Survey (2MASS), a sound infrastructure, and technology development programs. Also presented are: perspective, science opportunities, technical overview, project recommendations, future directions, and infrastructure.

Gillett, Frederick↗