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NASA NTRS2007

Development of a Cryogenic Thermal Distortion Measurement Facility for Testing the James Webb Space Telescope Instrument Support Integration Module 2-D Test Assemblies

The James Webb Space Telescope Instrument Support Integration Module (ISIM) is being designed and developed at the Goddard Space Flight Center. The ISM Thermal Distortion Testing (ITDT) program was started with the primary objective to validate the ISM mechanical design process. The ITDT effort seeks to establish confidence and demonstrate the ability to predict thermal distortion in composite structures at cryogenic temperatures using solid element models. This-program's goal is to better ensure that ISIM meets all the mechanical and structural requirements by using test results to verify or improve structural modeling techniques. The first step to accomplish the ITDT objectives was to design, and then construct solid element models of a series 2-D test assemblies that represent critical building blocks of the ISIM structure. Second, the actual test assemblies consisting of composite tubes and invar end fittings were fabricated and tested for thermal distortion. This paper presents the development of the GSFC Cryo Distortion Measurement Facility (CDMF) to meet the requirements of the ISIM 2-D test. assemblies, and other future ISIM testing needs. The CDMF provides efficient cooling with both a single, and two-stage cryo-cooler. Temperature uniformity of the test assemblies during thermal transients and at steady state is accomplished by using sapphire windows for all of the optical ports on the radiation shields and by using .thermal straps to cool the test assemblies. Numerical thermal models of the test assemblies were used to predict the temperature uniformity of the parts during cooldown and at steady state. Results of these models are compared to actual temperature data from the tests. Temperature sensors with a 0.25K precision were used to insure that test assembly gradients did not exceed 2K lateral, and 4K axially. The thermal distortions of two assemblies were measured during six thermal cycles from 320K to 35K using laser interferometers. The standard deviation for all of the distortion measurements is less than 0.5 microns, which falls within the ISIM requirement of 3 microns.

Miller, Franklin↗

NASA NTRS1991

Final cryogenic performance report for the NASA Cosmic Background Explorer (COBE)

The cryogenic operation of NASA's Cosmic Background Explorer (COBE) ended on September 21, 1990, with the depletion of the liquid helium cryogen. The COBE had successfully completed more than 10 months of dewar and instrument operation. We report on the cryogenic performance of the COBE dewar and of the two cryogenic instruments throughout the mission lifetime. We discuss the steady state dewar performance, and the dewar and instrument response to a variety of transient thermal phenomena, including external radiation (from the earth and the sun) and instrument power variation. We present the effectiveness of using approximate mass gauging techniques in determining the liquid helium content. Finally we discuss the dewar behavior during the depletion of the helium, and the expected thermal performance of the dewar cryogen tank and the cryogenic instruments as they approach final thermal equilibrium.

Volz, S. M.↗

NASA NTRS2018

The Aeolus Mission Concept, an Innovative Mission to Study the Winds and Climate of Mars

Aeolus is a mission to provide the first set of global, seasonal, and diurnal data to characterize winds and study the climate of Mars. Aeolus measures surface and atmospheric temperatures, aerosol abundances, and Doppler shifts in atmospheric spectral lines. The payload includes a system of four of a new type of miniaturized Spatial Heterodyne Spectrometer (SHS) paired to two orthogonal viewing telescopes that can measure CO2 (daytime absorption) and O2 (day and night emission) lines in the Martian atmosphere. The Thermal Limb Sounder (TLS) instrument measures atmospheric temperature profiles and aerosol (H2O ice clouds, dust) profiles, and the Surface Radiometric Sensor Package (SuRSeP) measures the total reflected solar radiance, and surface temperatures down to 140K. These combined spectral and thermal measurements will provide a new understanding of the global energy balance, dust transport processes, and climate cycles in the Martian atmosphere. The mission concept for Aeolus consists of a single sub-100 kg secondary spacecraft in a highly inclined orbit, allowing it to pass over all local times. Aeolus attains global coverage of the surface for a mission duration of one Martian year, to capture climate patterns during each Martian season. This paper gives an overview of the Aeolus payload, spacecraft, and the methodology used to mature the Aeolus mission concept.

Mauro, David↗

NASA NTRS1983

Advanced X-ray Astrophysics Facility thermal control

A conceptual active/passive thermal control system design is presented for the Advanced X-ray Astrophysics Facility (AXAF), where the design variables considered in system optimization were vehicle orientation for environmental extremes, thermal coating properties, and insulation materials. Because power and weight are at a premium, the design was limited to one power module, resulting in a thermal control limit of 441 W of regulated power. The present study has determined that all thermal control objectives for AXAF's instruments can be met by the design considered. The thermal resistance schematics employed in this conceptual study are presented, together with simulated performance characteristics.

Fritz, C. G.↗

NASA NTRS2000

CPL Applications on the EOS-TERRA Spacecraft

This presentation reviews the use of Capillary Pumped Loops on the EOS-TERRA spacecraft, It starts with a brief review of the status of CPL technology. On the TERRA spacecraft, CPL's will be used for thermal control of 3 instruments. The document reviews the ground testing, and states that life testing will continue to run for three year, even after the launch.The document has schematic diagrams of the EOS-AM spacecraft, the Advanced Spaceborne Thermal Emission and Reflection Radiometer - Thermal-Infrared Radiometer (ASTER-TIR) CPL configuration, the Advanced Spaceborne Thermal Emission and Reflection Radiometer - Short-Wave-Infrared Radiometer (ASTER-SWIR). The use of Measurements of Pollution In The Troposphere (MOPITTS) Capillary Pumped Heat Transport System (CPHTS) is reviewed, and the performance is summarized in several charts. The use of CPHTS in the ASTER-SWIR is reviewed. The loops in the ASTER-TIR module is also reviewed, and the problems with the second loop temperature control is discussed.

Ku, Jentung↗

NASA NTRS2014

Nanophase Carbonates on Mars: Implications for Carbonate Formation and Habitability

Despite having an atmosphere composed primarily of CO2 and evidence for abundant water in the past, carbonate minerals have only been discovered in small amounts in martian dust [1], in outcrops of very limited extent [2, 3], in soils in the Northern Plains (the landing site of the 2007 Phoenix Mars Scout Mission) [4] and may have recently been detected in aeolian material and drilled and powdered sedimentary rock in Gale Crater (the Mars Science Laboratory [MSL] landing site) [5]. Thermal analysis of martian soils by instruments on Phoenix and MSL has demonstrated a release of CO2 at temperatures as low as 250-300 degC, much lower than the traditional decomposition temperatures of calcium or magnesium carbonates. Thermal decomposition temperature can depend on a number of factors such as instrument pressure and ramp rate, and sample particle size [6]. However, if the CO2 released at low temperatures is from carbonates, small particle size is the only effect that could have such a large impact on decomposition temperature, implying the presence of extremely fine-grained (i.e., "nanophase" or clay-sized) carbonates. We hypothesize that this lower temperature release is the signature of small particle-sized (clay-sized) carbonates formed by the weathering of primary minerals in dust or soils through interactions with atmospheric water and carbon dioxide and that this process may persist under current martian conditions. Preliminary work has shown that clay-sized carbonate grains can decompose at much lower temperatures than previously thought. The first work took carbonate, decomposed it to CaO, then flowed CO2 over these samples held at temperatures >100 degC to reform carbonates. Thermal analysis confirmed that carbonates were indeed formed and transmission electron microsopy was used to determine crystal sized were on the order of 10 nm. The next step used minerals such as diopside and wollastonite that were sealed in a glass tube with a CO2 and H2O source. After reacting these materials for a number of hours, thermal analysis demonstrated the formations of carbonates that decomposed at temperatures as low as 500 degC [7]. Further work is underway to carry out the weathering process under more Mars-like conditions (low pressure and low temperature) to determine if the carbonate decomposition temperature can be shifted to even lower temperatures, consistent with what has been detected by thermal analysis instruments on Mars.

Archer, P. Douglas, Jr.↗

NASA NTRS1979

Feasibility of determining flat roof heat losses using aerial thermography

The utility of aerial thermography for determining rooftop heat losses was investigated experimentally using several completely instrumented test roofs with known thermal resistances. Actual rooftop heat losses were obtained both from in-situ instrumentation and aerial thermography obtained from overflights at an altitude of 305 m. In general, the remotely determined roof surface temperatures agreed very well with those obtained from ground measurements. The roof heat losses calculated using the remotely determined roof temperature agreed to within 17% of those calculated from 1/R delta T using ground measurements. However, this agreement may be fortuitous since the convective component of the heat loss is sensitive to small changes in roof temperature and to the average heat transfer coefficient used, whereas the radiative component is less sensitive. This, at this time, it is felt that an acceptable quantitative determination of roof heat losses using aerial thermography is only feasible when the convective term is accurately known or minimized. The sensitivity of the heat loss determination to environmental conditions was also evaluated. The analysis showed that the most reliable quantitative heat loss determinations can probably be obtained from aerial thermography taken under conditions of total cloud cover with low wind speeds and at low ambient temperatures.

Bowman, R. L.↗

NASA NTRS1981

Remote sensing: Present and future

Satellite remote sensing technology is overviewed with particular emphasis on the present and planned LANDSAT satellite systems. Satellite-borne instrumentation and their capabilities are discussed including multispectral scanners, return beam vidicons, the thermal inertia mapper, and STEREOSAT instrumentation.

Bloemer, H. H. L.↗

NASA NTRS2013

Model of Dust Thermal Emission of Comet 67p-Churyumov-Gerasimenko for the Rosetta-MIRO Instrument

The ESA's Rosetta spacecraft will arrive at comet 67P/Churyumov-Gerasimenko in 2014. The study of gas and dust emission is primary objective of several instruments on the Rosetta spacecraft, including the Microwave Instrument for the Rosetta Orbiter (MIRO). We developed a model of dust thermal emission to estimate the detectability of dust in the vicinity of the nucleus with MIRO. Our model computes the power received by the MIRO antenna in limb viewing as a function of the geometry of the observations and the physical properties of the grains. We show that detection in the millimeter and submillimeter channels can be achieved near perihelion.

millimeter-submillimeter↗

NASA NTRS2016

Thermal Testing and Model Correlation for Advanced Topographic Laser Altimeter Instrument (ATLAS)

The Advanced Topographic Laser Altimeter System (ATLAS) part of the Ice Cloud and Land Elevation Satellite 2 (ICESat-2) is an upcoming Earth Science mission focusing on the effects of climate change. The flight instrument passed all environmental testing at GSFC (Goddard Space Flight Center) and is now ready to be shipped to the spacecraft vendor for integration and testing. This topic covers the analysis leading up to the test setup for ATLAS thermal testing as well as model correlation to flight predictions. Test setup analysis section will include areas where ATLAS could not meet flight like conditions and what were the limitations. Model correlation section will walk through changes that had to be made to the thermal model in order to match test results. The correlated model will then be integrated with spacecraft model for on-orbit predictions.

Thermal↗

NASA NTRS1989

An update of commercial infrared sensing and imaging instruments

A classification of infrared sensing instruments by type and application, listing commercially available instruments, from single point thermal probes to on-line control sensors, to high speed, high resolution imaging systems is given. A review of performance specifications follows, along with a discussion of typical thermographic display approaches utilized by various imager manufacturers. An update report on new instruments, new display techniques and newly introduced features of existing instruments is given.

Kaplan, Herbert↗

NASA NTRS2006

High-Speed Laser Scanner Maps a Surface in Three Dimensions

A scanning optoelectronic instrument generates the digital equivalent of a threedimensional (X,Y,Z) map of a surface that spans an area with resolution on the order of 0.005 in. ( 0.125mm). Originally intended for characterizing surface flaws (e.g., pits) on space-shuttle thermal-insulation tiles, the instrument could just as well be used for similar purposes in other settings in which there are requirements to inspect the surfaces of many objects. While many commercial instruments can perform this surface-inspection function, the present instrument offers a unique combination of capabilities not available in commercial instruments. This instrument utilizes a laser triangulation method that has been described previously in NASA Tech Briefs in connection with simpler related instruments used for different purposes. The instrument includes a sensor head comprising a monochrome electronic camera and two lasers. The camera is a high-resolution

Lavelle, Joseph↗

NASA NTRS2000

The Plasmasphere as Seen by the IMAGE EUV Instrument

The IMAGE spacecraft includes the extreme ultraviolet (EUV) imager, which is designed to view He+ plasmaspheric ions in the inner magnetosphere. These images provide the first opportunity to view the global distribution of plasmaspheric ions and their response to solar wind induced convection and the ring current. In addition to the generalized pattern of convection long believed to develop in thermal plasma, the EUV instrument is observing other meso-scale patterns of plasma distribution never before observed or postulated using in situ measurements. This poster presentation will present the "first light" observations of the EUV instrument and their possible interpretations.

Gallagher, D. L.↗

NASA NTRS2004

Chapter 9: MEMS Applications in Spacecraft Thermal Control and Chapter 13: Handling and Contamination Control Considerations for Critical Space Applications

Thermal control systems (TCS) are an integral part of all spacecraft and instruments. To operate properly all spacecraft components must be maintained within a specified temperature band, which in some instances can be quite tight (less than 1 degree C). Traditionally this is accomplished by "passive" designs, but with modem spacecraft and instruments it is increasingly necessary to use active thermal control technologies. Microelectromechanical System (MEMS) can be useful in developing an active TCS, and may be especially useful for small spacecraft. As the MEMS knowledge matures, the applications of MEMS in spacecraft thermal control emerges as a viable technology for thermal engineers. Potential applications include specialized thermal control coatings, thermal switches, and specialized filters for instruments. Although MEMS technology demonstrates benefits, it also poses challenges for thermal en,oineers due to the lack of in-flight MEMS data. As a consequence, in order to design a MEMS thermal control device and receive the full advantage, it is important to understand the potential impact of the space environment on MEMS devices and the design/operational constraints imposed in their use. An entire chapter is devoted to handling and contamination controls for Micro Electro Mechanical Systems (MEMS) in space applications due to the importance of the topic area to final mission success. Handling and contamination control is discussed relative to the full life cycle from the very basic wafer level processing up through on orbit deployment. MEMS packaging will drive the need to tailor the Handling and Contamination Control Plan in order to assure adequacy of the overall program on a program by program basis. Plan elements are discussed at length to assist the user in preparing and implementing effective plans for both handling and contamination control to prevent deleterious effects.

Osiander, Robert↗

NASA NTRS2021

Planetary and Lunar Environment Thermal Toolbox Elements (PALETTE) Project Year One Results

This paper summarizes the technology development progress made during year one of the three-year JPL PALETTE project, which is funded by the NASA STMD Game Changing Development (GCD) Program. The project goal is to ensure that a full “palette” of flight-ready (high TRL) thermal “toolbox” elements is available so that engineers can create passive, ultra-isolative thermal designs for science instruments on a variety of carriers in lunar/planetary extreme environments. PALETTE is structured to meet the need via four design/build/test tasks and four analysis/study tasks. This paper focuses on Tasks 1-4, the four design/build/test tasks. Task 1 involves the development of nested thermally-switched enclosures featuring a reverse-operation DTE thermal switch (ROD-TSW) in series with a propylene miniaturized loop heat pipe (mini-LHP). Task 2 involves the development of a parabolic reflector radiator (PRR) for low latitude lunar sites. Task 3 involves the development of a low effective emissivity (e*) multilayer insulation (MLI) known as “spacerless” MLI. Finally, Task 4 involves the development of low conductance (G) thermal isolators. Available test results for all four tasks will be summarized in the paper, as will the plans for the remainder of the PALETTE project.

Britton, Shawn R↗

NASA NTRS2010

Thermal Design Considerations of the Hubble Space Telescope (HST) Science Instrument Control and Data Handler (SI C and DH-2)

Following a failure in side 1 of the HST SI C&DH in September 2008, HST Servicing Mission 4 (SM-4) was delayed so that a SI C&DH Orbital Replacement Unit (ORU) could be qualified for flight. This second generation SI C&DH (SI C&DH-2) included several enhancements which increased its thermal dissipation near critical components. In order to maintain the SI C&DH-2 within its operational temperature limits, several thermal modifications were installed prior to its final qualification testing. This paper presents the thermal modifications performed on the SI C&DH-2, as well as the thermal ground test results and a correlation of the SI C&DH-2 thermal design to flight telemetry.

Gregory, Teri H.↗

NASA NTRS1993

Topex Microwave Radiometer thermal control - Post-system-test modifications and on-orbit performance

The Topex Microwave Radiometer has had an excellent thermal performance since launch. The instrument, however, went through a hardware modification right before launch to correct for a thermal design inadequacy that was uncovered during the spacecraft thermal vacuum test. This paper reports on how the initially obscure problem was tracked down, and how the thermal models were revised, validated, and utilized to investigate the solution options and guide the hardware modification decisions. Details related to test data interpretation, analytical uncertainties, and model-prediction vs. test-data correlation, are documented. Instrument/spacecraft interface issues, where the problem originated and where in general pitfalls abound, are dealt with specifically. Finally, on-orbit thermal performance data are presented, which exhibit good agreement with flight predictions, and lessons learned are discussed.

Lin, Edward I.↗

NASA NTRS2005

Development of Particulates and Aerosols Research

During the past year several accomplishments were made for both the Particulate Matter Characterization and Measurement System, (PMCMS) and PAGEMS projects. The PAGEMS focus is to measure particulate emissions as a function of combustor parameters such as inlet temperature, inlet pressure and fuel air ratio. These measurements are used to evaluate combustor performance in hopes of correlating particulate emissions with engine conditions. These measurements have taken place at in-house NASA combustor facilities and off-site facilities. Ths work is unique because particulate measurements at high- pressure conditions are not commonly made. Some calibration of the PAGEMS instrumentation was done as well as minor modifications to the PAGEMS plumbing setup. These led to measurement improvements. The instrumentation and measurement process for PAGEMS was assessed and new instruments such as a thermodenuder, thermal mass flow meters and a cyclone separator were purchased to improve the PAGEMS instrumentation and measurement process. A worksheet was created to simulate varying inlet conditions to the DMA. This worksheet allows the user to assess the error in the measurements when certain conditions exist. Two technical papers were written with the PAGEMS team for the EXCAVATE field project. A paper was also reviewed for an in house publication. Also data was processed and analyzed for another field project (PAX) and will be part of a third PAGEMS paper. Accomplishments were also made with the PMCMS project. The calibration of the radial differential mobility analyzer, (RDMA) in the particle sizing system in the PMCMS was completed and provided satisfactory results. The voltages used for the RDMA depending on the particle of interest were corrected. The measurement capability of the PMCMS was increased by replacing the MetOne CPC with a TSI CPC. Lastly, assistance was provided to three college summer students with calibration of their particulate equipment and Monica Rivera shared her understanding of the aerosol technology with them. She also provided input for their end of the summer presentations. And attended the Aviation and Particle Emissions workshop. This workshop brought together experts in the aircraft particulate emissions field. As a result Ms. Rivera made two significant contacts with academia (UMR) and government (WPAFB) which could lead to future collaboration. She also attended the Aerosol and Particle Measurement Class held at the University of Minnesota. This class refreshed her particulate knowledge and introduced her to new aerosol applications and technology. Furthermore at the class contacts were made with private industry (TSI) and government (WPAFB). Ms. Rivera also enhanced her education by taking an in-house class on aircraft design and operation.

DeWitt, Kenneth↗