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Technical Paper

Performance Characterization and Model Verification of a Loop Heat Pipe

2000-07-10
2000-01-2317
A simple Loop Heat Pipe (LHP) with a single evaporator and condenser was tested and modeled with two different working fluids: ammonia and propylene. While ammonia exhibits many desirable heat transfer characteristics, its freezing point is too high to prevent freezing in the condenser lines during a safing mode on a satellite platform. Consequently, propylene makes a good compromise since it has a lower freezing point and relatively good heat transfer properties. The performance of the LHP with ammonia was characterized by a series of tests with heat loads of 20 to 800 watts placed on the evaporator. With the LHP filled with propylene, it was tested with heat loads of 20 to 200 watts to the evaporator. The sink temperatures on the condenser ranged from −10°C to 20°C. The constant conductance performance of the LHP was 170 W/K with ammonia and 44 W/K with propylene. Steady state performance data of the LHP was used to validate a nodal network model of the device.
Journal Article

On-Orbit Thermal Performance of the TES Instrument-Three Years in Space

2008-06-29
2008-01-2118
The Tropospheric Emission Spectrometer (TES), launched on NASA's Earth Observing System Aura spacecraft on July 15, 2004 has successfully completed over three years in space and has captured a number of important lessons. The instrument primary science objective is the investigation and quantification of global climate change. TES measures the three-dimensional distribution of ozone and its precursors in the lower atmosphere on a global scale. It is an infrared (IR) high resolution, imaging Fourier Transform Spectrometer (FTS) with a 3.3 to 15.4 μm spectral coverage required for space-based measurements to profile essentially all infrared-active molecules present in the Earth's lower atmosphere. The nominal on-orbit mission lifetime is 5 years. The Aura spacecraft flies in a sun-synchronous near-circular polar orbit with 1:38 pm ascending node.
Technical Paper

On-Orbit Performance of the TES Loop Heat Pipe Heat Rejection System

2008-06-29
2008-01-2000
Launched on NASA's Aura spacecraft on July 15, 2004, JPL's Tropospheric Emission Spectrometer (TES) has been operating successfully for over three years in space. TES is an infrared high resolution, imaging fourier transform spectrometer with spectral coverage of 3.3 to 15.4 μm to measure and profile essentially all infrared-active molecules present in the Earth's lower atmosphere. It measures the three-dimensional distribution of ozone and its precursors in the lower atmosphere on a global scale. The Aura spacecraft was successfully placed in a sun-synchronous near-circular polar orbit with a mean altitude of 705 km and 98.9 minute orbit period. The observatory is designed for a nominal 5 year mission lifetime. The instrument thermal design features include four temperature zones needed for efficient cryogenic staging to provide cooling at 65 K, 180 K, 230 K and 300 K.
Technical Paper

Thermal Vacuum Testing of the Orbiting Carbon Observatory Instrument

2008-06-29
2008-01-2036
The Orbiting Carbon Observatory (OCO) instrument is scheduled for launch onboard an Orbital Sciences Corporation LEOStar-2 architecture spacecraft in December 2008. The instrument will collect data to identify CO2 sources and sinks and quantify their seasonal variability. OCO observations will permit the collection of spatially resolved, high resolution spectroscopic observations of CO2 and O2 absorption in reflected sunlight over both continents and oceans. OCO has three bore-sighted, high resolution, grating spectrometers which share a common telescope with similar optics and electronics. A 0.765 μm channel will be used for O2 observations, while the weak and strong CO2 bands will be observed with 1.61 μm and 2.06 μm channels, respectively. The OCO spacecraft circular polar orbit will be sun-synchronous with an inclination of 98.2 degrees, mean altitude of 705 km and 98.9 minute orbit period.
Journal Article

Development of the Orbiting Carbon Observatory Instrument Thermal Control System

2008-06-29
2008-01-2065
The Orbiting Carbon Observatory (OCO) will carry a single science instrument scheduled for launch on an Orbital Sciences Corporation LeoStar-2 architecture spacecraft bus in December 2008. The science objective of the OCO instrument is to collect spaced-based measurements of atmospheric CO2 with the precision, resolution, and coverage needed to identify CO2 sources and sinks and quantify their seasonal variability. The instrument will permit the collection of spatially resolved, high resolution spectroscopic observations of CO2 and O2 absorption in reflected sunlight over both continents and oceans. These measurements will improve our ability to forecast CO2 induced climate change. The instrument consists of three bore-sighted, high resolution grating spectrometers sharing a common telescope with similar optics and electronics.
Journal Article

Thermal Control System of the Moon Mineralogy Mapper Instrument

2008-06-29
2008-01-2119
The Moon Mineralogy Mapper (M3) instrument is one in a suite of twelve instruments which will fly onboard the Indian Chandrayaan-1 spacecraft scheduled for launch in 2008. Chandrayaan-1 is India's first mission to the Moon and is being managed by the Indian Space Research Organization (ISRO) in Bangalore, India. Chandrayaan-1 overall scientific objective is the photo-selenological and the chemical mapping of the Moon. The primary science objective of the M3 instrument is the characterization and mapping of the lunar surface composition in the context of its geologic evolution. Its primary exploration goal is to assess and map the Moon mineral resources at high spatial resolution to support future targeted missions. It is a “push-broom” near infrared (IR) imaging spectrometer with spectral coverage of 0.4 to 3.0 μm at 10 nm resolution with high signal to noise ratio, spatial and spectral uniformity.
Technical Paper

Thermal Design of the Tropospheric Emission Spectrometer Instrument

2000-07-10
2000-01-2274
The Tropospheric Emission Spectrometer (TES) is a cryogenic instrument which will be launched on NASA's Earth Observation System (EOS) Chemistry Platform in the year 2003. The overall mission lifetime for the instrument is 5 years with an additional period of 2 years required for ground test and calibration. The EOS Chemistry Platform will be placed in a sun-synchronous near-circular polar orbit with an inclination of 98.2 degrees and a mean altitude of 705 km. The overall objective of TES is the investigation and quantification of global climate change, both natural and anthropogenic. It is a high resolution infrared imaging (1×16 pixels) Fourier Transform Spectrometer with spectral coverage of 3.3-15.4 μm at a spectral resolution of 0.10 cm−1 or 0.025 cm−1 intended for the measurement and profiling of essentially all infrared-active molecules present in the Earth's lower atmosphere (0-30+ km).
Journal Article

On-Orbit Performance of the Moon Mineralogy Mapper Instrument

2009-07-12
2009-01-2390
Launched on India's Chandrayaan-1 spacecraft on October 22, 2008, JPL's Moon Mineralogy Mapper (M3) instrument has successfully completed over six months of operation in space. M3 is one in a suite of eleven instruments, six of which are foreign payloads, flying onboard the Indian spacecraft. Chandrayaan-1, managed by the Indian Space Research Organization (ISRO) in Bangalore, is India's first deep space mission. Chandrayaan-1 was launched on the upgraded version of India's Polar Satellite Launch Vehicle (PSLV-XL) from the Satish Dhawan Space Centre, SHAR, Sriharikota, India. The primary science objective of the M3 instrument is the characterization and mapping of the lunar surface composition in the context of its geologic evolution. Its primary exploration goal is to assess and map the Moon mineral resources at high spatial resolution to support future targeted missions.
Technical Paper

Thermal Design and On-Orbit Performance of the Multi-Angle Imaging SpectroRadiometer

2001-07-09
2001-01-2262
The Multi-angle Imaging SpectroRadiometer (MISR) instrument was launched aboard NASA’s Earth Observing System (EOS) Terra spacecraft on December 18, 1999. The overall mission design lifetime for the instrument is 6 years. The EOS Terra spacecraft was placed in a sun-synchronous near-circular polar orbit with an inclination of 98.3 degrees and a mean altitude of 705 km. The overall objective of MISR is to provide a means to study the ecology and climate of Earth through the acquisition of global multiangle imagery on the daylit side of Earth. MISR views the sunlit Earth simultaneously at nine widely spaced angles, collects global images with high spatial detail in four colors at every angle. The images acquired, once calibrated, provide accurate measurements of brightness, contrast and color of reflected sunlight.
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