Engineering topics
Mouroulis, Pantazis
Publications and source records attributed to Mouroulis, Pantazis.
Surface Biology and Geology (SBG) Visible to Short Wavelength Infrared (VSWIR) Wide Swath Instrument Concept
The 2017 Decadal Survey: Thriving on Our Changing Planet, A Decadal Strategy for Earth Observation from Space has called new observations including global coverage Visible to Short Wavelength Infrared (VSWIR) Wide Swath (WS) imaging spectroscopy measurements as part of the Surface Biology and Geology (SBG) Designated Observable. The SBG VSWIR-WS along with the companion SBG Thermal Infrared (TIR) imager is an important element of NASA’s larger Earth System Observatory (ESO).
Surface Biology and Geology (SBG) Visible to Short Wavelength Infrared (VSWIR) Wide Swath Instrument Concept
The 2017 Decadal Survey: Thriving on Our Changing Planet, A Decadal Strategy for Earth Observation from Space has called new observations including global coverage VSWIR Wide Swath (VSWIR-WS) imaging spectroscopy measurements as part of the Surface Biology and Geology (SBG) Designated Observable. The SBG VSWIR-WS along with the companion SBG Thermal Infrared (TIR) imager is an important element of NASA’s larger Earth System Observatory (ESO).
Airborne Visible/Infrared Imaging Spectrometer 3 (AVIRIS-3)
The Airborne Visible/Infrared Imaging Spectrometer 3 (AVIRIS-3) is the third of the NASA AVIRIS spectrometer series and is being developed in parallel with the Compact Wide-swath Imaging Spectrometer II (CWIS-II) for the University of Zurich, Switzerland. The core spectrometer of AVIRIS-3 is a copy of the optically fast, F/1.8 Dyson imaging spectrometer used by the Earth Surface Mineral Dust Source Investigation (EMIT) that is in development and scheduled for launch to the International Space Station (ISS) in 2022. AVIRIS-3 is intended to provide state-of-the-art imaging spectroscopy measurements for NASA science and application through the next decade and beyond. AVIRIS-3 uses the EMIT spectrometer design interfaced with a scaled two mirror telescope enclosed in a portable vacuum vessel to enable measurements from airborne platforms ranging from a Twin Otter to a business jet or a NASA ER-2. AVIRIS-3 is a cryogenic instrument with advanced system control and real-time onboard spectroscopic data processing algorithms evolved from AVIRIS-NG. The spectral range of AVIRIS-3 is 380 to 2500 nm with 7.4 nm sampling. The radiometric range is from 0 to max terrestrial Lambertian radiance with higher signal-to-noise ratio performance than AVIRIS-Classic or AVIRIS-Next Generation. The spatial field-of-view is 39.5 degrees with 0.56 milliradian sampling. This paper describes the design and development of AVIRIS-3 and presents its characteristics in comparison to the previous generation imaging spectrometers.
Solar-powered Outer Solar System SmallSat (OS4) Architecture and Technologies
No abstract provided
Solar-powered Outer Solar System SmallSat (OS4) Architecture and Technologies
No abstract provided
Solar-powered Outer Solar System SmallSat (OS4) Architecture and Technologies
No abstract provided
Snow and Water Imaging Spectrometer: Final Instrument Characterization
The Snow and Water Imaging Spectrometer (SWIS) is a science-grade imaging spectrometer and telescope system suitable for CubeSat applications, spanning a 350-1700 nm spectral range with 5.7 nm sampling, a 10 degree field of view and 0.3 mrad spatial resolution. The system operates at F/1.8, providing high throughput for low-reflectivity water surfaces, while avoiding saturation over bright snow or clouds. The SWIS design utilizes heritage from previously demonstrated instruments on airborne platforms, while advancing the state of the art in compact sensors of this kind in terms of size and spectral coverage. Through frequent repeat observations from space at a moderate spatial resolution, SWIS can address key science questions concerning aquatic and terrestrial ecosystem changes, cryosphere warming and melt behavior, cloud and atmospheric science, and potential impacts of climate change and human activities on the environment. We review the optical design and innovations and key technologies developed for this instrument, as well as its measured optical performance. We discuss the radiometric calibration characterization, including detector linearity, flat field correction, and SNR. Finally, we discuss stray light modeling and the development of a focused ghost removal algorithm, which is tested and supported by laboratory results.
Recent Developments in Tolerancing Methods for Imaging Spectrometers
We discuss detailed tolerancing methods developed for imaging spectrometers at NASA Jet Propulsion Laboratory, California Institute of Technology using the Earth Surface Mineral Dust Source Investigation (EMIT) imaging spectrometer as an illustrative example. We tolerance five metrics simultaneously: along-track response function, cross-track response function, spectral response function, spectral centroid uniformity, and spatial centroid uniformity. A method to calculate tolerancing sensitivities for each metric directly, a method to statistically combine Monte Carlo files from multiple tolerancing runs, and an example summary error budgets that communicate the key and driving tolerances for each metric are discussed. These methods facilitate rapid and semi-automated assessment of the predicted performance of imaging spectrometer systems from design through to assembly and launch life cycle, using metrics that are directly relevant to the extraction of accurate spectroscopic data from these instruments.
Optical Design of the Earth Surface Mineral Dust Source Investigation (EMIT) Imaging Spectrometer
The Earth Surface Mineral Dust Source Investigation (EMIT) instrument is a high fidelity imaging spectrometer developed to characterize surface mineralogy of the Earth’s dust source regions over the spectral range of 380- 2500 nm and spectral sampling of 7.4 nm. EMIT will close the current knowledge gap in dust source mineral composition by collecting over 1 billion high signal-to-noise ratio spectra in this region of our planet. These new measurements will be used in conjunction with state-of-the-art Earth System Models to understand and reduce the uncertainty in the radiative forcing effect of mineral dust aerosols. EMIT will be deployed on the International Space Station that has an orbit that is well suited for measuring the arid land regions of the Earth. The optical design utilizes a Dyson spectrometer to reduce volume and mass for a fast (F/1.8) and wide swath (1240 samples) optical system. An overview of the EMIT optical design, development, and current status are discussed.
Ultra-Compact Imaging Spectrometer Moon (UCIS-Moon) For Lunar Surface Missions: Optical, Optomechanical, and Thermal Design
The Ultra-Compact Imaging Spectrometer Moon (UCIS-Moon) instrument is an imaging spectrometer designed for integration with a lander or rover for lunar surface science missions. Operating over a 600-3600 nm spectral range with 10 nm sampling and 1.15 mrad IFOV, UCIS-Moon is capable of detecting spectral absorptions from common lunar minerals, OH species, molecular H2O, water ice, organics, and placing mineral identifications within an established geologic context at the cm to m scale. We present an instrument design capable of surviving the harsh lunar environment in the daytime with temperatures as high as 370 K, while providing high-quality spectral data.
Compact Imaging Spectrometer for Planetary Missions
We report on the design performance of a compact imaging spectrometer suitable for planetary missions with U-Class spacecraft. It is a fast (F/1.9) and wide field instrument covering the range 600-3600 nm with 10 nm sampling and a 1000 pixel by 18m wide slit. The spectrometer is designed for use with a digital readout focal plane array that further aids miniaturization.
SmallSats Beyond Saturn Without Radioisotopes: A Preliminary Assessment
UNKNOWN
The Earth Surface Mineral Dust Source Investigation: An Earth Science Imaging Spectroscopy Mission
The Earth Surface Mineral Dust Source Investigation, EMIT, is planned to operate from the International Space Station starting no earlier than the fall of 2021. EMIT will use visible to short wavelength infrared imaging spectroscopy to determine the mineral composition of the arid land dust source regions of the Earth to advance our knowledge of the radiative forcing effect of these aerosols. Mineral dust emitted into the atmosphere under high wind conditions is an element of the Earth system with many impacts to the Earth’s energy balance, atmosphere, surface, and oceans. The Earth’s mineral dust cycle with source, transport, and deposition phases are studied with advanced Earth System Models. Because the chemical composition, optical and surface properties of soil particles vary strongly with the mineral composition of the source, these models require knowledge of surface soil mineral dust source composition knowledge to accurately understand dust impacts on the Earth system now and in the future. At present, compositional knowledge of the Earth’s mineral dust source regions from existing data sets is uncertain as a result of limited measurements. EMIT will use spectroscopically derived surface mineral composition to update the prescribe boundary conditions for state-of-the-art Earth System Models. The EMIT-initialized models will be used to investigate the impact of direct radiative forcing in the Earth system that depends strongly on the composition of the mineral dust aerosols emitted into the atmosphere. These new measurements and related products will be used to address the EMIT science objectives and made available to the science community for additional investigations. An overview of the EMIT science, development, and mission is presented in this paper.
Low-Cost SmallSats to Explore to Our Solar System’s Boundaries (Interim Report)
UNKNOWN
Optical design of the Mapping Imaging Spectrometer for Europa (MISE)
e Mapping Imaging Spectrometer for Europa (MISE) is a high-throughput pushbroom imaging spectrometer designed for NASA’s planned flyby mission to Jupiter’s moon Europa. The MISE design utilizes heritage from previously demonstrated instruments on airborne platforms, while advancing the state of the art to operate within Europa’s challenging environment. The instrument operates at F/1.4 and covers a spectral range from 0.8 to 5 microns with 10 nm spectral sampling. Through high resolution mapping, MISE is designed to identify distributions of organics, salts, acid hydrates, water ice phases, altered silicates, radiolytic compounds, and warm thermal anomalies at global, regional, and local scales. Such distribution maps will help study surface and subsurface geologic processes, and assess the habitability of Europa’s ocean. We discuss the optical specifications and baseline performance of the MISE optical design.