The Geostationary Environment Monitoring Spectrometer (GEMS), an ultraviolet and visible imaging spectrometer, provides air-quality information over a large area of the Asia Pacific region with a high spatiotemporal resolution. To assure the reliability of trace gas retrieval, accurate knowledge of the spectral response function (SRF) is critical for spectral calibration as well as retrieval algorithms. Here, we characterize the GEMS SRF using prelaunch SRFs obtained with the monochromatic laser measurements during the ground test and inflight SRFs retrieved using the solar irradiance measurements after the launch. The prelaunch SRFs are analyzed in terms of shape (skewness and kurtosis), width, and under-sampling and show that the full-width at half-maximum is smaller than 0.6 nm with a maximum of 0.589 nm. The variations along both the spectral and spatial directions are smooth and within 3.65%, indicating a highly homogenous and stable optical system of GEMS. To characterize the prelaunch SRFs and monitor the behavior of inflight SRFs, we applied several analytical functions including asymmetric super Gaussian (ASG) and hybrid Gaussians to the prelaunch SRFs. The spectral fitting of the measured GEMS irradiance with a reference spectrum shows that the ASG to be the best representative of the GEMS SRFs. The inflight SRFs, retrieved with the GEMS irradiances and the ASG, agree well with the prelaunch SRFs, suggesting that the inflight spectral performance and characteristics of GEMS are similar to those investigated from the on-ground characterization.

The successful launch of Geostationary Environment Monitoring Spectrometer (GEMS) onboard the Geostationary Korea Multipurpose Satellite 2B (GK-2B) opens up a new possibility to provide daily air quality information for trace gases and aerosols over East Asia with high spatiotemporal resolution. As a part of major efforts to calibrate and validate the performance of the GEMS, accurate characterization of the spectral response functions (SRFs) is critical. The characteristics of preflight SRFs examined in terms of shape, width, skewness, and kurtosis vary smoothly along both the spectral and spatial direction thanks to highly symmetrical optic system of GEMS. While the preflight SRFs are determined with high accuracy, there is possibility of changes of in-flight SRFs during the harsh launch processes and/or operations over the mission lifetime. Thus, it is important to verify the in-flight SRFs after launch and to continue monitoring of their variability over time to assure the reliable trace gases retrievals. Here, we retrieve the in-flight SRFs for all spectral and spatial domain of the GEMS using spectral fitting of observed daily solar measurement and high-resolution solar reference spectrum. A variety of analytic model functions including hybrid form of Gaussian and flat-topped function, asymmetric super Gaussian, Voigt function are tested to determine the best representative function for GEMS SRF. The SRFs retrieved from early solar irradiances measured during the in-orbit tests agree well with the preflight SRFs indicating that no significant change occurred during the launch process. Continuous monitoring of the in-flight SRF is planned, using daily solar irradiances to investigate the temporal variation along with spectral and spatial directions. The detailed results of the in-flight SRF retrieval are to be presented.

The Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in February 2020 to monitor air quality (AQ) at an unprecedented spatial and temporal resolution from a geostationary Earth orbit (GEO) for the first time. With the development of UV–visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO, and aerosols) can be obtained. To date, all the UV–visible satellite missions monitoring air quality have been in low Earth orbit (LEO), allowing one to two observations per day. With UV–visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be on board the Geostationary Korea Multi-Purpose Satellite 2 (GEO-KOMPSAT-2) satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager 2 (GOCI-2). These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO) and ESA’s Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS).

The Wide Field Infrared Survey Telescope (WFIRST), NASA's next decadal astrophysics observatory, will enable advances in astrophysics by providing a large-scale survey capability in infrared wavelengths. The observatory is designed to capture data that will allow astronomers to unlock the mysteries of the universe, answering high-priority scientific questions related to the evolution of the universe and the habitability of exoplanets. Using a 2.4 m (7.9 ft) primary mirror, WFIRST will capture comparable quality images to the Hubble Space Telescope, but with more than 100 times the field of view, enabling the observatory to conduct comprehensive and efficient surveys of the infrared sky. Scientists estimate WFIRST has the potential to examine a billion galaxies over the course of its mission. Ball Aerospace was selected as NASA's partner to design and develop the Wide Field Instrument (WFI) Opto-Mechanical Assembly for the WFIRST mission. The optical-mechanical assembly, which includes the optical bench, thermal control system, precision mechanisms, optics, electronics, and the relative calibration system, provides the stable structure and thermal environment that enables the wide-field, high quality observations of WFI. Ball's innovative design uses heritage hardware to unfold the incoming light, providing cost and schedule savings to the mission. In this paper, we present an overview of the WFI design, which completed its preliminary design review in June 2019. The overview includes a discussion of the design process, including several of the trade studies completed that led to the unfolded optical path architecture for the instrument design. The current state of the design is shown.

To consistently observe deteriorating air quality over East Asia, the National Institute of Environmental Research, Republic of Korea, is planning to launch an environmental observation sensor, the Geostationary Environment Monitoring Spectrometer (GEMS), onboard the GK-2B satellite (a successor to the GeoKOMPSAT-1) in late 2019. GEMS is a hyperspectral spectrometer that covers the ultraviolet-visible range (300 to 500 nm) with full-width at half-maximum of 0.6 nm. It has been designed for the observation of air pollutants and short-lived climate pollutants. GEMS captures images at hourly intervals in the daytime, alternating with the Geostationary Ocean Color Imager-II every 30 min. Over the Seoul Special Metropolitan area, South Korea, the spatial sampling resolution of GEMS is 3.5 x 8 km (north-south and east-west, respectively). There are 16 baseline products, including aerosol optical depth and the vertical column density of trace gases such as nitrogen dioxide, sulfur dioxide, formaldehyde, and ozone. Research continues into additional applications (e.g., ground-level concentrations and emissions). (C) The Authors.

REMI (Reduced Envelope Multispectral Imager) is a new instrument developed by Ball Aerospace specifically for the Sustained Land Imaging (SLI) program. The goal of REMI is to meet the current Landsat mission requirements with a much smaller volume, lower cost payload. A lower single unit recurring cost enables economies of scale on multiple builds by leveraging non-recurring engineering costs. This lower cost enables multiple copies on-orbit at the same time for improved temporal sampling, an innovative approach to space segment reliability, and more frequent technology onramps. REMI achieves miniaturization through use of a common aperture for all spectral bands. REMI features a pointing mechanism that compensates for platform and ground motion while using cross-track, step-stare pointing to produce contiguous ground coverage in all spectral bands. The status of the REMI development and airborne flight testing will be presented.

The Geostationary Environmental Monitoring Spectrometer (GEMS) and the Tropospheric Emissions: Monitoring of Pollution (TEMPO) instruments will provide a new capability for the understanding of air quality and pollution. Ball Aerospace is the developer of these UV/Vis Hyperspectral sensors. The GEMS and TEMPO instrument use proven remote sensing techniques and take advantage of a geostationary orbit to take hourly measurements of their respective geographical areas. The high spatial and temporal resolution of these instruments will allow for measurements of the complex diurnal cycle of pollution driven by the combination of photochemistry, chemical composition and the dynamic nature of the atmosphere. The GEMS instrument was built for the Korea Aerospace Research Institute and their customer, the National Institute of Environmental Research (NIER) and the Principle Investigator (PI) is Jhoon Kim of Yonsei University. The TEMPO instrument was built for NASA under the Earth Venture Instrument (EVI) Program. NASA Langley Research Center (LaRC) is the managing center and the PI is Kelly Chance of the Smithsonian Astrophysical Observatory (SAO).

The Tropospheric Emissions, Monitoring of Pollution (TEMPO) program is deploying a hosted GEO imaging spectrometer that measures daily air quality over a large geographic area. In this paper, we provide an overview of the mission and we detail instrument design challenges associated with being a hosted payload where spacecraft attitude control and jitter management is normally of less concern. We discuss the scan mechanism employed to cover the imaging spectrometer's field of regard and to reject host disturbances and minimize pointing errors. Finally, the ground support and mission operations are summarized, including image navigation and registration (INR) and tailoring of the scan commands for efficient coverage of Greater North America (GNA).

Greatly improved understanding of areas and objects of interest can be gained when real time, full-motion Flash LiDAR is fused with inertial navigation data and multi-spectral context imagery. On its own, full-motion Flash LiDAR provides the opportunity to exploit the z dimension for improved intelligence vs. 2-D full-motion video (FMV). The intelligence value of this data is enhanced when it is combined with inertial navigation data to produce an extended, georegistered data set suitable for a variety of analysis. Further, when fused with multispectral context imagery the typical point cloud now becomes a rich 3-D scene which is intuitively obvious to the user and allows rapid cognitive analysis with little or no training. Ball Aerospace has developed and demonstrated a real-time, full-motion LIDAR system that fuses context imagery (VIS to MWIR demonstrated) and inertial navigation data in real time, and can stream these information-rich geolocated/fused 3-D scenes from an airborne platform. In addition, since the higher-resolution context camera is boresighted and frame synchronized to the LiDAR camera and the LiDAR camera is an array sensor, techniques have been developed to rapidly interpolate the LIDAR pixel values creating a point cloud that has the same resolution as the context camera, effectively creating a high definition (HD) LiDAR image. This paper presents a design overview of the Ball TotalSight™ LIDAR system along with typical results over urban and rural areas collected from both rotary and fixed-wing aircraft. We conclude with a discussion of future work.

The Ball Aerospace Total SightTM Flash LiDAR and real time processing system provides real-time digital elevation map creation and dissemination. This unique capability is critical for mapping applications where data latency cannot be tolerated. These applications include rapid response disaster relief efforts, improved battlefield characterization and more timely and accurate military targeting. The creation of real time digital elevation maps from LiDAR data is also beneficial in streamlining production mapping jobs such as corridor mapping. The Total SightTM system is the result of 5 years of development of sensor and processing technologies. The system has been flown on multiple airborne platforms for missions including landing hazard mapping and identification, urban and mountain terrain mapping and characterization, power line mapping, 3-dimensional target tracking and foliage penetration. The system is highly configurable to meet a variety of customer and mission requirements. The Ball Aerospace Total SightTM sensor, processing chain, and resulting imagery are discussed.

th Generation Flash Ladar system which produces real-time, 3-dimensional (3D) video in all lighting conditions has been demonstrated to be a significant enabler to enhance the mission capabilities of Unmanned Aerial Vehicles (UAVs). These new capabilities include enhanced Intelligence, Reconnaissance and Surveillance (ISR), Automated Target Recognition (ATR), improved situational awareness, GPS denied (terrain relative) navigation, 3D surface mapping, surface change detection (detection of buried improvised explosive devices), camouflage penetration, autonomous aerial refueling and autonomous landing. Ball Aerospace 5 th Generation Flash Ladar system has benefited from over 6 years of development, is compact, modular, and has been demonstrated to be easily integrated and flight-tested on both fixed-wing and rotorcraft with different optical configurations. This paper presents the results of airborne test activities and sample imagery of our 5 th Generation system and discusses options for repackaging and integrating the system into UAV platforms. I. Introduction all Aerospace has significant experience in providing ladar systems for remote sensing applications. NASA’s CALIPSO lidar was built by Ball and has celebrated a number of operational milestones, including an extension of the 3-year initial mission lifetime and over 1 billion laser firings and associated atmospheric measurements. Further, Ball Aerospace is developing the flash ladar navigation system for NASA’s space exploration missions. These programs leverage Ball’s extensive understanding of ladar systems, real time image processing algorithms, guidance, navigation and control algorithms, laser system engineering, and the phenomenology being exploited. 1

Future missions to Mars will offer the opportunity to continue the search for organic molecules accessible from the surface, and to better quantify the cycling of volatile elements through geochemical pathways. This presentation describes an analytical instrument suite that is designed to measure elemental, isotopic, and potential organic signatures contained in the atmosphere and near surface reservoirs on Mars. The Mars analytical chemistry experiment (MACE) combines two unique mass-spectrometer-based instruments to accomplish these measurements. The first instrument combines a sample handling system with a reusable pyrolysis oven for processing solid materials. Evolved volatile gases from the pyrolyzer are either oxidized for elemental analysis, or sent through a preconcentrator into a 2D gas chromatograph for separation of organics. The processed gas stream is then sent to a high resolution dynamic time-of-flight mass spectrometer for detection. The second instrument is designed primarily for direct atmospheric measurements, using a combination of catalyst beds, getters, and cryogenic traps to separate and concentrate species of interest, such as noble gases. Concentrated gases are subsequently detected with a second, dedicated static mass spectrometer to avoid possible contamination from the pyrolysis of organics in the first process. A breadboard version of each of these instruments has been demonstrated in the laboratory. In this presentation, we discuss the design, applicability, and capabilities of the MACE suite in more detail

A ship emission plume experiment was conducted about 100 km off the California coast during the NOAA Intercontinental Transport and Chemical Transformation (ITCT) 2K2 airborne field campaign. Measurements of chemical species were made from the NOAA WP‐3D aircraft in eight consecutive transects of a ship plume around midday during 2.5 hours of flight. The measured species include NOx, HNO3, peroxyacetylnitrate (PAN), SO2, H2SO4, O3, CO, CO2, nonmethane hydrocarbons (NMHC), and particle number and size distributions. Observations demonstrate a NOx lifetime of ∼1.8 hours inside the ship plume compared to ∼6.5 hours (at noontime) in the moderately polluted background marine boundary layer of the experiment. This confirms the earlier hypothesis of highly enhanced in‐plume NOx destruction. Consequently, one would expect the impact of ship emissions is much less severe than those predicted by global models that do not include rapid NOx destruction. Photochemical model calculations suggest that more than 80% of the NOx loss was due to the NO2 + OH reaction; the remainder was by PAN formation. The model underestimated in‐plume NOx loss rate by about 30%. In addition, a comparison of measured to predicted H2SO4 in the plumes suggests that the photochemical model predicts OH variability reasonably well but may underestimate actual values. Predictions of in‐plume O3 production agree well with the observations, suggesting that model‐predicted peroxy radical (HO2 + RO2) levels are reasonable. The model estimated ozone production efficiency ranges from 6 to 30. The largest model bias was seen in the comparison with measured HNO3. The model overestimated in‐plume HNO3 by about a factor of 6. This is most likely caused by underestimated HNO3 sinks possibly involving particle scavenging. However, limited data availability precluded a conclusive test of this possible loss process.