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.

Space imagery provides a unique resource for addressing environmental challenges associated with land cover change, land use, disaster relief, deforestation, regional planning and global change research. At Ball Aerospace, we are developing the Compact Hyperspectral Prism Spectrometer (CHPS) as a candidate imaging spectrometer technology for insertion into future Sustainable Land Imaging missions. The 2013 NRC report Landsat and Beyond: Sustaining and Enhancing the Nations Land Imaging Program recommended that the nation should "maintain a sustained, space-based, land-imaging program, while ensuring the continuity of 42-years of multispectral information." In support of this, NASA's Sustainable Land Imaging-Technology (SLI-T) program aims to develop technology for a new generation of smaller, more capable, less costly payloads that meet or exceed current Landsat imaging capabilities. CHPS is designed to meet these objectives, providing high-fidelity visible-to-shortwave spectroscopic information. CHPS supports continuity of legacy Landsat data products, but also, provides a path to enhanced capabilities in support of land, inland waters, and coastal waters science. CHPS features full aperture full optical path calibration, extremely low straylight, and low polarization sensitivity; all crucial performance parameters for achieving the demanding SLI measurement objectives. In support of our space-borne instrument development, we have developed an airborne instrument to provide representative spectroscopic data and data products. Now in the final year of this 3-year development program, we have completed our initial engineering airborne flights and are beginning science flights. We present initial results from laboratory characterization & calibration and from our engineering flights and close with an overview of instrument performance.

To address mission risk and cost limitations the US has faced in putting a much needed Doppler wind lidar into space, Ball Aerospace and Technologies Corp, with support from NASA’s Earth Science Technology Office (ESTO), has developed the Optical Autocovariance Wind Lidar (OAWL), designed to measure winds from aerosol backscatter at the 355 nm or 532 nm wavelengths. Preliminary proof of concept hardware efforts started at Ball back in 2004. From 2008 to 2012, under an ESTO-funded Instrument Incubator Program, Ball incorporated the Optical Autocovariance (OA) interferometer receiver into a prototype breadboard lidar system by adding a laser, telescope, and COTS-based data system for operation at the 355 nm wavelength. In 2011, the prototype system underwent ground-based validation testing, and three months later, after hardware and software modifications to ensure autonomous operation and aircraft safety, it was flown on the NASA WB-57 aircraft. The history of the 2011 test flights are reviewed, including efforts to get the system qualified for aircraft flights, modifications made during the flight test period, and the final flight data results. We also present lessons learned and plans for the new, robust, two-wavelength, aircraft system with flight demonstrations planned for Spring 2016.

Climate monitoring and natural disaster rapid assessment require baseline measurements that can be tracked over time to distinguish anthropogenic versus natural changes to the Earth system. Absolute calibration and validation of Earth-observing sensors is needed to allow for comparison of temporally separated data sets and to provide accurate information to policy makers. The Ball Experimental Sea Surface Temperature (BESST) radiometer was designed and built by Ball Aerospace to provide a well calibrated measure of sea surface temperature (SST) from an unmanned aerial system (UAS). BESST utilizes an uncooled microbolometer array and on-board calibrated black bodies to provide an accurate remote skin temperature measurement over water in a small, modular, light-weight and low power package. This paper will demonstrate the capabilities of the sensor using flight data and discuss current progress with integrating the payload to a small UAS. The results from measurements over the BP Deep Water Horizon oil spill will be included to show capabilities for disaster assessment. The combination of a light-weight, low power sensor and the autonomous extended flight capabilities of the UAS allow for more frequent, cost effective, and higher resolution data for SST than is currently available. BESST on a UAS will provide validation for monitoring systems as well as augment the data with higher resolution information near coastal regions, hot spots, or disaster areas.

Ball Aerospace has field tested an Engineering Design Unit (EDU) of a Low Light Imager (LLI) instrument capable of high dynamic range imaging in the Visible to Near Infrared (VNIR) wavelength range. The instrument design is wellsuited to imaging scenes at low illumination levels or with radiance levels spanning a high dynamic range, including night scenes with clouds or anthropogenic light sources, and scenes that span the earth's terminator. A novel operating mode autonomously sets gains individually for each pixel and continuously updates the settings. Utilizing this scheme, the LLI EDU achieves a measured dynamic range > 107 in each image pixel of a scene. The upper and lower ends of the LLI dynamic range enable imaging of scenes illuminated by full sunlight or by a quarter moon only, as well as terminator scenes that span the two. The modular instrument configuration facilitates designs with different total Fields of View, including a three-module design with a cross-track FOV of 113 degrees. Testing and validation performed on the EDU include stray light testing, calibration and acquisition of ground images from an airborne platform. Radiometric test results demonstrate compliance with all radiometric requirements for the day/night imager for the National Polar Orbiting Environmental Spacecraft and Sensor (NPOESS) program.

A new heliostat facility at Ball Aerospace and Technologies Corporation (BATC) in Boulder, CO will allow the use of the sun as the source in the calibration of earth observing sensors. The solar spectrum is the basic energy source for such instruments; therefore it is advantageous to perform initial ground radiometric calibrations using the sun. Using this method for preflight radiometric calibration reduces uncertainties caused by the spectral mismatch between the preflight and in-flight calibration, especially in the case in which a solar diffuser is the in-flight calibration method. This method also reduces stray light concerns as the instrument diffuser is measured in situ with the same radiance level it sees on orbit. This paper presents the design of a heliostat test facility which tracks the sun and directs the solar beam into a thermal vacuum chamber, allowing the instrument under test to be kept in a safe, clean and controllable environment. Design considerations that affect the uniformity and transmission of the system are discussed. The opto-mechanical logistics of creating a heliostat that will deliver a 13-inch solar beam into a thermal vacuum chamber are also presented. This facility is currently under construction at BATC and is expected to be operational by the end of 2008.

BATC has developed a new stray light test facility (SLTF) and performed initial tests demonstrating its capabilities. The facility interior is nearly all black and is a Class 5 cleanroom. Coupled with a double cylindrical chamber that reflects the specular light away from the instrument under test, the stray light control in the facility is excellent. The facility was designed to be able to test a wide variety of instruments at a range of source angles from in-field to large off-axis angles. Test results have demonstrated PST performance below 1E-9.

A small, low mass and low power imaging spectrometer for airborne remote sensing of atmospheric and surface properties called the prototype airborne visible imaging spectrometer (PAVIS) has been designed, constructed, and field-tested by the airborne sensors initiative team at Ball Aerospace & Technologies Corp. Originally a breadboard spectrometer, PAVIS was developed to validate in the laboratory that a large concave grating on a moderately aspheric surface with minimal scattering could be fabricated, and that both spectral and spatial performance could be optimized simultaneously. The airborne sensor is being developed to demonstrate that useful scientific data approaching the quality of AVIRIS and the MODIS airborne simulator whiskbroom scanning spectrometers can be obtained with a compact pushbroom imaging spectrometer.

The Passive A-Band Wind Sounder (PAWS) project is funded through NASA's Instrument Incubator Program (IIP). The objective of PAWS is to demonstrate an instrument concept for measuring wind speed profiles in the troposphere using Doppler shifts in selected oxygen absorption lines. PAWS is a daytime-only approach, but has the potential to provide better wind data than is currently available with significantly lower cost, risk, and platform requirements than lidar. This paper will provide an overview of the PAWS approach and progress on the instrument development.

The Airborne Sensors Initiative (ASI) at Ball Aerospace & Technologies Corp. (BATC) specializes in airborne demonstration of internally-developed instrument concepts and innovative remote sensing technologies. In December 2006, ASI flew an environmental remote sensing suite consisting of the Low Light Imager (LLI) and Prototype Airborne Visible Imaging Spectrometer (PAVIS), both of which are operated using a pushbroom approach. LLI is designed for nighttime or high dynamic range imaging. It is capable of yielding 10(7) dynamic range and offers quality images amid illumination extending from a 1/4 moon to full sunlight and with autonomous operation. PAVIS is an imaging spectrometer based on the Dyson design and exhibits a 200 nm spectral bandwidth tunable within 400 - 850 nm. Developed internally to demonstrate promising remote sensing capabilities, these small, low-mass and low-power instruments are prepared for aircraft flight and are currently being used in the field to acquire scientific data. The LLI/PAVIS instrument suite has been utilized to collect airborne urban and rural imagery, as well as spectral information about the Great Salt Lake area, western Colorado, and ancient lava flows in southern Idaho. Highlights of the instrument design and ensuing data from previous flights are presented herein.

An imaging polarimeter for sensing of aerosol scattering and other atmospheric phenomena has been constructed and tested. The instrument is a testbed for a multispectral system architecture, in which spectral channels are added in a modular fashion using dichroic beamspltters and dedicated detectors. The testbed operates in a pushbroom scanning mode, with two co-boresighted optical trains. Each optical train features a narrow-band filter, an intermediate image at a slit, collimating optics, an appropriately oriented Wollaston prism, and two linear detector arrays. Consequently, the testbed is capable of determining the first three Stoke components (linear polarization) at a single wavelength. We describe calibration and field testing and present preliminary data analysis results.