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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1972

Apollo 17

This is the Press Kit that was given to the various media outlets that were interested in covering the Apollo 17 mission. It includes information about the moon, lunar science, concentrating on the planned mission. The kit includes information about the flight, and the trajectory, planned orbit insertion maneuvers, the extravehicular mission events, a comparison with the Apollo 16, a map of the lunar surface, and the surface activity, information about the Taurus-Littrow landing site, the planned science experiments, the power source for the experiment package and diagrams of some of the instrumentation that was used to perform the experiments.

Garrett, David↗
NASA NTRS2010

NASA Goddard Space Flight Center, on Behalf of the Fermi Large Area Telescope Collaboration

Because high-energy gamma rays can be produced by processes that also produce neutrinos, the gamma-ray survey of the sky by the Fermi (Gamma-ray Space Telescope offers a view of potential targets for neutrino observations. Gamma-ray bursts. Active Galactic Nuclei, and supernova remnants are all sites where hadronic, neutrino-producing interactions are plausible. Pulsars, pulsar wind nebulae, and binary sources are all phenomena that reveal leptonic particle acceleration through their gamma-ray emission. While important to gamma-ray astrophysics, such sources are of less interest to neutrino studies. This talk will present a broad overview of the constantly changing sky seen with the Large Area Telescope (LAT)on the Fermi spacecraft.

Thompson, David J.↗
NASA NTRS2011

Fermi Gamma-Ray Space Telescope: Highlights of the GeV Sky

Because high-energy gamma rays can be produced by processes that also produce neutrinos. the gamma-ray survey of the sky by the Fermi Gamma-ray Space Telescope offers a view of potenl ial targds for neutrino observations. Gamma-ray bursts. active galactic nuclei, and supernova remnants are all sites where hadronic, neutrino-producing interactions are plausible. Pulsars, pulsar wind nebulae, and binary sources are all phenomena that reveal leptonic particle acceleration through their gamma-ray emission. \Vhile important to gamma-ray astrophysics. such sources are of less interest to neutrino studies. This talk will present a broad overview of the constantly changing sky seen with the Large Area Telescope (LAT) on the Fermi spacecraft.

Thomspon, D. J.↗
NASA NTRS2008

Hail Disrometer Array for Launch Systems Support

Prior to launch, the space shuttle might be described as a very large thermos bottle containing substantial quantities of cryogenic fuels. Because thermal insulation is a critical design requirement, the external wall of the launch vehicle fuel tank is covered with an insulating foam layer. This foam is fragile and can be damaged by very minor impacts, such as that from small- to medium-size hail, which may go unnoticed. In May 1999, hail damage to the top of the External Tank (ET) of STS-96 required a rollback from the launch pad to the Vehicle Assembly Building (VAB) for repair of the insulating foam. Because of the potential for hail damage to the ET while exposed to the weather, a vigilant hail sentry system using impact transducers was developed as a hail damage warning system and to record and quantify hail events. The Kennedy Space Center (KSC) Hail Monitor System, a joint effort of the NASA and University Affiliated Spaceport Technology Development Contract (USTDC) Physics Labs, was first deployed for operational testing in the fall of 2006. Volunteers from the Community Collaborative Rain. Hail, and Snow Network (CoCoRaHS) in conjunction with Colorado State University were and continue to be active in testing duplicate hail monitor systems at sites in the hail prone high plains of Colorado. The KSC Hail Monitor System (HMS), consisting of three stations positioned approximately 500 ft from the launch pad and forming an approximate equilateral triangle (see Figure 1), was deployed to Pad 39B for support of STS-115. Two months later, the HMS was deployed to Pad 39A for support of STS-116. During support of STS-117 in late February 2007, an unusual hail event occurred in the immediate vicinity of the exposed space shuttle and launch pad. Hail data of this event was collected by the HMS and analyzed. Support of STS-118 revealed another important application of the hail monitor system. Ground Instrumentation personnel check the hail monitors daily when a vehicle is on the launch pad, with special attention after any storm suspected of containing hail. If no hail is recorded by the HMS, the vehicle and pad inspection team has no need to conduct a thorough inspection of the vehicle immediately following a storm. On the afternoon of July 13, 2007, hail on the ground was reported by observers at the VAB, about three miles west of Pad 39A, as well as at several other locations around Kennedy Space Center. The HMS showed no impact detections, indicating that the shuttle had not been damaged by any of the numerous hail events which occurred that day.

Lane, John E.↗
NASA NTRS2009

NASA TEERM Project: Corn Based Blast Media

Coatings removal is a necessary part of the maintenance, repair, and overhaul activities at many NASA centers and contractor support sites. Sensitive substrates, such as composites and thin aluminum alloys require special handling such as the use of chemical stripping, pneumatic hand sanding, or softer blast media. Type V, acrylic based PMB is commonly used to de-coat, strip, or de-paint the delicate substrates of the Solid Rocket Boosters (SRBs) currently used in support of the Shuttle and slated to be used in support of CxP.

Griffin, Chuck↗
NASA NTRS2015

Kinetic Monte Carlo Simulation of Oxygen Diffusion in Ytterbium Disilicate

Silicon-based ceramic components for next-generation jet turbine engines offer potential weight savings, as well as higher operating temperatures, both of which lead to increased efficiency and lower fuel costs. Silicon carbide (SiC), in particular, offers low density, good strength at high temperatures, and good oxidation resistance in dry air. However, reaction of SiC with high-temperature water vapor, as found in the hot section of jet turbine engines in operation, can cause rapid surface recession, which limits the lifetime of such components. Environmental Barrier Coatings (EBCs) are therefore needed if long component lifetime is to be achieved. Rare earth silicates such as Yb2Si2O7 and Yb2SiO5 have been proposed for such applications; in an effort to better understand diffusion in such materials, we have performed kinetic Monte Carlo (kMC) simulations of oxygen diffusion in Ytterbium disilicate, Yb2- Si2O7. The diffusive process is assumed to take place via the thermally activated hopping of oxygen atoms among oxygen vacancy sites or among interstitial sites. Migration barrier energies are computed using density functional theory (DFT).

Computer Simulation↗
NASA NTRS2023

Fire Station #3 Area, Solid Waste Management Unit (SWMU) 106 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Progress Report Kennedy Space Center, Florida

This Per-and Polyfluoroalkyl Substances (PFAS) Site Assessment (SA) Progress Report (SAPR) presents the activities and results associated with PFAS investigation in the Fire Station #3 (FS3) Area located at Kennedy Space Center (KSC), Florida. FS3 (formerly known as Fire Station #6) was previously designated as Solid Waste Management Unit (SWMU) 106 for legacy contaminants that were investigated and still being managed under KSC’s Resource Conservation and Recovery Act (RCRA) Corrective Action Program. This PFAS SA is being managed under SWMU 106 as the fire station was also identified as the potential source of PFAS to the environment in this area.

Sarah Damphouse↗
NASA NTRS2024

2023 Annual Long-Term Monitoring Report Vehicle Assembly Building Area

This report presents a summary of the groundwater monitoring activities that occurred in February 2024 at two sites in the Vehicle Assembly Building (VAB) Area Long-Term Monitoring (LTM) program at the John F. Kennedy Space Center, Florida. The two sites are Fire Station 3 (formerly Fire Station 6) (FS3) – Solid Waste Management Unit (SWMU) 106 and Launch Complex 39 Observation Gantry Area (LC39OGA) – SWMU 107.

VAB Long-Term Groundwater Monitoring↗
NASA NTRS1990

Activity and adaptation of nitrilotriacetate (NTA)-degrading bacteria: field and laboratory studies

Adaptation of bacterial activity for the degradation of nitrilotriacetate (NTA) was studied using natural sediment samples and an NTA-degrading bacterium (strain ATCC 29600). Sediment samples from a river with persistent levels of NTA had much higher NTA-degradative activity than comparable samples from a less contaminated control site. When sediment from the control site was exposed to high levels of NTA a 5 day lag preceded an abrupt increase in NTA degradation while strain 29600 colonized on sand and grown in the absence of NTA became induced within eight hours. The induction of strain 29600 was compared between bacteria in suspension and cells attached to sand. The sand-associated bacteria became induced 4 to 5 h before the planktonic suspension and displayed over threefold greater specific activity. Suspensions of strain 29600 became adapted within 8 h when placed in membrane diffusion chambers that were immersed within a municipal wastewater reactor containing NTA. These findings support the concept that induction is a part of the process of bacterial adaptation to degrade NTA and sand-associated bacteria can adapt more quickly to and have a greater degradative activity for NTA than planktonic cells.

NASA Discipline Number 04-10↗
NASA NTRS1990

Polarimetric SAR calibration experiment using active radar calibrators

Active radar calibrators are used to derive both the amplitude and phase characteristics of a multichannel polarimetric SAR from the complex image data. Results are presented from an experiment carried out using the NASA/JPL DC-8 aircraft SAR over a calibration site at Goldstone, California. As part of the experiment, polarimetric active radar calibrators (PARCs) with adjustable polarization signatures were deployed. Experimental results demonstrate that the PARCs can be used to calibrate polarimetric SAR images successfully. Restrictions on the application of the PARC calibration procedure are discussed.

Freeman, Anthony↗
NASA NTRS2000

Imagine the Universe: The Hidden Lives of Galaxies

Welcome to the fourth in a series of posters and activity booklets produced in conjunction with the Imagine the Universe! web site. The poster/booklet sets are intended to provide additional curriculum support materials for some of the subjects presented in the web site. The information provided for the educator in the booklet is meant to give the necessary background information so that the topic can be taught confidently to the students. The activities can be used to engage and excite students about the topic of galaxies in a number of disciplines and ways. The booklet and all activities can be photocopied and distributed for educational, non-commercial purposes.

Lochner, James C.↗
NASA NTRSDate not supplied

A Notional Artemis Lunar Surface Exploration Package (ArLSEP) based on the Gandalf Staff Platform

Introduction: The Artemis program is planning to deliver crew and cargo to the lunar surface, but there is no current package for supporting lunar in-struments and experiments similar to the Apollo Lunar Surface Exploration Package (ALSEP). This abstract provides a possible concept for such a package using the Gandalf Staff Platform as a common core. Gandalf Staff: The Gandalf Staff is an early prototype system developed over FY’21/FY’22 using NASA Science Technology Mission Directorate (STMD) Center Information Fund (CIF) grants to de-sign, build and test “proof-of-concept” components. These components include a 24v battery powered monopole that powers a suite of subsystems, including a Graphical User Interface (GUI) for crew, surface voice and data communications, Lunar Search and Rescue (LunaSAR) navigation and communications, LiDAR, field site external lighting, 360-degree camera, and a geothermal instrument for measuring sub-surface temperature gradient. The staff can be carried independently by an Extra-Vehicular Activity (EVA) astronaut, or can be mounted into a tripod for “hands free” support at a surface site being investigated. The staff can be attached to an external solar array and power storage system for long-duration operations. [1,2] ALSEP: An ASLEP flew on each mission Apollo 12 to Apollo 17. For Apollo 11, a simplified packaged called the Early Apollo Scientific Experiments Pack-age (EASEP) was flown. Each package included a “Central Station” that provided the power and communications connected to a variety of instruments and sensors. The power was provided by a Radioisotope Thermoelectric Generator (RTG) fueled by Plutoni-um-238 generating 70 watts of power (initially, decayed over time) [3]. The communications system provide for direct to Earth data transfer from the lunar surface. Each pack-age was stowed externally in the Lunar Module (LM) Scientific Equipment (SEQ) bay with a mass up to 163 kg (Apollo 17). The crew unloaded the ALSEP from the LM and deployed the instruments on the lunar surface. Although designed to operate for only 1 year, many sites operated for up to 8 years successfully [4]. The Active Seismic Experiment (ASE) included 3 geophones for detecting seismic waves created by mortars and thumpers deployed by the crew. Other active experiments measured the lunar atmosphere, the heat flow in the subsurface, the lunar gravity and potential gravity waves, the lunar magnetic field, the solar wind and plasma interactions in cislunar space. Passive experiments included collectors for dust and cosmic rays, and retroreflectors for precise measurements of distance using a laser from Earth. The ALSEP program continues to generate insights into lunar formation and evolution. ArLSEP Concepts: The lunar surface science package for the Artemis program will hopefully exceed the capability of the ALSEP. There are multiple issues for discussion leading to the design of a new ArLSEP, needing requirements definition from the science community, NASA mission architecture, and NASA budget planners. 1. Delivery Mechanism Two possible projects currently provide capability to deliver scientific cargo to the lunar surface: 1) the Commercial Lunar Payload Services (CLPS) [5] and the Human Landing System (HLS) [6, 7]. Each project is controlled by a different organization within NASA and budgeted with different criteria although both support lunar exploration. The HLS system delivers crew (and potentially cargo) to human landing sites. If an ArLSEP is “predeployed” to such a site, the design must include power (either from the vehicle or independently) to keep the electronics functioning until deployed by the crew. If an ArLSEP is delivered on a vehicle after the crew is present on the lunar surface, safety protocols require adequate distance from the humans for impact from descent propelled sur-face regolith ejecta. This distance can not exceed the capability of the crew to walk (if no rover) to the vehicle for ArLSEP deployment. 2. Overall Guidelines The general design of ArLSEP will likely follow the ALSEP with a common system for communications and power; however, significant architecture differences between Apollo and Artemis exist. Power: The RTG will not be available for early Artemis missions nor likely follow-on Lunar Exploration Transportation Services (LETS) missions [8]. Thus, ArLSEP power must be supplied by solar arrays with sufficient battery capability to “keep alive” necessary electronics during any lunar surface eclipse period. Communication: The Artemis program is developing a series of communications satellites for lunar orbit to provide surface transmission of data and voice to Earth. Called “LunaNET”, this network is component useful for ArLSEP since south polar locations may not always have direct “line-of-sight” to Earth [9]. 3. Concept of Operations (ConOps) The general ConOps for ArLSEP is to deliver the package to lunar surface before the crew arrives, and then have the crew deploy the package after some period of time. This requires coordinated design (for power systems) and launch window (for schedule) on both the cargo and crew missions. Once the ArLSEP is deployed, it will operate autonomously for a number of years. It should be designed to be EVA compatible for crew maintenance and upgrade. 4. Notional Design (for discussion purpose only) The landing site near the South Pole is expected to have no eclipse cycle exceeding 5 days, so the “keep alive” power is 144 hours (6 days to include margin). A 12v ArLSEP will use rechargeable LiFePO4 cells, which are common in the Electric Vehicle (EV) industry. With a current of 5 amps and a 125 watt system, the mass is about 90kg. The comm. system and structure adds another 10kg, thus the “Central Station” is approximately 100kg. The solar power is collected on four arrays (each 2m above the surface), and the entire ArLSEP is designed to stow in a 2m x 1m x 1m volume. The experiment and instrument design will vary for each installation and add mass to the total (although they are expected to fit within the 2m3 volume). Seismic wave generation will likely not be provided with mortars, thus an electric “thumper” will be required. Active instruments such as imaging systems and sensing instruments will benefit from the additional power and communication capability provided by ArLSEP. Passive systems such as retroreflectors, witness plates, and cosmic dust collectors can be added to either the landing vehicle and/or the ArLSEP. With repeated HLS missions to the same human site, the ArLSEP can be expanded and easily maintained for long duration science collection on the lunar surface.

ALSEP↗
NASA NTRS2024

Soil Interim Measures Implementation Report Q6 Radar Station – Solid Waste Management Unit 112 Locations of Concern 3 and 10 Kennedy Space Center, Florida

This report presents a summary of the soil interim measures (IM) implementation activities that occurred from January 23 through June 6, 2023, at the Q6 Radar Station (Q6RS) Solid Waste Management Unit (SWMU) 112, located at the John F. Kennedy Space Center (KSC), Florida. The site is monitored under KSC’s Resource Conservation and Recovery Act Corrective Action Program, which also meets the requirements of Chapter 62-780, Florida Administrative Code. Assessment activities have previously been performed at 10 Q6RS Locations of Concern (LOCs), identified during a SWMU assessment in 2013 (NASA 2013). Since the SWMU assessment, further confirmatory sampling and assessment was conducted for each LOC, and based on the data collected during these assessments, it was determined that Resource Conservation and Recovery Act Facility Investigation to further evaluate soil and groundwater was to be conducted at two LOCs: LOC 1 – Former Underground Storage Tanks (groundwater) and LOC 3 – Radar Antenna Refurbishment Area (soil). The LOC 1 groundwater assessment is ongoing, and the results will be presented under a separate cover. It was also determined that soil IM would be completed at two of the LOCs, LOC 3 and LOC 10 – Compressor Building Condensate Discharge. A Soil IM Work Plan was prepared and submitted in October 2021 (NASA 2021). The plan proposed excavation and disposal of barium and copper impacted soil in the LOC 3 and 10 areas. This report presents a summary and results of the soil IM implementation activities conducted at LOCs 3 and 10. The site contaminates of concern for this soil IM are barium and copper. The activities presented in this report includes soil IM implementation and groundwater sampling. From January 23 through March 24, 2023, AECOM Technical Services, Inc. (AECOM) field personnel conducted IM implementation activities in the LOC 3 and 10 areas. As presented in the IM Work Plan, shallow soils, impacted with metals, were excavated to a depth of 2 feet below land surface in the central area of the site around the radar antenna and associated equipment. AECOM personnel excavated 77.43 tons of soil using hand tools and, when able, heavy equipment. The soils were placed into lined roll-off containers, which were covered and transported under manifest to the Cedar Trail Landfill in Bartow, Florida. The site was restored to original condition using certified clean backfill material (sand), with filter fabric, and gravel. Areas outside of the excavation were restored with grass seed. On June 6, 2023, AECOM field personnel conducted groundwater sampling activities within the soil IM excavation area. AECOM personnel collected one groundwater sample from monitoring well Q6RS-MW0003. The sample was submitted to a fixed-based laboratory for analysis by United States Environmental Protection Agency Method 6020B for metals (barium and copper). Barium and copper were detected at 18 micrograms per liter (µg/L) and 14 µg/L, respectively, and were below the State of Florida Groundwater Cleanup Target Levels (GCTLs) for barium at 2,000 µg/L and copper at 1,000 µg/L.

Chadwick Sloan Lee↗
NASA NTRS1992

On the placement of active members in adaptive truss structures for vibration control

The problem of optimal placement of active members which are used for vibration control in adaptive truss structures is investigated. The control scheme is based on the method of eigenvalue assignment as a means of shaping the transient response of the controlled adaptive structures, and the minimization of required control action is considered as the optimization criterion. To this end, a performance index which measures the control strokes of active members is formulated in an efficient way. In order to reduce the computation burden, particularly for the case where the locations of active members have to be selected from a large set of available sites, several heuristic searching schemes are proposed for obtaining the near-optimal locations. The proposed schemes significantly reduce the computational complexity of placing multiple active members to the order of that when a single active member is placed.

Lu, L.-Y.↗
NASA NTRS2016

Human Mars Landing Site and Impacts on Mars Surface Operations

NASA has begun a process to identify and discuss candidate locations where humans could land, live and work on the Martian surface. These locations are referred to as Exploration Zones (EZs). Given current mission concepts, an EZ is a collection of Regions of Interest (ROIs) that are located within approximately 100 kilometers of a centralized landing site. ROIs are areas that are relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains a landing site and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. These candidate EZs will be used by NASA as part of a multi‐year process of determining where and how humans could explore Mars. In the near term this process includes: (a) identifying locations that would maximize the potential science return from future human exploration missions, (b) identifying locations with the potential for resources required to support humans, (c) developing concepts and engineering systems needed by future human crews to conduct operations within an EZ, and (d) identifying key characteristics of the proposed candidate EZs that cannot be evaluated using existing data sets, thus helping to define precursor measurements needed in advance of human missions. Existing and future robotic spacecraft will be tasked to gather data from specific Mars surface sites within the representative EZs to support these NASA activities. The proposed paper will describe NASA's initial steps for identifying and evaluating candidate EZs and ROIs. This includes plans for the "First Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars" to be held in October 2015 at which proposals for EZs and ROIs will be presented and discussed. It will also include a discussion of how these considerations are (or will be) taken into account as future robotic Mars missions are defined and developed. One or more representative EZs, drawn from similar previous studies involving Mars sites, will be used in the proposed paper to illustrate the process NASA envisions for gathering additional data from robotic precursor missions to assist in making a final selection of an EZ for human crews as well as the steps likely to occur during the buildup of a habitation site. Examples of the systems and operations likely to be used by human crews, assisted by robotic vehicles, to explore the scientific ROIs as well as developing the resource ROIs within the example EZs will be discussed.

Bussey, Ben↗
NASA NTRS2016

Mars Surface System Common Capabilities and Challenges for Human Missions

NASA has begun a process to identify and evaluate candidate locations where humans could land, live and work on the martian surface. These locations are referred to as Exploration Zones (EZs). Given current mission concepts, an EZ is a collection of Regions of Interest (ROIs) that are located within approximately 100 kilometers of a centralized landing site. ROIs are areas that are relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains a landing site and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. In parallel with this process, NASA continues to make progress on the Evolvable Mars Campaign examining alternatives that can pioneer an extended human presence on Mars that is Earth independent. This involves ongoing assessments of surface systems and operations to enable a permanent, sustainable human presence. Because of the difficulty in getting equipment and supplies to the surface of Mars, part of these assessments involve identifying those systems and processes that can perform in multiple, sometimes completely unrelated, situations. These assessments have been performed in a very generic surface mission carried out at a very generic surface location. As specific candidate EZs are identified it becomes important to evaluate the current suite of surface systems and operations as they are likely to perform for the specific locations and for the types of operations - both scientific and development - that are proposed for these EZs. It is also important to evaluate the proposed EZs for their suitability to be explored or developed given the range of capabilities and constraints for the types of surface systems and operations being considered within the EMC. This means looking at setting up and operating a field station at a central location within the EZ as well as traversing to and exploring the scientific ROIs within the boundaries of the EZ. The proposed paper will describe the current status of common systems and operations as they can be applied to actual EZ locations on Mars. Initially these EZs will be the four locations identified MEPAG's Human Exploration of Mars Science Analysis Group (HEM‐SAG) that will be used as representative of the EZs that will emerge from the process that NASA has initiated. An example process that could be commonly applied is an approach for developing a field station site plan that would be demonstrated by applying this process to each of the four HEM‐SAG sites. Examples of common systems include (a) mobility systems that can be used to off‐load and move payloads to specific locations at the central field station location that could also be used to traverse long distances to reach some of the more remote ROIs or (b) robotic systems that can support various activities (such as system set up and maintenance) at the field station that could also be used to explore scientific ROIs and used to support site‐specific ISRU production activities.

Hoffman, Stephen J.↗
NASA NTRS2017

Access NASA Satellite Global Precipitation Data Visualization on YouTube

Since the satellite era began, NASA has collected a large volume of Earth science observations for research and applications around the world. The collected and archived satellite data at 12 NASA data centers can also be used for STEM education and activities such as disaster events, climate change, etc. However, accessing satellite data can be a daunting task for non-professional users such as teachers and students because of unfamiliarity of terminology, disciplines, data formats, data structures, computing resources, processing software, programming languages, etc. Over the years, many efforts including tools, training classes, and tutorials have been developed to improve satellite data access for users, but barriers still exist for non-professionals. In this presentation, we will present our latest activity that uses a very popular online video sharing Web site, YouTube (https://www.youtube.com/), for accessing visualizations of our global precipitation datasets at the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC). With YouTube, users can access and visualize a large volume of satellite data without the necessity to learn new software or download data. The dataset in this activity is a one-month animation for the GPM (Global Precipitation Measurement) Integrated Multi-satellite Retrievals for GPM (IMERG). IMERG provides precipitation on a near-global (60 deg. N-S) coverage at half-hourly time interval, providing more details on precipitation processes and development compared to the 3-hourly TRMM (Tropical Rainfall Measuring Mission) Multisatellite Precipitation Analysis (TMPA, 3B42) product. When the retro-processing of IMERG during the TRMM era is finished in 2018, the entire video will contain more than 330,000 files and will last ~3.6 hours. Future plans include development of flyover videos for orbital data for an entire satellite mission or project. All videos, including the one-month animation, will be uploaded and available at the GES DISC site on YouTube (https://www.youtube.com/user/NASAGESDISC).

precipitation↗
NASA NTRS1985

Spectral Characterization of Suspected Acid Deposition Damage in Red Spruce (picea Rubens) Stands from Vermont

In an attempt to demonstrate the utility of remote sensing systems to monitor sites of suspected acid rain deposition damage, intensive field activities, coupled with aircraft overflights, were centered on red spruce stands in Vermont during August and September of 1984. Remote sensing data were acquired using the Airborne Imaging Spectrometer, Thematic Mapper Simulator, Barnes Model 12 to 1000 Modular Multiband Radiometer and Spectron Engineering Spectrometer (the former two flown on the NASA C-130; the latter two on A Bell UH-1B Iroquois Helicopter). Field spectral data were acquired during the week of the August overflights using a high spectral resolution spectrometer and two broad-band radiometers. Preliminary analyses of these data indicate a number of spectral differences in vegetation between high and low damage sites. Some of these differences are subtle, and are observable only with high spectral resolution sensors; others are less subtle and are observable using broad-band sensors.

Vogelmann, J. E.↗