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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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Amazonia Disasters: Assessing Methods for Gold Mining-Related Deforestation Detection in Amazonia Using NASA Earth Observations

Artisanal and small-scale gold mining (ASGM) is responsible for a large fraction of deforestation and disturbance in Amazonia. These activities cause severe impacts on the rainforest ecosystem and socioeconomic state of the region. NASA DEVELOP partnered with the Asociación para la Conservación de la Cuenca Amazónica (ACCA), NASA SERVIR Science Coordination Office, and the Spatial Informatics Group to enhance ASGM-related deforestation detection methods. ACCA currently uses the Omnibus Q-test Change Point Detection Algorithm to identify changes in Synthetic Aperture Radar (SAR) monthly-aggregated temporal data from the Sentinel-1 satellite. The team determined the algorithm's accuracy by comparing a stratified random sample of change points against data from January 2019 to June 2020 identified using PlanetScope and Landsat 8 Operational Land Imager (OLI) Earth observations through Collect Earth Online. Our results indicated a users' accuracy of 55% for temporal change detection and producer's and user's accuracies of 99% and 97%, respectively, for detecting when change did not occur. Of the labeled change points, only 19% were due to mining activity. This research can help our partners have a more accurate understanding of where illegal gold mining may be taking place and inform decisions to remediate this activity.

DEVELOP Tech Paper↗

Summary of the 5th GWIS & GOFC-GOLD Fire Implementation Team Meeting

The 5th joint Global Wildfire Information System (GWIS) and Global Observation of Forest and Land Use Dynamics (GOFC-GOLD) – Fire Mapping and Monitoring Implementation Team (FireIT) was held on 21-23rd June 2022, at Stresa, Italy. Thirty researchers from academia, government, and non-government organizations participated in the meeting, the majority in person (Figure 1) and several online. The meeting’s goals were to review recent progress made by the GWIS and the GOFC Fire-IT, discuss recent developments in fire science and technology, and determine the prospects for satellite-based fire monitoring and science in the context of forest and natural resource management and other applications. The joint meeting was aimed to building collaboration and cooperation amongst the international fire remote sensing community. After a brief background on GWIS-GOFC-GOLD Fire-IT, this article summarizes the latest updates on the various fire thematic areas presented by the attendees. The full presentations are available at https://gofcgold.org/meetings/5th-gofc-gold-fire-it-and-global-wildfire-information-systemgwis

Fires↗

Preliminary Results, Analysis and Overview of Part -1 of the GOLD Experiment

The Ground/Orbiter Lasercomm Demonstration (GOLD) is an optical communications demonstration between Japanese Engineering Test Satellite (ETS-V1) and an optical ground transmitting and receiving station at the Table Mountain Facility in Wrightwood California. Laser transmissions to the satellite were performed approximately four hours every third night when the satellite was at above Table Mountain.

GOLD ETS-V1 Table Mountain Facility optical commun↗

Gold coatings for cube-corner retro-reflectors

We report on a comparative study of optical performance of gold films deposited by resistive and e-beam evaporation, including measurements of the scattering from the coated surfaces. The effects of oxygen bombardment and titanium under-layer on optical properties and adhesion were evaluated. The influence of surface preparation on the optical properties was examined also.

reflectors↗