2026 SAG Award Winners
Alaska Satellite Facility (ASF)
Project Goal
The mission of the Alaska Satellite Facility (ASF) is Making Remote-Sensing Data Accessible.We serve NASA’s collection of Synthetic Aperture Radar (SAR) data to the public as part of NASA’s Earth Science Data Systems Program, and strive to make the SAR datasets we archive accessible to a wide range of users.
Historically, significant processing and expertise were required to leverage SAR data, limiting its use to a relatively small community of experts. As more SAR data was made available to the public, the wider geospatial community became increasingly interested in learning how to use SAR for a range of applications.
ASF supports the GIS community by providing access to analysis-ready SAR products in GIS-friendly data formats, developing tools and services that make it easier to use SAR data in GIS workflows, and publishing guidance and interactive tutorials demonstrating how to use SAR datasets in GIS software environments.
Learn more about us
Learn more about our application: Site 1 | Site 2
Business Problem Solved
Until recently, most available SAR datasets required additional processing, such as Radiometric Terrain Correction (RTC), to make them suitable for use in GIS workflows. RTC corrects for distortions caused by the side-looking geometry of SAR acquisitions, resulting in imagery that aligns with other geospatial datasets.
In 2020, ASF introduced the cloud-native HyP3 on-demand processing platform to provide analysis-ready SAR datasets, including RTC, to the public. The Sentinel-1 RTC (RTC-S1) products generated by the OPERA project at JPL are now also available from ASF, offering easy access to a decade of Sentinel-1 RTC imagery. The recently launched NISAR mission generates analysis-ready products suitable for use in GIS.
With increased availability of analysis-ready SAR products, the focus of ASF’s efforts to provide guidance and services to GIS users has been shifting from generating RTC products to efficiently accessing and working with available RTC products.
Technology Implemented
ASF leverages ArcGIS StoryMaps to publish interactive tutorials providing guidance on accessing and using SAR data. ASF’s StoryMap tutorials are featured on the ASF ArcGIS Online homepage, linked to from other documentation, and embedded in other websites.
ASF maintains image services for OPERA RTC-S1 products in NASA’s Earthdata GIS (EGIS) ArcGIS Enterprise environment, allowing users to explore millions of RTC products interactively without having to download the data first. We also host image services for disaster response efforts in support of the NASA Earth Science Applied Sciences Disasters Program.
ASF’s ArcGIS Python Toolbox provides custom SAR processing scripts in the familiar ArcGIS geoprocessing tool format. The custom tools support common RTC-based workflows, including SAR scale conversion, surface water extent mapping, change detection using a log difference calculation, and generating false-color RGB images from data collected in two different polarizations.
Development Team Biography
All ASF staff contribute to making SAR data accessible.
Refer to our GitHub repositories for development personnel:
On Demand: https://github.com/ASFHyP3/hyp3/graphs/contributor
ArcGIS Toolbox: https://github.com/ASFHyP3/asf-tools/graphs/contributors
Image Services: https://github.com/ASFHyP3/gis-services/graphs/contributors
Vertex: https://github.com/asfadmin/Discovery-SearchUI/graphs/contributors
On Demand Documentation: https://github.com/ASFHyP3/hyp3-docs/graphs/contributors
NISAR Data User Guide: https://github.com/ua-asf/nisar-docs/graphs/contributors
Significant contributions to GIS support efforts:
Heidi Kristenson, Senior GIS Specialist
- Primary publisher/administrator of StoryMaps, Web Maps, Web Apps, Image Services
- Primary developer of the ArcGIS Python Toolbox
Andrew Johnston, Principal Engineer
- AWS architect for Image Server deployments
- Primary developer of image service update scripts
Jacquelyn Smale, Software Engineer
- Image Server suppo