About the ASF DAAC

Antarctica's Lambert Glacier, © 1997 CSA.

The National Aeronautics and Space Administration (NASA) Earth Science Data and Information System (ESDIS) Project is a part of the Earth Science Projects Division under the Flight Projects Directorate at Goddard Space Flight Center. As key components of ESDIS, 12 interlinked Distributed Active Archive Centers (DAAC) are operated by a distributed network of independent facilities across the United States — including the NASA DAAC operated by the Alaska Satellite Facility (ASF).

The ASF DAAC specializes in synthetic aperture radar (SAR) data collection, processing, archiving, and distribution. These data are or have been, supplied by SAR sensors on many different spaceborne and airborne platforms, including:

User Working Group

The ASF DAAC has a User Working Group (UWG) of scientists from the fields of research that the DAAC serves.

A formal Charter has not been written for the UWG. The UWG operates under the following terms of reference.

  • Reviewing the progress and performance of the DAAC relative to the ASF DAAC’s missions;
  • Representing the user community in the development and operation of the ASF DAAC products and services;
  • Suggesting specific data products and services to NASA and the ASF DAAC;
  • Providing input to NASA and ASF on the ASF DAAC objectives, priorities, target user communities, implementation approaches, and
    other issues.

About ASF DAAC Data

The ASF DAAC has a large archive of synthetic aperture radar (SAR) data from a variety of sensors, available at no cost. Some of the SAR datasets in the ASF DAAC archive require a short NASA proposal for access. In accordance with the memoranda of understanding (MOU) between the relevant flight agencies (CSA, ESA, JAXA) and the U.S. State Department, the ASF DAAC does not distribute SAR data for commercial use. 

Sentinel-1, ALOS PALSAR and other SAR data are open access and immediately downloadable from ASF’s Vertex interface, or from the ASF website. ERS-1, ERS-2, JERS-1 and RADARSAT-1 datasets have been acquired in partnership with other nations’ space programs. Those datasets require data proposals or preconditions. In addition, some datasets have residency requirements.

Get SAR Data

Note: Newcomers to ASF DAAC data may want to refer to the Get Started page.

ASF Data Search: Vertex

ASF has developed and deployed a user interface to highlight the contents of the pre-processed ASF DAAC SAR datapool. Vertex is an intuitive user interface that facilitates the search for and visualization of ASF DAAC datapool assets, delivery of relevant metadata about those assets, and bulk delivery of those ASF data. Vertex is designed to familiarize users with SAR data without requiring any prior knowledge of SAR platforms, beam modes, or processing parameters.

Go to Vertex


ASF’s API is an application programming interface that enables command-line search and download.

Learn More