Worldview is a software tool designed for interactively browsing and downloading imagery from NASA’s Earth observing satellites. Building upon a set of open source mapping and user interface libraries, it provides an environment to visually discover interesting phenomena as observed by NASA satellites, then download the data for further analysis. It was originally designed to address the needs of the near-real-time applications community to provide relevant information for time-critical scenarios such as wildfire and flood management. As such, satellite imagery is available to be viewed in Worldview within four hours of observation; the imagery can be viewed in its highest, or native, resolution, and the imagery can be panned and zoomed rapidly through space and time to find the most relevant/cloud-free information available.
Due to the vast amount of satellite imagery acquired and stored by NASA, it is inherently difficult to provide a user interface capable of quickly browsing this archive to find phenomena of interest. In the past, it was difficult to serve satellite imagery fast enough for a large number of users to interactively browse it due to the computational overhead of retrieving, processing, and transmitting the imagery back to the user. The Worldview Web application was designed to provide an interface to interactively browse NASA satellite imagery for visualization and discovery. It can be used in a Web browser on a desktop computer or mobile device (see figure).
The goal is to find imagery and then use it within the application, download and share it, or download the underlying data granules that were used to generate the imagery and subsequently perform further analysis using it. Worldview has been carefully designed to provide as simple and powerful a user interface as possible to achieve its goals. Its back end primarily consists of the openly accessible NASA Global Imagery Browse Service (GIBS) that rapidly provides imagery to Worldview. Worldview itself is comprised of a significant number of open source libraries that have aided in its rapid development and success. Primary open source components are the OpenLayers mapping library, the Proj4js coordinate transformation library, and the jQuery general-purpose library.
When a user visits https://earthdata.nasa.gov/worldview, they are presented with an interface similar to Google Maps that lets them pan and zoom through satellite imagery. The user can select from a number of satellite products, change the selected date, download the imagery, or download the underlying data that created the imagery. The user can also share a “permalink” of the current view with other users or view the imagery from an Arctic/Antarctic polar stereographic perspective.
This work was done by Ryan Boller, Kevin Murphy, and Elizabeth Timmons of Goddard Space Flight Center; John McGann, Taylor Gunnoe, Matthew Cechini, and Tilak Joshi of Columbus Technologies and Services, Inc.; and Shriram Havajhala and Jeffrey Schmaltz of Sigma Space Corporation. GSC-17111-1