SDX makes datasets purchased by CSDA available to current and future NASA-funded researchers. This new user-friendly tool allows researchers to explore and order catalogued small satellite data from multiple commercial vendors in one place. Researchers can search the catalogue of CSDA data and imagery by defining an area of interest and specifying the date and cloud cover constraints (in the case of imagery). More information on how to use the SDX can be found in the User Guide.
Spire and Planet Data
CSDA has catalogued Planet imagery and Spire Global Navigation Satellite Systems (GNSS) data in the SDX, which are hosted in the NASA cloud.
Spire Global’s constellation receives signals transmitted by multiple GNSS constellations, including the U.S. Navstar Global Positioning System (GPS).
As the signal between the GNSS satellite travels through the atmosphere it is refracted. Spire small satellites in low Earth orbit receive the refracted signal and measure the magnitude of refraction, which provides researchers with information on the temperature and water vapor content of different levels of the atmosphere. GNSS data can be retrieved from small satellites every few hours, as opposed to data from satellites that both send and receive signals, which may only make observations every few days.
Three principal investigators (PIs) for CSDA pilot projects used Spire GNSS data to study atmospheric dynamics. Reflected GNSS signals can also be used to study ocean wind speeds, soil moisture, and sea surface height. A PI for the CSDA pilot used reflected GNSS signals from Spire to get sea surface height measurements for ocean altimetry applications.
At the time of the initial purchase of Spire data by CSDA, there was no suitable location to host (or archive) and distribute Spire data. The SDX now provides such a place for data discovery and distribution. Spire data are available from November 2019 to present, with a 30-day latency.