STAC
SpatioTemporal Asset Catalog. An open specification for describing geospatial datasets to make them searchable and discoverable. Provides a standard way to catalog satellite imagery, derived products, and other spatiotemporal data using Items, Collections, and Catalogs.
Overview
The SpatioTemporal Asset Catalog (STAC) is a specification for describing and cataloging geospatial data assets. Born from frustration with incompatible satellite data portals, STAC creates a unified way to index, discover, and access EO data. Adopted by Microsoft Planetary Computer, AWS Earth Search, and Element 84.
How It Works
Three core objects: STAC Items (GeoJSON Features with spatiotemporal metadata linking to data files), Collections (groups of related Items with dataset-level metadata), and Catalogs (top-level entry points). Static catalogs can be hosted as JSON files on any web server. The STAC API adds search endpoints with spatial, temporal, and property-based filtering.
Key Facts
- Version 1.0.0 released June 2021, adopted as OGC Community Standard.
- Items are valid GeoJSON Features — compatible with existing tools.
- Static catalogs need no server — just JSON files on any web host.
- Works hand-in-hand with COG for serverless data access.
Applications
Cloud-Native Data Discovery
Searching petabyte-scale satellite archives using standardized queries.
Automated Pipelines
Discovering new acquisitions and feeding them into processing workflows.
Multi-Source Integration
Combining data from different providers through a common interface.
Limitations & Considerations
Flexibility can lead to inconsistent implementations. Static catalogs become unwieldy with millions of items. The API requires server infrastructure. Extension proliferation requires client-side handling.
History & Background
Emerged from a 2017 Radiant Earth sprint. Drafted by Element 84, Development Seed, Planet, and others. V1.0.0 released June 2021. Recognized as OGC Community Standard in 2025.
Related Terms
Analyze STAC data with LYRASENSE
Use our agentic notebook environment to work with satellite data and compute indices like STAC — no setup required.