Open data for astrophotography.
Catalogs, annotation, metadata, and publishing tools for people who would rather understand the sky than fight the software.
What is Étendue?
Étendue is an open framework for astronomical catalogs, annotation, metadata, and publishing. Rather than a single application, it is a collection of interoperable projects built around a common data model. Each component can stand alone while sharing the same underlying information.
Principles
Open
Favor open formats, documented schemas, and permissive licensing whenever practical.
Accurate
Generate catalogs from authoritative sources with transparent provenance rather than maintaining them manually.
Composable
Small tools should work independently while becoming more powerful together.
Projects
Catalogs
Modern astronomical catalogs generated from public data for annotation, analysis, and publication.
Annotation
Fast browser-based rendering with WCS support and extensible annotation layers.
Metadata
A common schema describing astronomical images, observations, equipment, and derived products.
Publishing
Static websites, APIs, galleries, and exports built from the same underlying metadata.
In Progress
- Modern regenerated NGC/IC catalog
- Reflection nebula catalogs
- Dark nebula catalogs
- Browser annotation engine
- etendue.yaml metadata specification
- Developer documentation