ESA Image Archive
How ESA's imagery and science archives are organised.
Overview
ESA maintains separate public imagery channels and scientific data archives, with different access models and different licence terms. The distinction matters both for finding material and for using it lawfully.
- ESA's public imagery and its science archives are separate systems with different terms.
- The ESAC Science Data Centre is the principal home for ESA mission science data.
- Gaia's data releases are among the most widely used astronomical datasets in existence.
- Joint-mission material may be distributed by more than one agency under different terms.
Two distinct systems
ESA's public-facing imagery channels distribute release pictures, mission photography and visualisations for general use, generally under Creative Commons Attribution–ShareAlike terms. This is where most people encounter ESA imagery.
Its science archives are a separate matter. The ESAC Science Data Centre hosts calibrated data from ESA missions for research use, organised by mission and instrument, with access models and terms set per mission. The two systems answer different questions and should not be assumed to share licensing.
The datasets that matter most
- Gaia's astrometric data releases — positions, parallaxes and proper motions for over a billion stars — underpin a very large share of contemporary stellar and Galactic astronomy.
- Planck's full-sky microwave background maps remain a primary cosmological dataset.
- Rosetta's comet 67P observations constitute the most detailed dataset ever obtained for a comet.
- Mars Express, Venus Express and BepiColombo hold long-baseline planetary observation records.
- XMM-Newton's X-ray archive is one of the principal high-energy astronomical datasets.
Joint missions complicate provenance
Hubble and JWST are operated as international partnerships, and their data and imagery are distributed through both American and European channels. The same observation may therefore be obtainable from more than one archive, potentially under different stated terms and with differently formatted credit lines.
For provenance purposes this means naming the archive an item actually came from, not the agency that seems most associated with the mission. The platform's records identify the specific source, which is the only way the licence claim can be checked.
Why Gaia is the outlier
Gaia deserves separate mention because of its effect on everything downstream. By measuring parallaxes for over a billion stars, it superseded the previous distance foundation — Hipparcos, with about a hundred thousand — exceeding it by four orders of magnitude in scale and substantially in precision.
Distance underpins luminosity, and luminosity underpins mass and age, so a large fraction of stellar parameters published since Gaia's releases ultimately depend on its measurements. Several of the stellar catalogues on this platform carry Gaia-derived values with that provenance recorded.
Continue in the data
Catalogues, hubs, and reference pages that hold the underlying records for this topic.
Frequently asked
- Where does ESA publish its mission data?
- Principally through the ESAC Science Data Centre, which hosts calibrated data from ESA missions organised by mission and instrument, with terms set per mission. That is separate from ESA's public imagery channels, which distribute release pictures and visualisations generally under Creative Commons Attribution–ShareAlike terms.
- Why is Gaia data so widely used?
- Because it supplies the distance foundation for stellar astronomy. Gaia measured parallaxes for over a billion stars, against roughly a hundred thousand from its predecessor Hipparcos, and with substantially better precision. Since distance underpins luminosity, and luminosity underpins mass and age, a large share of published stellar parameters now depend on it.
- Can the same image come from both NASA and ESA archives?
- Yes, for jointly operated missions such as Hubble and JWST. The same observation may be distributed through both agencies' channels, potentially under different stated terms and with differently formatted credit lines. For provenance the archive an item actually came from must be named, not the agency most associated with the mission.