Data sources
Parallax is built entirely on open data. Here is every source, what we use it for, and its licence.
Sources and licences
| Source | Used for | Licence and credit |
|---|---|---|
| European Ground Motion Service (EGMS) | Ground movement measurements from Sentinel-1 radar, Level 3 Ortho (vertical), release 2020–2024 | Copernicus data policy: full, free and open access. Generated using European Union's Copernicus Land Monitoring Service information. Processed by Parallax; not endorsed by the European Union. |
| Copernicus Sentinel-1 | The radar satellites that collect the measurements | Copernicus Sentinel data licence. Contains modified Copernicus Sentinel data (2020–2024). |
| postcodes.io | Postcode locations and local authority names | Open Government Licence v3.0. Contains OS data © Crown copyright and database right. Contains Royal Mail data © Royal Mail copyright and database right. Source: Office for National Statistics. |
| OpenStreetMap via OpenFreeMap | Street map background in reports | Open Database Licence (ODbL). © OpenStreetMap contributors. Map tiles by OpenFreeMap, © OpenMapTiles. |
| CelesTrak | Published orbital elements for the live satellite positions and pass times | Public orbital data. Orbital elements from CelesTrak (celestrak.org). |
| Natural Earth | Land outlines for the globe | Public domain. Made with Natural Earth. |
| OS Code-Point Open | Postcode centres in Great Britain: which squares are near homes, and postcodes for Moving Britain | Open Government Licence v3.0. Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. |
| ONS Local Authority District boundaries (May 2026) | Area pages and area statistics | Open Government Licence v3.0. Source: Office for National Statistics licensed under the Open Government Licence v3.0. Contains OS data © Crown copyright and database right 2026. |
| Mining Remediation Authority: Development High and Low Risk Areas | Coal mining context in reports and the professional tool | Open Government Licence v3.0. Contains public sector information licensed under the Open Government Licence v3.0, from the Mining Remediation Authority. |
How often it updates
EGMS publishes a new release about once a year, each adding the latest year of measurements. We rebuild the whole UK dataset when a new release appears; the release in use is shown on every result and report. Satellite positions update every few hours from CelesTrak.
What we add
We don’t change the underlying measurements. We compare each square with its surroundings, fit a physical model with honest uncertainty, and turn the result into plain English. Every report lists the exact EGMS point and release it came from.