Docs
Four documents: how to ask this catalogue a question, how to take all of it, how every number in it was made, and what to cite once you have used one. The index below goes a level deeper than the four cards — it lists the sections inside them, grouped by what you are trying to do rather than by which document they live in.
One request at a time, from a browser, a script or an observing tool.
- Start hereThe first request, and the shape of every answer.
- EndpointsEvery route, its parameters and a worked example.
- Positions at a dateProper motion applied to an epoch you choose.
- Cross-matchYour list of coordinates against this catalogue.
- One target, one nightRise, transit and set for a place and a date.
- EventsWhen rather than where: the calendar as data.
- In your own toolsCone search for TOPCAT, Aladin and anything else IVOA.
- Errors and limitsWhat a failure looks like, and how often you may ask.
The files, what is in them, and how to be sure you got them intact.
- The filesWhat each one holds and how big it is.
- Check itTwo commands that prove the download is the file.
- Load itpandas, astropy, DuckDB and TOPCAT.
- The columnsEvery column, its unit and its meaning.
- The properties columnThe JSON keys inside it, by kind of object.
- What is not in itThe deliberate omissions, and why.
Where each value came from and what was done to it on the way.
- Three rulesWhat this catalogue will and will not publish.
- DistancesThe ladder, rung by rung, and which rung each row is on.
- CosmologyThe expansion rate and the model redshifts are converted with.
- Stellar parametersTemperatures, radii and luminosities, and their sources.
- PositionsThe frame, the equinox and the epoch.
- ChecksThe plausibility rules that hold rows back.
- UpstreamsEvery catalogue ingested, one paragraph each.
- Not hereWhat was left out on purpose.
What to point a paper at, and what the licences require of you.
What the catalogue covers, who built it, and how to follow it.
- What is inThe selection rules, and the cuts behind the count.
- Image creditsEvery photographer and every observatory credited.
- Surface mapsWhere the planetary and lunar textures came from.
- Chart dataThe catalogues behind the sky map's stars and figures.
- News and releasesThe feeds that announce a new release.
WHAT YOU ARE READING ABOUT
] DR1 · 2026-08-21The catalogue behind all four documents is live: its numbers move when an upstream refreshes. What does not move is a release — a frozen, versioned bundle of the whole thing — and that is what a paper should cite. DR1 is the current one.