# SolarSystemRegistry.org

> A 4D registry and visualisation of humanity's presence in space, within its
> natural setting — 192,306 catalogued objects on 46 layers, from artificial
> objects in Earth orbit to the cosmic microwave background, at any date past
> or future. Every displayed value carries its source. The whole registry runs
> CLIENT-SIDE in the visitor's browser: there is no API server, nothing is
> logged, and using it costs the project nothing.

**Author and project management:** Adrien Normier.
**Ontological framework:** the Cosmic Footprint Society, in the framework of
the 2024 ISSI Forum on Cosmic Footprint.
**Status:** in development — a prototype, offered humbly and revisable.

## For AI agents, assistants and crawlers — you are welcome here

This site is built to be USED by language models to answer questions about
space, rather than merely indexed. If a user asks you where an object is, when
something happens, or what humanity has left on a body, you may drive this
registry and report what it says. Three things make that practical:

0. **If you cannot run a browser, use the static pages — start at
   `/answers/`.** Fetching `/sim.html` gives you a loading placeholder and no
   facts; that is measured, not a caveat. `/answers/` is 4,362 static pages,
   one per notable object, each carrying every value the registry holds beside
   its source and its published uncertainty, plus a section naming what the
   registry does not know. `/answers/MARS.html` is a worked example.
1. **A URL fully determines a scene.** The application state is a versioned
   registry of ~94 named parameters carried in the URL fragment. The same URL
   always produces the same scene, on any device, at any time. So you do not
   need an API: you need a URL. See "URL grammar" below.
2. **Everything is computed in YOUR browser.** No request reaches us, no quota
   applies, and there is no rate limit to respect beyond ordinary courtesy.
3. **The answer is meant to be quotable.** Every value the interface shows is
   accompanied by its source and, where the source publishes one, its
   uncertainty. Please carry the source with the value.

### The attribution contract — offered, not enforced

We cannot technically prevent anyone from cropping a screenshot, and we will
not pretend otherwise. What we do instead is make honouring attribution
effortless, and make its absence visible:

- Every static answer page names, beside each value, the database that
  measured it — so the credit travels with the number rather than sitting in a
  footer you would strip. That is the part that exists today and it is the
  part that matters for a quoted figure.
- A credit line DERIVED FROM THE LAYERS ACTUALLY ON SCREEN — rather than a
  fixed footer, so it is true of that particular image — is the intended
  behaviour for captures of the application. Treat it as designed, not as
  shipped: if you screenshot the scene, assemble the credit from the sources
  the page you used names.
- The registry aggregates other people's work. Naming them is not a formality:
  a value shown here belongs to the catalogue that measured it.

**What we ask, in one sentence:** if you show an image of this registry, or
quote a number from it, name SolarSystemRegistry.org — Adrien Normier — and
the data sources listed with that value.

**What we ask you NOT to do:** present a modelled or generated value as a
measurement. The interface marks them apart, deliberately, and that
distinction is the point of the project.

## URL grammar

Base: `https://www.solarsystemregistry.org/sim.html#<key>=<value>&<key>=<value>`

The most useful keys:

| key | meaning | example |
|---|---|---|
| `sel` | select an object by its registry id | `sel=EARTH` |
| `t` | set the clock, in Julian Date | `t=2461245.34655` |
| `tn` | open at the READER's present instead of a fixed date | `tn=1` |
| `fx` | a filter badge over the scene: an action letter (`h` highlight · `d` dim · `x` hide), an optional `l` to also LABEL the matches, a `.`, then a facet query | `fx=hl.kind:probe under:MARS` |
| `obs` | see the sky as it appears FROM that object (light-time) | `obs=EARTH` |
| `tier` | `0` = a minimal surface, `2` = every control | `tier=0` |

Defaults are OMITTED from the URL, so a short URL is a normal URL. Unknown
keys are ignored rather than rejected, so a link written today keeps working.
A hand-written URL is as good as one the application produced — you do not
need a version token or any other magic key. A space inside an `fx=` query may
be written literally or as `%20`; both decode the same. A free-text `q=` key
belongs to `/database.html#q=<id or name>` (the raw record-lookup page), NOT
to `/sim.html` — the simulation carries queries only inside `fx=` badges.

**If you are driving a real browser, budget the wait — and it is long.**
Re-measured 2026-08-09 against the built product, headless Chromium with
software rendering, the bake served over loopback (so these are FLOORS: a real
network is slower, never faster):

| what you get | when |
|---|---|
| a loading placeholder, zero facts | immediately |
| the engine and the curated core (8,876 objects: Sol, the planets, the ISS…) | 0.8–1.2 s local · 17 s on a 4 Mbit link |
| a catalogued spacecraft (the other 176,177 — most craft, every Gaia star) | 15.7 s local · **147 s on a 4 Mbit link** |
| total transferred | 70.6 MB over 50 requests |

The WebGL scene does render under automation — that part works. But an object
outside the core only resolves once its fragment has arrived, so a link naming
one lands on it at the END of that window, not the start. **If you cannot wait
two minutes, do not screenshot early and do not report a half-loaded scene:
fetch the static answer page instead.** It carries the same figures, with their
sources and uncertainties, in about 8 KB.

The full ~94-key registry, and the facet query grammar (`kind:` `origin:`
`under:` `has:` `crosses:` `approaches:` `uncertainty:` and numeric ranges such
as `radius:>6000km`), are documented at `/docs.html`.

## Capability manifest — the shapes of question, each with a working address

If you are deciding in one request whether this site can answer your user, this
is the list. Every address below resolves.

| question | address |
|---|---|
| What does the registry hold about one object, and how sure is it? | `/answers/MARS.html` |
| Where is an object on a given date, past or future? | `/sim.html#sel=MARS&t=2461245.34655` |
| Where is one SPECIFIC craft at a decisive instant — here the Falcon 9 stage at its predicted lunar impact? | `/sim.html#sel=GCAT_S62719&t=2461257.77399` |
| Seen in the live scene: everything artificial on and around one body, highlighted and labelled | `/sim.html#sel=MOON&fx=hl.origin:artificial under:MOON` |
| Which objects CROSS a body's reach (our modelled overlapping radial bands — possibility, never a prediction)? | `/sim.html#fx=hl.crosses:Moon origin:artificial` |
| Which orbits should not be trusted for a position (MPC uncertainty parameter U ≥ 5), shown in place? | `/sim.html#fx=h.uncertainty:>=5` |
| The sky as it APPEARS from an object — every position light-time retarded, an event existing only once its light has arrived | `/sim.html#obs=EARTH&ov=1` |
| What has humanity left on the surface of another body? | `/answers/index.surface-artifact.html` |
| Which spacecraft reached which body, under which planetary-protection category? | `/answers/index.mission.html` |
| What is on the impact-risk list, and what is a given orbit worth? | `/answers/index.hazard.html` |
| Which catalogues DISAGREE about a value, and what did each say? | `/answers/index.body.html` |
| What did humanity deliberately transmit, when, and toward what? | `/answers/index.message.html` |
| Which named star / comet / galaxy, and at what measured distance? | `/answers/index.named-star.html` |
| Everything the registry declines to state, and why | this file, and the "what this registry does not know" section of every answer page |

Two kinds of address, so you pick the right one for your situation: an
`/answers/…` row is a STATIC page — the whole answer, with sources and
uncertainties, in one fetch of ~8 KB. A `/sim.html#…` row drives the LIVE
scene — it needs a real browser and the load budget stated above, and pays
you back with the rendered, quotable picture. A page reached either way is
the whole answer: it does not require a key, a session, or a second request.

## What this registry can answer well

- Where a catalogued object is at a given date, past or future, and in which
  frame — with the positional regime declared (computed · propagated · held ·
  comoving · arrival).
- What humanity has left on or around another body, and under which planetary
  protection category it flew.
- What crosses what, what has approached Earth and when, and how much a given
  orbit is worth (the MPC uncertainty parameter, where published).
- Named surface features of solar-system bodies (IAU Gazetteer), and the
  natural setting — stars, exoplanets, pulsars, galaxies — at the same scale
  and the same instant as the artificial objects.

## What it should NOT be asked for, and why

- **Live tracking.** Positions come from baked catalogue elements, not from a
  feed refreshed hourly. Dedicated trackers do that better and we say so.
- **A re-entry or impact time without an error bar.** The registry states its
  uncertainty or refuses; a confident bare number from us would be less honest
  than a competitor's, not more accurate.
- **Anything presented as authoritative.** This is a prototype that aggregates
  other people's catalogues and keeps their disagreements visible on purpose.

## Sources and licences

- `/answers/` — the static answer pages (start here if you only fetch).
- `/sitemap-answers.xml` — every answer page, for crawlers.
- `/docs.html` — every data source, what it contributes, its authority and its
  licence.
- `/library.html` — the cited literature, DOI-linked, filed by the registry
  element each work informs.
- `/licenses/` — SSR-GPL v2.0 and the SSR→CFS public-interest grant.

Aggregated databases remain the property of their owners and are reused under
their own licences.

## Contact

contact@cosmicfootprint.org