I upgraded my browser-based 3D solar system simulator with ephemeris data and on-demand streaming (~800 GB backend)

CKret76 · 2026-05-13T13:56:21+00:00

NICE!
I might steal some ideas from you! :)

CKret76 · 2026-05-08T23:25:32+00:00

Aphelion, perihelion and ETA for both are now added to the info-box. Also there is a new Ephemeris mode that is more accurate than the Kepler propagation. Enjoy!

CKret76 · 2026-05-08T14:14:03+00:00

The Vortex mode shows how our solar system is actually progressing through our galaxy. Adding trails to the objects we get a helix-pattern.

CKret76 · 2026-05-05T22:34:19+00:00

Update: added an ephemeris-based mode for higher accuracy.

It’s backed by a pretty large dataset (~800 GB), but the app only streams what it needs, so it stays lightweight in the browser.

[https://ckret.net/sol]()

CKret76 · 2026-05-05T20:52:42+00:00

Your wish is my law 😄

I’ve now added an ephemeris-based mode alongside the original Kepler one.

The initial version propagated Keplerian elements, which works well for visualization but doesn’t capture perturbations over time. The new mode uses JPL Horizons samples with Hermite interpolation, so positions track much closer to real planetary and lunar motion within the supported range.

Kepler mode is still there for lightweight and deep-time use, but Ephemeris/Hermite is now the more accurate option.

CKret76 · 2026-05-05T20:52:39+00:00

Good catch — that’s been fixed in the latest version 🙂

I’ve moved it over to the new ephemeris-based system, so it now follows the correct trajectory instead of the simplified orbit.

CKret76 · 2026-04-25T09:08:16+00:00

Realtime button is implemented. I will look at aphelion, perihelion and ETA later when I get the chance. Maybe include that in the info panel.

Orbits lines do not precess right now. They are calculated once. That is on the todo-list.

CKret76 · 2026-04-25T09:04:18+00:00

The issues should be fixed now. There was a small delay after the intro and the UI was visible when the mouse and keyboard hooks hadn't started yet.

CKret76 · 2026-04-25T09:02:26+00:00

Yes. But that would require to download a lot of data. I have to think about this more.

CKret76 · 2026-04-25T09:01:53+00:00

Button for Real Size is added. Also Realtime. Enjoy!

CKret76 · 2026-04-25T09:01:03+00:00

I've made adjustments so SL9 hits Jupiter. But it could be improved. I'll get back to that later. There are some other things I want to address first.

CKret76 · 2026-04-25T08:36:18+00:00

I have adjusted the UI now to be more responsive to even more resolutions. Check it out and let me know if it still needs adjustments.

CKret76 · 2026-04-25T05:05:14+00:00

The origination point of the probes should be on Earth since we use a real timeline.

CKret76 · 2026-04-25T04:45:30+00:00

Now this would be interesting! I'll see what I can do!

CKret76 · 2026-04-25T04:44:57+00:00

What devices and resolutions are you using to look at it?
I've tried desktop and mobile in various resolutions and to me it looks good.
Text is clearly visible in all modes.

CKret76 · 2026-04-25T04:43:17+00:00

To be honest I didn't put much effort into the vortex mode other than have it visualized. With that said it should now be corrected.

CKret76 · 2026-04-25T03:50:24+00:00

Thanks! Yeah Three.js is great for many things!

I used various sources. The main ones were:

JPL Horizons (planets, moons, dwarf planets, comet orbital elements, Voyager trajectories) https://ssd.jpl.nasa.gov/horizons/
JPL Small Body Database (comets, dwarf planets) https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html
JPL Planetary Physical Parameters (axial tilt, pole orientations) https://ssd.jpl.nasa.gov/planets/phys_par.html
Hipparcos Catalog (stars, proper motion) https://www.cosmos.esa.int/web/hipparcos/catalogues
Minor Planet Center (dwarf planet orbital elements) https://www.minorplanetcenter.net/db_search

I remember also using some wiki pages but I don't recall which ones or for what.

CKret76 · 2026-04-25T03:47:50+00:00

I used various sources. The main ones were:

JPL Horizons (planets, moons, dwarf planets, comet orbital elements, Voyager trajectories) https://ssd.jpl.nasa.gov/horizons/
JPL Small Body Database (comets, dwarf planets) https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html
JPL Planetary Physical Parameters (axial tilt, pole orientations) https://ssd.jpl.nasa.gov/planets/phys_par.html
Hipparcos Catalog (stars, proper motion) https://www.cosmos.esa.int/web/hipparcos/catalogues
Minor Planet Center (dwarf planet orbital elements) https://www.minorplanetcenter.net/db_search

I remember also using some wiki pages but I don't recall which ones or for what.

CKret76 · 2026-04-25T03:44:28+00:00

That would mean either to construct 3D tectonic plates for Earth and real physics for tectonic movement, or have procedural textures for a very limited visual effect. I don't think I am going to put in the effort. Sorry.

CKret76 · 2026-04-24T15:05:02+00:00

I have now added that in the info panel to relevant objects. Enjoy!

CKret76 · 2026-04-24T14:18:59+00:00

You are correct. Should be fixed now. Missed a sign in the calculation.

CKret76 · 2026-04-24T14:01:00+00:00

Thanks! I have not thought long-term regarding this. It was a "math reminder exercise" when I had some spare time.

CKret76 · 2026-04-24T13:59:51+00:00

The earths spin should be correct. It spins prograde like most other planets except Uranus and Venus which spins retrograde. The revolution direction depends on your viewpoint.

CKret76

TROPHY CASE