3D Simulation Guide

The Interactive 3D Solar System Simulation is where all the theory comes together. You can explore, verify, and compare observations against other planetariums like Stellarium .

Launch the 3D Simulation → 

Getting Started

Mouse & Keyboard

Simulation Controls

Speed Presets

The “1 second equals” dropdown offers these options:

Interface Overview

The simulation interface has seven collapsible panels on the right side of the screen:

Key Features

Celestial Positions

Open “Celestial Positions” to see real-time values for all objects:

• RA (Right Ascension) — position along the celestial equator
• Dec (Declination) — angle above or below the celestial equator
• Distance — in AU (Astronomical Units)

Tip: Click any planet name in this panel to center the camera on that object. Each object also has a visibility checkbox to show or hide it.

Celestial Tools

Open “Celestial Tools” to enable:

• Zodiac wheel - see the 12 zodiac constellations
• Polar line - visualize Earth’s axial tilt
• Star names - identify stars by name
• Constellations - show constellation patterns

Live Predictions

Open “Predictions” to see astronomical values measured directly from the running simulation:

• Year lengths — tropical year (at each solstice and equinox), anomalistic year, sidereal year
• Obliquity — Earth’s current axial tilt
• Precession rate — how fast Earth’s axis is shifting, in arcseconds per year
• Precession period — how long one full precession cycle takes
• Eccentricity — how elliptical Earth’s orbit currently is

These values update in real time as the simulation runs. Pause the simulation to get a stable reading at any specific date.

Special Objects

The simulation includes two unique reference objects that are not found in conventional planetariums:

• EARTH-WOBBLE-CENTER (dark sphere) — the fixed point around which Earth’s spin axis slowly traces a circle. To see it in action: enable “Polar line” in Celestial Tools, set speed to “1000 years”, and press Run. The pole visibly circles this point over ~25,684 years.
• PERIHELION-OF-EARTH (white sphere) — marks where Earth makes its closest approach to the Sun. This point slowly drifts counter-clockwise, completing one full circuit in ~111,296 years.

Both objects can be toggled on/off in the “Perihelion Planets” panel.

Things to Try

1. Watch Earth’s Axial Precession

• Enable “Polar line” in Celestial Tools
• Set “1 second equals” to “1000 years”
• Press Run and watch the pole trace a circle over ~25,684 years

2. See the 1246 AD Alignment

• Set date to 1245-12-14
• Observe PERIHELION-OF-EARTH aligned with EARTH-WOBBLE-CENTER
• This marks the perihelion-solstice alignment (December solstice = perihelion)

3. View Moon’s Nodal Precession

• Zoom in on Earth and Moon
• Tilt to ecliptic level
• Set “1 second equals” to “1 year”
• Watch the Moon’s orbit precess over ~18.6 years

4. Trace Venus’s 5-Petal Pattern

• Open “Select objects to trace”
• Select only “Venus”
• Enable “Trace”
• Set “1 second equals” to “1 year”
• Run and watch the famous 5-petal pattern appear

5. View the Age of Aquarius

• Set date to 2048-03-21
• Enable “Zodiac” in Celestial Tools
• See the March equinox point crossing into the Aquarius sector of the zodiac wheel

Important Dates to Explore

How the Model Differs

Unlike conventional planetariums that use ellipse formulas, this simulation builds every orbit from circles rotating at constant speed. No planet ever speeds up or slows down — yet the combination of multiple circular motions produces the same elliptical paths and variable speeds observed in nature.

Two slow background motions are visible at high speed settings:

1. Earth’s axial precession — Earth’s spin axis traces a circle around EARTH-WOBBLE-CENTER over ~25,684 years
2. Perihelion drift — PERIHELION-OF-EARTH slowly orbits the Sun over ~111,296 years

Planetary orbital periods and distances follow Kepler’s Third Law (P² ∝ a³), and the resulting positions match recorded observations across thousands of years.

For the full technical explanation, see How It Works.

Verification

Compare simulation values with:

• Stellarium Web 
• JPL Horizons 
• Mars Opposition Dates 

The model matches planetary ephemerides, Mars oppositions, Venus/Mercury transits, Jupiter-Saturn conjunctions, and eclipse data.

Tips

• UTC Time: All times are in UTC. Use a time converter  for local time
• Performance: Large time speeds (1,000+ years) work best in a desktop browser
• Orbit traces: Open “Select objects to trace” in Celestial Tools to draw orbital paths as the simulation runs

Next Steps

• Analysis & Export - Generate reports, export data, and validate against IAU references
• Technical Details - Three.js implementation, calculation order, and configuration settings
• The Model - Understand the underlying theory
• Configuration - See specific parameter values