Presets
Key Formulas
Astronomical Unit
Light Travel Time
Kepler's Third Law
Orbital Speed
Parameters
1.0×
1.0×
0.55
All
Playback Rate
Planet Reference
Mercury — 0.39 AU, 0.38 R⊕, e=0.21
Venus — 0.72 AU, 0.95 R⊕
Earth — 1.00 AU, 1.00 R⊕
Mars — 1.52 AU, 0.53 R⊕
Jupiter — 5.20 AU, 11.2 R⊕
Saturn — 9.54 AU, 9.45 R⊕, rings
Uranus — 19.2 AU, 4.01 R⊕
Neptune — 30.1 AU, 3.88 R⊕
Scale Context

If Earth were a marble (1.3 cm), the Sun would be a 1.4 m ball 150 m away. Neptune would be 4.5 km distant. Proxima Centauri, our nearest stellar neighbor, would be 40,000 km away — farther than Earth's circumference!

The Kuiper Belt (30–50 AU, faint outer ring in the scene) contains icy bodies: Pluto, Eris, Makemake. The Oort Cloud (~50,000 AU) is a hypothesized spherical shell of comets — the outer boundary of the solar system.

Voyager 1, launched 1977, crossed the heliopause (~123 AU) in 2012 and is now in interstellar space.

Knowledge Cards
Asteroid Belt (2.2–3.2 AU)
Between Mars and Jupiter. Contains ~1 million asteroids >1 km. Largest: Ceres (940 km, now a dwarf planet). Total mass ≈ 4% of Moon's mass — too spread out to form a planet (Jupiter's gravity disrupts it).
Saturn's Rings
Extend 280,000 km from Saturn but only ~10 m thick on average. Composed of 93% water ice + silicate dust. Origin: likely a destroyed moon or captured comet ~100 Ma ago.
Kepler's Second Law — watch Mercury
Mercury's orbit is noticeably eccentric (e=0.206). Watch it sweep faster near perihelion and slower at aphelion — equal areas in equal times. This emerges from the gravity integration, not scripted motion.
Why It Matters

Understanding solar system scale is foundational for space exploration mission planning, planetary protection (asteroid deflection), understanding habitability zones around other stars (exoplanet science), and calibrating our place in the cosmos — the basis of scientific humility and curiosity.

Solar System Data
Sun Diameter1,392,700 km
1 AU =149.6 M km
Sim Time0.0 yr
FocusAll (Earth data)
Semi-major axis1.00 AU
Distance now1.00 AU
Speed now29.8 km/s
Light from Sun8.3 min
Period (Kepler 3)1.00 yr
Orbital Energy (all planets)
Kinetic KE—
Potential PE—
Total E—
Drift since reset0.0000%
Units: 10³³ J · E<0 = bound orbits · velocity Verlet
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