Solar System Simulator
How the simulator works
This interactive model places the Sun, the eight planets and their major moons at their real positions for the moment you are viewing, computed from a precise astronomical ephemeris. Drag to orbit, scroll to zoom, and click any body to fly to it and read its key facts. Use the time controls to speed up, reverse or jump to any date, and toggle between a navigable visual scale and the astronomically honest true scale.
The bodies you can explore
Sun
Holds 99.86% of the Solar System’s mass; 1.3 million Earths would fit inside it.
Mercury
0.39 AUA year on Mercury (88 days) is shorter than two of its days.
Venus
0.72 AUSpins backwards and so slowly that a day lasts longer than its year.
Earth
1.00 AUThe only world known to harbour life — and the densest planet in the system.
Mars
1.52 AUHome to Olympus Mons, the tallest volcano in the Solar System (~22 km high).
Jupiter
5.20 AUMore than twice as massive as all the other planets combined.
Saturn
9.54 AUIts rings span ~280,000 km yet are often only ~10 m thick.
Uranus
19.19 AUTipped on its side (98°), it effectively orbits the Sun rolling like a ball.
Neptune
30.07 AUHas the fastest winds in the Solar System — up to 2,100 km/h.
Frequently asked questions
- Are the planet positions accurate?
- Yes. The simulator computes real heliocentric positions for the Sun, the eight planets and their major moons from a precise astronomical model (the same VSOP/ELP-based ephemeris used by observatories), evaluated for the exact moment you are viewing. Press “Now” at any time to snap back to the present instant.
- Why do the planets look so close together?
- By default the simulator uses a “visual” scale that compresses the enormous distances so you can actually see and navigate the whole system. Switch on “True scale” to see the real proportions — the planets become tiny specks separated by vast empty space, which is the honest picture of the Solar System.
- Can I travel forwards and backwards in time?
- Yes. Use the speed control to fast-forward from real time up to about a year per second (or reverse it), drag the date slider, or pick a specific date to see exactly where every planet was or will be.
- Which moons are included?
- Earth’s Moon, the four Galilean moons of Jupiter (Io, Europa, Ganymede, Callisto), Mars’s Phobos and Deimos, Saturn’s Titan, Rhea and Enceladus, the major moons of Uranus (Miranda, Ariel, Umbriel, Titania, Oberon) and Neptune’s Triton, plus Saturn’s rings.
Positions computed with astronomy-engine. Planet & moon imagery: NASA / Solar System Scope (CC BY 4.0). Sizes and distances are adjusted for visibility unless “true scale” is on.