Free~18 min
Solar System Scale
True distances and sizes of planets in perspective
Solar System Scale
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How it works
The solar system is overwhelmingly empty space. The Sun contains 99.86% of the system's mass. If the Sun were a basketball (24 cm diameter), Earth would be a 2 mm peppercorn 26 meters away, and Jupiter would be a 2.5 cm marble 135 meters away. Neptune would be over 770 meters away. The planets' sizes span 4 orders of magnitude: Mercury (4,879 km) to Jupiter (139,820 km). Distances span even more: Mercury at 0.39 AU to Neptune at 30.07 AU. One AU is about 150 million km. Light takes 4.2 hours to reach Neptune from the Sun.
Step-by-step
- Adjust time speed, size exaggeration, and distance scale, then click a planet or use Focus Planet to fly to it.
- Toggle orbit lines to compare the orbital paths.
- The data chip reports the focused planet's distance, period, light time, diameter, and mass.
Key formulas
- Astronomical Unit: average Earth-Sun distance, used as the standard measure of solar system distances
- Light travel time: even at 300,000 km/s, sunlight takes 8.3 minutes to reach Earth
Frequently asked questions
- If Earth is 1 AU from the Sun, how far is Jupiter in AU?
- Jupiter orbits at ~5.2 AU from the Sun.
- How many Earths could fit inside Jupiter by volume?
- Jupiter's radius is ~11.2× Earth's. Volume scales as r³: 11.2³ ≈ 1,400 Earths.
- How long does light take to travel from the Sun to Neptune?
- Neptune is ~30 AU away. Light crosses 1 AU in ~8.3 min. 30 × 8.3 ≈ 249 min ≈ 4.15 hours.