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The Solar System

Our cosmic neighborhood — 8 planets, 200+ moons, and countless asteroids bound to the Sun by gravity. Everything orbits in the same flat plane, a relic of the spinning disk of gas and dust that formed 4.6 billion years ago.

How Gravity Shapes Orbits

The Sun holds 99.86% of the solar system's mass. Its gravity curves space-time like a heavy ball on a trampoline — planets "fall" around this curve in perpetual free-fall, creating stable elliptical orbits.

Mass = Gravity Curved Space-Time Stable Orbits

The Sun — Our Star

A G-type main-sequence star fusing 600 million tons of hydrogen into helium every second. Its core reaches 15 million°C, and its magnetic field drives the solar wind — a stream of charged particles that reaches every planet.

15M°C

Core Temp

99.86%

System Mass

4.6B yr

Age

Inner Rocky Planets

Mercury, Venus, Earth, and Mars — small, dense, with solid surfaces. They formed in the warm inner disk where metals and silicates condensed. All four have iron cores and rocky mantles.

Mercury

88-day orbit

Venus

Hottest planet

Earth

Liquid water

Mars

Largest volcano

Outer Gas & Ice Giants

Jupiter and Saturn are gas giants — mostly hydrogen and helium with no solid surface. Uranus and Neptune are ice giants — water, ammonia, and methane ices under thick atmospheres. All have ring systems and dozens of moons.

Jupiter — 79 moons Saturn — Iconic rings Uranus — Tilted 98° Neptune — Winds 2,100 km/h

Beyond the Planets

The solar system doesn't end at Neptune. The asteroid belt between Mars and Jupiter holds leftover rocky debris. The Kuiper Belt beyond Neptune contains icy dwarf planets like Pluto, and the distant Oort Cloud is a shell of comets extending a light-year out.

Asteroid Belt: Rocky debris, 2–3.5 AU

Kuiper Belt: Icy bodies, 30–50 AU

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