Terrestrial Planet · Updated May 2026
Earth.
Earth is the third planet from the Sun, the only known world with life, and the densest planet in the solar system. Its 12,742 km diameter is the largest among the rocky inner planets. Roughly 71% of the surface is liquid water — a state stable only because Earth sits inside the Sun's habitable zone, has a thick enough atmosphere to maintain pressure, and a magnetic field strong enough to deflect the solar wind.
Open Earth in the viewer →Key facts
In this viewer Earth uses a custom day/night shader: sunlit oceans and continents on the dayside, glowing city lights on the nightside, drifting cloud cover, atmospheric scattering, and the Moon in real-time orbit. Pause time speed and watch the terminator line move at exactly 1,670 km/h, the speed of Earth's rotation.
Atmosphere
78% nitrogen, 21% oxygen, 1% argon, with trace CO₂, water vapour, and other gases. The troposphere (0–12 km) holds 99% of the water vapour and is where weather happens. Above sit the stratosphere (with the protective ozone layer), mesosphere, thermosphere, and the wispy exosphere that fades into space at 10,000 km up.
Surface
Continental crust averages 35 km thick; oceanic crust about 7 km. Plate tectonics constantly recycles surface material — the oldest oceanic crust is only ~200 million years old, while the oldest continental rocks reach 4 billion. Mount Everest rises 8.85 km; the Mariana Trench drops 11.0 km.
Interior
A solid inner iron core (~1,220 km radius) at ~5,400 °C, a liquid outer core whose convection generates the magnetic field, a silicate mantle with slow plastic flow, and a thin crust. The core temperature is comparable to the Sun's surface.
Formation
Accreted from the protoplanetary disc 4.54 billion years ago. Roughly 100 million years later, a Mars-sized body called Theia struck Earth; the debris coalesced into the Moon. Heavy bombardment delivered most of the water by ~3.9 billion years ago. Life appeared at least 3.5 billion years ago.
Orbit
Average distance from the Sun: 149.6 million km (1 AU). Orbital period 365.256 days. Axial tilt 23.44° drives the seasons. The orbit is nearly circular (e = 0.0167).
Moon
Moon — The Moon is Earth's only natural satellite. It is the fifth largest moon in the Solar System and the largest relative to its planet.
Notable missions
- Apollo (1968–72 · Past) — Crewed missions to the Moon; Apollo 8's "Earthrise" photo reframed how the planet sees itself.
- ISS (1998– · Active) — Continuously crewed since 2000; orbits Earth every 92 minutes at 408 km altitude.
- Earth-observing fleet (Ongoing · Active) — Hundreds of satellites monitor weather, climate, oceans, and land use in near real time.
How to view Earth in 3D
This page is part of an interactive 3D solar system viewer built with Three.js, WebGL 2.0, and custom GLSL shaders. Earth orbits the Sun in real time alongside every other planet, with adjustable time speed, scale sliders, and a fly mode that lets you pilot a spacecraft between bodies under realistic gravity.
Fly to Earth now →Frequently asked questions
How fast does Earth move?
Earth orbits the Sun at about 29.78 km/s (107,000 km/h) and rotates at 1,670 km/h at the equator.
How old is the Earth?
4.54 billion years, dated from the oldest meteorites and lunar samples.
Why does Earth have seasons?
Its 23.44° axial tilt changes which hemisphere leans toward the Sun across the year — not changing distance from the Sun.
Sources & methodology
Numbers cross-referenced with the sources below; surface and atmosphere descriptions reflect findings as of May 2026. Renderings in the 3D viewer use textures based on Solar System Scope and NASA imagery.