Earth
Earth is the third planet from the Sun and the only place we know of in the universe confirmed to host life. Its surface is 70% ocean, its atmosphere is rich in oxygen, and it’s the only planet in our solar system with liquid water on its surface.
| Distance from Sun | 93.3 million miles (150.2 million km) — 1 AU |
| Diameter | 7,926 miles (12,756 km) |
| Length of day | 23.9 hours |
| Length of year | 365.25 days |
| Moons | 1 |
| Temperature | Average of about 59°F (15°C) |
| Atmosphere | 78% nitrogen, 21% oxygen, 1% other gases (argon, CO₂, neon) |
Interesting facts
- Earth is the only planet in our solar system known to have liquid water on its surface.
- If the Sun were the size of a typical front door, Earth would be about the size of a nickel.
- Most of Earth’s volcanoes are hidden underwater; Hawaii’s Mauna Kea, measured base to summit, is taller than Mount Everest.
- Earth’s longest mountain range is almost entirely underwater, running through the Arctic and Atlantic Oceans — four times longer than the Andes, Rockies, and Himalayas combined.
- Earth’s single moon is the fifth largest in the solar system and helps stabilize our planet’s tilt and tides.