SpaceAbout Earth
Earth, our home, is the third planet from the Sun and the fifth largest planet. It is the only place we know of that is inhabited by living things.
Source: NASA, read on 12 November 2026.
Earth as the measure compared with Earth
Earth is the yardstick for every other world on this site. It is 12,756 km across, and its gravity, 9.8 m/s², is what gives you your everyday weight. Of the eight planets it is the fifth in size: Jupiter, Saturn, Uranus and Neptune are larger.
Day. Earth turns once on its axis in 23.9 hours. From one noon to the next, its day lasts 24 hours.
Year. One trip round the Sun takes 365.2 Earth days. The fact sheet gives 365.2 days, which is why an extra day is added to the calendar in a leap year.
Distance. Earth is on average 149.6 million km from the Sun, between 147.1 million km at its closest and 152.1 million km at its farthest. Sunlight takes 8.3 minutes to arrive. Earth's average distance is the unit astronomers call 1 astronomical unit.
Tilt and temperature. Its axis is tilted by 23.4°. This tilt is what causes the seasons. The mean temperature in the fact sheet is 15 °C.
Moons, rings and magnetism. The fact sheet counts 1 moons for Earth. Rings: no. A global magnetic field: yes.
All the figures
| Diameter | 12,756 km |
|---|---|
| Mass | 5.97 × 10²⁴ kg |
| Density | 5,514 kg/m³ |
| Gravity | 9.8 m/s² |
| Escape velocity | 11.2 km/s |
| Rotation period | 23.9 hours |
| Length of day | 24 hours |
| Distance from the Sun | 149.6 million km |
| Closest | 147.1 million km |
| Farthest | 152.1 million km |
| Orbital period | 365.2 days |
| Orbital velocity | 29.8 km/s |
| Orbital inclination | 0° |
| Orbital eccentricity | 0.017 |
| Tilt of axis | 23.4° |
| Mean temperature | 15 °C |
| Surface pressure | 1 bar |
| Moons | 1 |
| Rings | No |
| Global magnetic field | Yes |
Figures: NASA NSSDCA Planetary Fact Sheet, last updated by NASA on 18 March 2025, read on 12 November 2026. NASA rounds these values. Counts of moons change as new ones are confirmed.
Common questions
How big is Earth?
Earth is 12,756 km across at the equator.
How long is a day on Earth?
From noon to noon, a day on Earth lasts 24 hours.
How many moons does Earth have?
The NASA fact sheet read on 12 November 2026 gives 1.