EUMETSAT, AttributionEarth
The only known inhabited world, and the yardstick for every other planet
Overview
Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is made possible by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its ocean, which covers 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is dry land, which is predominantly located within Earth's land hemisphere in the form of continental landmasses. Most of Earth's land is at least somewhat humid and covered by vegetation, while large ice sheets at Earth's polar deserts retain more water than Earth's groundwater, lakes, rivers, and atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth has a liquid outer core that generates a magnetosphere capable of deflecting most of the destructive solar wind and cosmic radiation.
Source: Wikipedia
Why it matters
- About 71% of the surface is covered by liquid water oceans; the only planet with confirmed plate tectonics.
- Its oxygen-rich atmosphere and ozone layer are biosignatures we hope to recognise on exoplanets.
- Hosts a single large Moon that stabilises Earth's axial tilt and drives the tides.
System
- Discovered
- known since antiquity
- Star
- Sun · G2 V · 5,772 K · 1 M☉
- System
- 8 known planets
Orbit in the Solar System
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| Mercury | 88 d | 0.387 AU | 0.38 R⊕ | 0.055 M⊕ | 440 K |
| Venus | 224.7 d | 0.723 AU | 0.95 R⊕ | 0.82 M⊕ | 737 K |
| Earth | 365.2 d | 1 AU | 1 R⊕ | 1 M⊕ | 288 K |
| Mars | 687 d | 1.52 AU | 0.53 R⊕ | 0.11 M⊕ | 208 K |
| Ceres | 4.6 yr | 2.77 AU | 0.07 R⊕ | 0.94 ×10²¹ kg | — |
| Jupiter | 11.9 yr | 5.2 AU | 1 R♃ | 1 M♃ | 163 K |
| Saturn | 29.4 yr | 9.57 AU | 0.84 R♃ | 95.11 M⊕ | 133 K |
| Uranus | 83.7 yr | 19.16 AU | 0.36 R♃ | 14.53 M⊕ | 78 K |
| Neptune | 163.7 yr | 30.18 AU | 3.88 R⊕ | 17.08 M⊕ | 73 K |
| Pluto | 247.9 yr | 39.48 AU | 0.19 R⊕ | 13 ×10²¹ kg | 48 K |
| Haumea | 282 yr | 43.1 AU | 0.12 R⊕ | — | 50 K |
| Makemake | 306.6 yr | 45.6 AU | 0.11 R⊕ | 3.1 ×10²¹ kg | — |
| Eris | 561.3 yr | 67.9 AU | 0.18 R⊕ | 17 ×10²¹ kg | 43 K |
| Sedna | 12,676.2 yr | 544 AU | 0.08 R⊕ | — | 12 K |
By the numbers
- Radius
- 1 R⊕6,371 km
- Mass
- 1 M⊕5.97 ×10²⁴ kg
- Orbital period
- 365.2 d1 yr
- Distance from Sun
- 1 AU150 million km
- Eccentricity
- 0.017nearly circular
- Mean temperature
- 15 °C288 K
- Gravity
- 9.8 m/s²1 g
- Day length
- 24 h1 Earth days
- Moons
- 1
- Density
- 5.51 g/cm³
- Axial tilt
- 23.4°
Sources
Image: EUMETSAT, Attribution · Attribution · image page
Text: Wikipedia (CC BY-SA 4.0). Taglines and highlights are editorial.