EARTH
EARTH
The Earth is our home planet. It is normal and familiar to us. All the people who have ever lived, and almost all the events in recorded history, happened on this planet. From orbit, the curvature of the Earth is clearly visible, and also the thin blue line of the atmosphere, as seen in this Apollo 16 photograph.
Earth Facts
Earth Facts
Average diameter: 12,742km (7,918 miles)
Tilt: 23.5 degrees
Rotation Period (day): 24 hours
Orbital Period (year): 365.26 Earth days
Distance from the Sun: 149,598,023 kilometres (149 million, 598 thousand and 23 kilometres), or 92,955,902 miles (92 million, 955 thousand, 902 miles)
Average Orbital Speed: 29.78 kilometres per second, or 18.5 miles per second
Moons: 1 (The Moon)
Planet Earth as seen by Apollo 16 Astronauts on their way to the Moon, in April 1972. Only 24 people - all of them Apollo astronauts - have seen the Earth from this vantage-point.
The Moon is the Earth's constant companion. Below is a scale image of the Earth-Moon system.