Earth is our home planet and the only world known to carry life, an ocean planet with a breathable atmosphere, moving continents and a magnetic shield.
At a glance
| radius | 6,370 km (1 × Earth) |
|---|---|
| distance from the Sun | 1 AU (150 million km) |
| sunlight takes | 8.32 minutes |
| one orbit | 365 days |
| orbit eccentricity | 0.017 |
| reflects | 31% of the sunlight it gets |
Read off the piece’s own catalogue, the same values it draws with.
About Earth
Earth is the largest of the rocky planets: an iron core, a slowly churning mantle and a thin crust broken into plates that drift, collide and pull apart, building mountains and setting off earthquakes. Liquid water covers most of the surface, and an atmosphere of nitrogen and oxygen, much of that oxygen made by living things, wraps it in weather. The tilt of its axis gives it seasons as it goes round the Sun.
Its molten outer core drives a magnetic field that deflects most of the solar wind. Where charged particles do get in, funnelled down near the poles, they make the air glow as the aurora. Of all the places we have looked, from the Moon to the moons of the giant planets, Earth remains the only one where life is known for certain.
This is where the piece begins, and the place every distance in it is measured from. Sunlight arrives in minutes; the light of the nearest other star takes years. Everything else in the field guide is seen, first of all, from here.
What you see in the piece
The piece starts here. The clouds are the real global cloud deck from weather satellites, the earthquakes of the past week flash where and when they happened, the night side lights up with towns, and the aurora grows and shrinks with the measured strength of the solar wind. From another star, Earth cannot be seen at all.
Questions
How far is Earth from the Sun?
On average 1 AU, about 150 million km. Its orbit is nearly circular, with an eccentricity of 0.017 and so the distance changes only slightly over the year.
Could Earth be seen from another star?
Not by eye. Earth shines only by reflecting sunlight, and from even the nearest star it would be a faint speck lost in the glare of the Sun beside it.