From far out in space, the Earth looks like a blue ball.
Since water covers three-fourths of the Earth’s surface, blue is the color we see most.
The continents look brown, like small islands floating in the huge, blue sea. White clouds wrap around the Earth like a light blanket.
The Earth is shaped like a sphere. It is 25,000miles around!
It would take more than a year to walk around the whole planet.
A spaceship can fly around the widest part of the sphere in only 90 minutes.
The Sun is the closest star to Earth. A star is a hot ball of burning gas.
The Sun looks very big because it is so close. But the Sun is just a medium-sized star.
Billions of far-away stars are much bigger than our Sun. The burning gases from the Sun are so hot that they warm the Earth from 93 million miles away!
Even though the Sun is always glowing, the night here on Earth is dark. That’s because the Earth rotates every 24 hours.
During the day, the Earth faces the Sun. Then we see light.
During the night, the Earth turns away from the Sun. Then it faces the darkness of space.
Although spaceships have travelled to the Moon, people cannot visit the Moon without special suits.
The Moon has no air or water so plants and animals can’t live there.
Astronauts first landed on the Moon in 1969. They brought back Moon rocks, which scientists are still studying.
There are holes all over the Moon’s surface. Scientists believe that huge pieces of rocks crashed into the Moon millions of years ago and formed the holes.
The Sun warms our planet, and with the Moon, creates the tides in seas and oceans.
The Moon orbits the Earth and in turn, the Earth orbits the Sun.
The Sun and the Moon appear to be the same size in the sky because the Sun is about 400 times farther away than the Moon.
