The New Childrens Encyclopedia

The solar system is our local area of

space. As its center is the Sun, our

nearest star, which accounts for

almost all (99.9 percent) of the solar

system’s mass. The Sun’s gravity keeps

the planets in their orbits.

The solar system

INNER PLANETS

The four planets nearest the

Sun are called the inner

planets. They are also known as

the rocky planets because they

are balls of rock and metal.

They are dense and have

central cores made of iron.

All of the planets and

asteroids go around the

Sun in near-circular

orbits in the same

direction (west to east).

MARS

MERCURY EARTH

THE SUN VENUS

DISTANCE FROM THE SUN

The red line to the right shows the

distance of each planet from the Sun

in millions of miles and kilometers.

Mercury is closest and Neptune

is farthest away. Earth is about

93 million miles (150 million km)

from the Sun.

SUNMercury Venus Earth Mars

0 150 (250)

In any year there can be up to seven solar

or lunar eclipses, when light from the Sun

or Moon is blocked for a short time. Solar

eclipses are more common, but are seen

only in a narrow area. Lunar eclipses can

be seen anywhere on Earth where the

Moon is shining in the sky.

A “diamond ring

effect” appears just

before or just after

an eclipse of the

Sun. Then the

Sun’s corona

(atmosphere) can

be seen around

the Moon.

LUNAR AND SOLAR ECLIPSES

People at the center of the Moon’s shadow

experience a total solar eclipse.

The Moon

The Earth

O A lunar eclipse happens when

the Earth passes between the Sun

and the Moon, so that the Earth

casts a shadow on the Moon.

O A solar eclipse happens when the

Moon passes between the Earth and the

Sun, casting a shadow on the Earth. A

total eclipse lasts for up to eight minutes.

SOLAR ECLIPSE

The Sun

SPACE

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(c) 2012 Dorling Kindersley. All Rights Reserved.(c) 2012 Dorling Kindersley. All Rights Reserved.