Page 12 - Super Earth Encyclopedia

EARTH IN SPACE

Planet Earth is one of the eight major planets that orbit
our nearest star—the Sun. Along with many smaller objects,
including dwarf planets, moons, asteroids, and comets, these
planets make up our solar system. It is one of the countless
systems of stars and orbiting planets in the universe. But as
far as we know, Earth is the only planet that includes all the
conditions required to create and support life.

Saturn, the second largest
SOLAR SYSTEM planet in the solar system,
When the Sun formed from a vast cloud of has spectacular icy rings
dust and gas about 4.6 billion years ago, some that are visible from Earth.
Like Jupiter, it has a huge
of this dust and gas was left over. It spread out family of moons and a
as a spinning disc around the young Sun. Over stormy atmosphere.
time, most of it clumped together to form the
planets of the solar system—the small inner
rocky planets and the outer gas giants.

Our Sun is a medium-sized
star—a vast ball of hot gas that
lies at the center of the solar
system. All the heat and light About 70 percent of
needed to sustain life on Earth’s surface is covered
Earth comes from the Sun. in water, while most of its
land is divided into seven
huge continents.

Mercury, the smallest
of the rocky planets,
has a surface similar to Mars is smaller and
Earth’s cratered Moon. colder than Earth.
The iron-rich rocks give
Mars its distinctive
Venus is covered with dense rust-red tint.
yellow clouds of acid. With
a surface temperature of
860°F (460°C), it is the hottest
planet in the solar system.

Inner planets
The asteroid belt
The four planets nearest to the Sun— consists of countless
Mercury, Venus, Earth, and Mars—are rocky objects left over
balls of solid or molten rock and metal. from the formation
Each planet has a shallow atmosphere of the planets.
or no atmosphere at all, depending on its
size and gravity, and only Earth has liquid
water. These planets orbit the Sun in the
same plane, but at different distances.

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