The New Childrens Encyclopedia

26

1960s 1970s

TIMELINE OF MARS EXPLORATION

1964

Mariner 4 (US)

the first success

returned 21

images.

1960

Korabl 4

(USSR) did not

reach Earth

orbit.

1962

Mars 1 (USSR)

lost contact on

way to Mars.

1971

Mariner 9 (US) the

first successful Mars

orbiter.

1976

Viking 1 (US) made the first

successful landing on Mars.

1969

Mariner 7 (US)

was a success

and returned

126 images.

The red planet

Aside from Earth, Mars is the most

suitable planet for humans to live on.

It looks red because iron minerals in

its surface rocks have rusted. In the

past, it was much more like

Earth than it is today.

GIANT CANYONS

The Valles Marineris are more

than 2,500 miles (4,000 km)

long—10 times the length of

the Grand Canyon—and

extend a fifth of the way

around Mars. The canyon is

about 5 miles (7 km) deep and

more than 375 miles (600 km)

wide in the center.

VALLES MARINERIS

The canyon system was

discovered by the

Mariner 9 orbiter (after

which it was named).

1973

Mars 5 (USSR)

Orbiter got 22

days of data.

Volcanoes Mars has the largest

volcanoes in the solar system. The most

impressive is Olympus Mons, which is

375 miles (600 km) across and more

than 16 miles (26 km) high. The volcano

hasn't erupted for millions of years.

These dark

circles are

volcanoes.

O

There are ice caps at both Martian poles,

but they are much smaller than the Earth’s.

Each pole is different. The northern sheet is

about 2 miles (3 km) thick and mainly water

ice. The southern polar cap is colder but

thicker, and made of water ice with a coating

of carbon dioxide ice. The polar caps melt

and shrink in summer, then grow in winter

when the temperature drops.

North

polar

ice cap

POLAR ICE CAPS

SPACE