Page 23 - (DK) Eyewitness - Mars

Biology tests of Martian soil A LANDER’S LABORATORY Nutrient Gas analyzer
Each Viking lander had an
supply
onboard laboratory to test soil
Mechanical arms on the Viking landers collected soil samples. One instrument fed a
samples and mixed them with water and life-supporting sample with nutrients and tried to
chemicals. Sensitive instruments checked the mixtures, detect gases normally produced
looking for signs of life such as gas molecules given off by by living organisms. None were
microscopic bacteria. The dusty Martian soils proved sterile, found. Another test was for Helium gas
plantlike cells. Soil was heated,
however. Since winds mixed dust from all over the planet, and a bright light encouraged cells
most scientists believed these negative results would be the to grow, but without success.
same everywhere on Mars.
Martian soil
Bright lamp promoted wetted with
growth of any plant nutrient
VIKING LANDERS cells for five days solution
The Viking 1 and 2 landers were the first
spacecraft to conduct long-term research on Gases from soil
another planet. Each lander had a robotic arm sample separated
that scooped up soil samples for testing. Dish
There were also two rotating television antenna
cameras and instruments to study Martian
weather. The landers operated until 1982,
transmitting 1,400 images to Earth.

Cameras Heat broke down Gas analyzer
any organic chemicals in the soil
Meteorology
instruments and converted them into gas

Robotic
Robotic arm arm’s scoop
and scoop

DIGGING IN THE DIRT
The Viking lander’s robotic trenching arm
with its sharp scoop is tested on Earth
before the mission’s two launches. The first
experiments on Martian soil samples
suggested the presence of life, but later
review of the results found there was no life.
The lander’s meteorology instruments are
contained in the other extended arm.

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