ROVING OVER
MARS
Is there life on Mars? Nature
has many secrets, but few excite earthlings more than this one. Movies, books, real time
reports of people spotting Martians...we have done it all. Why is the red planet so
irresistibly attractive?
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Of all the planets in the Solar System, Mars is the most
Earth-like. It is the most travelled space destina-tion because it is easy to reach.
Comparatively.
Here are some interesting tidbits about it:
Mars is half the size of earth, but has the same amount of dry land.
Ferric oxide
or rust iron gives Mars its blood red colour. And it is named after the Roman god of war.
It takes
Mars twice as long as earth to go round the sun. But a Mars day is only 40 minutes longer!
You would
weigh 1/3rd as much on Mars as you do on earth.
Mars has
mountains, valleys, polar ice caps and dry riverbeds. It has seasons, an atmosphere and a
solid, rocky surface.
In winter,
temperature dips to —118 o C. Summers at the Martian equator are like the winters in
Antarctica! |
Life on Mars
– the water link
First solid evidence came in 1984 when a former NASA (National Aeronautics and Space
Admini-stration) scientist found a potato-like meteorite in Antarctica. It was a rock
chipped off from Mars, said NASA, and crashed into earth some 13,000 years ago.
Life-sup-porting carbon compounds and magnetite were present in it. The meteorite was
about 4-4.5 billion years old-- when Mars first came into existence. At that time, Mars
was warmer and wetter, and had rivers and lakes. There was water.But was there life?
The first proof of life came in 1996. US Mars Global Surveyor sent pictures of an ancient
riverbed below a wide canyon called "Nanedi Vallis" near the equator.These signs indicated the presence of a long-term water flow-- of
a riverbed. Glaciers, snow packs and water-carved gullies were also found. |
This dismissed what two Viking spacecrafts had recorded
in 1974. That there was no sign of life in the Mars’ soil.
The Pathfinder, Odyssey and the recent Spirit,
Opportunity mis-sions have found out more.That life had frozen on Mars...
Lessons from Mars?
In 1997, the US Pathfinder and the Sojourner rover startled everybody. There were signs of
life-supporting systems in Mars that had stopped functioning!A rocky plain at the mouth of
a channel, Ares Vallis, is apparently carved out by running liquid water. Geologists say
that this deluge may have released 100 million cubic metres of water per second. But no
oceans exist today. Only a cold desert. Then there are pebbles rounded by water, show-ing
that Mars had a warm, thick atmosphere. Now there is perma-nent frost.
How did the Martians live and Is there life on Mars?
Nature has many secrets, but few excite earthlings more than this one. Movies, books, real
time reports of people spotting Martians...we have done it all. Why is the red planet so
irresistibly attractive? die? Can it happen to earthlings too? Any lessons for us to learn
here?
Mars may have been trapped in an ice age.Or there
may have been an excessive generation of carbon dioxide to keep the water warm. In other
words, a greenhouse effect.
But how did Mars begin to produce such volumes of CO 2 ? It was triggered by volcanic erup-tions, say sceintists. And with
Spirt finding volcanic ash on Martian surface, this seems to be the most viable explanation.
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