The two closest to the
Earth planet - Mars and Venus - once had vast oceans, extending over many
millions of square kilometers. But all the planets with liquid water on the
surface is very fragile. Venus could not keep their oceans, and they vanished
into space. Recently we learned that Mars lost most of their water, then it
turned into a dry and cold desert.
And you, the Earth?
What about you? I do not like: what about us ? What is the future in store for
the most valuable resource of our planet? Can we squander irreplaceable
reserves of water and turn the Earth into a desert-like Venus or Mars?
If the greenhouse
effect is a little raise the planet's temperature, the water can start to
evaporate into space.
The water at the
molecular level
The substance, which we
call water consists of two hydrogen atoms and one oxygen atom. The core
consists of a hydrogen atom from a single positively charged proton, and
rotates around a negatively charged electron. Nevertheless, in the core may
also contain one uncharged neutron. Even with this neutron nuclear charge
remains positive, but there is one important difference: the atom with a
neutron in the nucleus is much heavier than normal hydrogen.
Chemists call this
"heavy" hydrogen by deuterium. All chemical reactions deuterium
behaves just like a normal hydrogen; he's just harder. If a water molecule
hydrogen atoms replaced with deuterium, it will remain the same taste, it all
the same will be watered flowers - the only difference is that it will become
harder.
And the thing is this
additional weight: gravity pulls deuterium stronger than normal hydrogen. When
hydrogen and deuterium in the atmosphere of our planet, hydrogen rises much
higher. And if the planet's gravity is not strong enough - as, for example,
Venus, Earth and Mars - ordinary hydrogen can rise so high that it will not
return back and leave the planet. Deuterium is also withheld the gravity of the
planet.
The initial ratio of
hydrogen to deuterium
In 1995 probe NASA
«Galileo" measured ratio of deuterium to hydrogen in the atmosphere of
Jupiter. The measurement results indicate a ratio of 40,000 to one. Jupiter - a
planet so massive that it can not leave any hydrogen or deuterium. So planetary
scientists, believe that all the planets of the solar system were formed with
the ratio of hydrogen to deuterium.
The actual ratio
If you zacherpn?te a
glass of water from any ocean of the Earth, of any lake on every continent,
from alpine glaciers or Yellowstone geyser, the ratio of deuterium to hydrogen
atoms in it would be 6,250 to one. Not 40,000 to one.
Why is that? Once upon
a time, our planet contained a huge amount of hydrogen. Gradually hydrogens
left Earth, lowering the ratio from the original 40 000 to 1 to 6250 to 1.
Thus, so far the Earth already lost 80% of its hydrogen and the planet since
hydrogen contained mostly water loss hydrogen equivalent water loss .
Space Station, NASA Pioneer in 1978 launched a probe into the atmosphere of Venus, which
measured its physical and chemical properties. One of the most surprising
discoveries was the ratio of hydrogen atoms to deuterium - only 62 to one
hundred times lower than in the world.
What follows from this
conclusion? Venus was once wet planet, but then turned into a dry desert. As we
know, the temperature on the surface of Venus - more than 460 degrees Celsius.
Once there were oceans on Venus, but they are boiled away, and ultraviolet
sunlight split the water molecules into atoms of oxygen and hydrogen. As a
result, light hydrogen atoms have risen too high and the "flowed" in
space, while the heavy deuterium remains in the atmosphere. The ratio of
hydrogen to deuterium on Venus - evidence of what happened to our neighbor of
billions of years ago.
As for Mars rover
received NASA «Kyuriositi" data indicate that the ratio of deuterium to
hydrogen on this planet seven times less than on Earth. This tells us that Mars
and Venus are both in the past has lost almost all of its water.
The total volume of
water on Mars (in the icy polar caps, in the atmosphere, the ice layers beneath
the surface of the planet) would cover the entire planet ocean depth of 21
meters. Measurements of the ratio of hydrogen-deuterium tell us that early Mars
was seven times more water - enough for ocean depth of 137 meters.
Venus-What's next?
Venus and Mars.
Planetary scientists know that once upon a time these two planets were wet -
just like Earth. None of them could not hold their water long enough for life.
Their lesson is simple: water worlds are very fragile. Water worlds that can
survive the devastating events, whether natural or caused by their inhabitants
- are very rare and therefore priceless.
If we allow the
temperature of the planet to rise a couple of degrees above, we can go through
this little ecological disaster. But who knows whether they will not be a few
degrees the last straw that will launch the same deadly process that once
deprived of water Venus and Mars?
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