By now, I'm
sure you've heard there's water on Mars. Free-flowing, very salty water. The
announcement came a day or two after I saw "The Martian", and I
decided to dig deeper into this Martian water issue.
In the late
19th century, Giovanni Schiaparelli reported seeing 'canali' on Mars'
surface, meaning channels. A few years later, Percival Lowell confirmed long
lines on Mars' surface, and suggested they were an attempt by an advanced
Martian culture to save their drying planet by moving water from the poles.
Ultimately, these canali / canals did not exist. I haven't found any explanation
for why or how they were 'seen' in the first place.
Most of Mars'
northern hemisphere is fairly flat with few impact craters; the southern is
covered in impact craters. In between is an area of mesas, flat-floored valleys
with cliff walls, and other rough terrain. Some features imply that water was present
in the distant past, that free-flowing water created paths through the stones.
Where did it all go?
Some is
still there. Surrounding the bases of those mesas and at the bottoms of those
cliffs are what appear to be masses of rock, called lobate debris aprons.
In Alaska, we saw a glacier that was so covered in dirt and rocks (picked up
during its travel), it just looked like a muddy pile on the edge of the bay.
That's what these debris aprons are... solid ice covered in rocks and dirt.
Recent
reports from SPICAM, which is circling Mars to study its atmosphere,
show that the Martian atmosphere is super-saturated with water vapor. Water
vapor doesn't just form droplets when it gets chilled, it needs a speck of dust
or something to condense around. If there isn't enough dust, the vapor keeps pushing
upward. Eventually, that vapor gets so high, it splits into hydrogen and
oxygen, which escape into space, but the article I read said even at 50 km, the
atmosphere was super-saturated.
So, Mars is
not the super-arid place we thought it was.
How would
that have changed the survival techniques used in "The Martian"? In
his attempt to produce water to grow crops, could he have 'mined' it from one
of these rock piles? Devise a method to condense it from the air? Purified the
salty stuff?
What do you
think?
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