There were a lot of explorations done to search for other
heavenly bodies on the universe where man could possibly live! Mars is the
nearest feasible to explore. Did NASA found something there worth to prove that
we could live there? Well, they did more than that.
NASA has found out that Mars have once a habitual
environment! As a matter of fact, NASA’s curiosity rover has collected
compelling evidence that ancient Mars was a very wet place.
They were looking for water on Mars? Yes, some of it fit to
drink, there’s water, there’s water everywhere.
Thanks to
discoveries by NASA's Curiosity rover, shown on the right is the picture of
ancient Mars that has emerged during the past few months, which has been
exploring the Red Planet since touching down inside Gale Crater in August 2012.
Presented together recently here at the European Planetary
Science Congress, though the announcements have come in dribs and drabs, they
provide compelling evidence that Mars was quite wet in the distant past.
Scientists presented details of the rover’s most exciting
finds, made before it began the long drive toward the towering Mount Sharp this
past July, during many sessions at the conference, which was held Sept. 8 to 13
in London.
And the words that could be heard most often were hydrogen,
hydration, rocks and water. Especially water.
According to Melissa Rice of the California Institute of
Technology in Pasadena, "We know that on there was what we interpret to be
a habitable environment, where water was good enough for us to drink." She
said that after a presentation on imaging results from Curiosity’s workhorse
Mastcam instrument.
She talked about rocks that Curiosity studied earlier this
year, finding evidence that ancient Mars could have supported microbial life.
"We know that we had an initial habitable environment
when these rocks formed, and then sometime later — we don't know when — these
rocks had water flowing through them, through these fractures, leaving calcium
sulfate behind," Rice said. "We don't know if that era would have
also been habitable, but it tells us that there were at least two major wet
stages."
Mudstone was one of the rocks Rice mentioned that Curiosity
drilled into. Researchers found clay minerals inside, which meant either
formation in, or substantial alteration by, water on Mars.
Further, this water had to be neutral and benign. That's a
big deal as far as habitability goes; Curiosity's smaller, older cousins,
NASA's Spirit and Opportunity rovers, after touching down in 2004, found plenty
of evidence of ancient Martian water, but most of it was likely extremely
acidic.
According to presenter Aileen Yingst, a Curiosity science
team member from the Planetary Science Institute in Tucson, Ariz, "It’s
amazing that we found a mudstone, Mudstones mean that you have very fine grains
inside the rock — meaning that these grains settle down slowly. On Earth, that
usually means that it happened because of wind or water. And we think that it
was probably water."
The mudstone formed in a place where water was calm, such as
a lake, at least that was Researchers think — perhaps an ideal place for
microbes to survive and reproduce.
"If you’re a microbe that is trying to get a hold on a
place to live, you don’t necessarily want to be living in churning water; it’s
not good for you to start growing and thriving," Yingst said. "[Calm
lake] water is a better place to live."
A tiny pebble that Curiosity rolled over and broke apart is
another rock that received a lot of attention at the conference is Tintina.
Strongly hinting at the presence of hydrated minerals that
formed when water flowed through billions of years ago, the small piece of rock
revealed a snowy-white interior.
More strong evidence of Mars' wet past comes from
Curiosity’s discovery of calcium sulfate veins — fissures in the surface rock
that, once sampled with a laser-firing instrument called ChemCam, were shown to
contain sulfate.
Yingst also added that, "If you have veins, then you
have had water that has some sort of rock-forming mineral solution that has
dissolved in the water, transported somewhere else and then deposited again. So
it’s just another indicator that you’ve had about water activity".
And then there are the ancient river deposits.
One such feature of the Martian landscape, studied by
Curiosity while it was at a small depression near its landing site called
Yellowknife Bay, is an outcrop researchers dubbed Shaler.
Comprises thin, inclined layers of sediment, Shaler is an
example of cross-stratification. Features resembling Shaler are commonly formed
by rivers here on Earth; turbulent water creates "dunes" on the
riverbed, which slowly migrate in the direction of the current.
Researchers claims that what Curiosity has seen are the
remnants of that migration process.
According to presenter Sanjeev Gupta from Imperial College
London, a member of the Curiosity team. "The grain size there are small
pebbles and coarse sand grains, too large to be lifted up and transported by
wind, so the only way we can produce these dunes is by water flow".
"And these look exactly like the sort of features I’ve
looked at on Earth formed by ancient rivers," Gupta added. "So we can
tell that these outcrops are clear evidence for sustained water transport and
dune migration. When they are preserved, they are recording minutes to hours of
motion, and they’ve been preserved for millions to billions of years."
The water flows that produced the dunes probably occurred
billions of years ago, Gupta said. Gupta also added that a process that will
take months, Scientists are still analyzing Curiosity's images of the deposits.
Curiosity is now embarked on a long journey to Mount Sharp,
which rises 3.4 miles (5.5 kilometers) into the Martian sky from Gale Crater's
center.
By next May or June, team members claims that the 1-ton
rover may finally arrive at the mountain's base. Curiosity will then climb up
through Mount Sharp's lower reaches, studying the many rock layers as it goes.
"Who knows what’s there? I hope we find evidence for
ancient landscapes, and how they changed, how environments evolved," Gupta
said.
Another goal is to analyze rocks containing clay minerals at
the foothills of Mount Sharp, and understand how they changed into rocks
containing sulfate minerals.
"We want to understand what are the mechanisms for
those rocks to form," Gupta said. "Was it clay minerals deposited in
a lake? Or digenesis, which is when the rocks have been changed when fluids
flowed through them and altered the minerals?"
Since before the rover's November 2011 launch, Mount Sharp
has been Curiosity's primary destination. Mission scientists are eager to find
out what the rover discovers there.
"I think the door is wide open and the best is yet to
come," Yingst said. "Judging from the exciting stuff that we found so
far, it’s only going to get better."
If NASA could find a way to cultivate water there on Mars,
we certainly could live there!
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