Water On Mars
When many view satellite images of Mars, they see a dry, uninhabitable wasteland devoid of any water or life. However, in the past couple of years,
evidence has surfaced which shows that water used to flow on the surface. In the past, Mars could have had oceans and lakes on it's surface just like
Earth currently does.
When water flows over dirt on Earth, there are certain characteristics left in the ground that follow. These structures left in the dirt are seen
satellite images of Mars surface, leading scientists to believe that liquid water used flow on the surface.
Dried up lake bed
In the center of the image is a round- ended chasm or
canyon, deeper than the Grand Canyon on Earth. The walls of the chasm form steps down to its floor, and each step is a layer of tough, strong
rock; there must be weaker rock layers between the steps. These layers extend for hundreds of kilometers, and may have formed originally as sediments
(mud and sand) deposited in an ancient lake.
The evidence seen in the terrain of these images makes it pretty clear
that water was once present on Mars surface.
discusses definitive proof of the shoreline of a
Martian lake, roughly the size of Lake Champlain. (No images, sorry)
Scientists have discovered the first definitive evidence of shorelines on
Mars. Using data from the Mars Reconnaissance Orbiter, the team found evidence of a deep, ancient lake. The finding could be important in the search
for past life on the Red Planet.
More parallels between Mars and Earth are seen with the discovery of
on Mars surface. Hematite is a combination of iron and
oxygen, and this mineral is found on Earth in environments that once interacted with liquid water.
"We believe that the gray hematite is very strong evidence that water was once present in that area," said Victoria Hamilton, a planetary
geologist at Arizona State University (ASU). "We think the deposit is fairly old. It was buried, perhaps, for several hundred million years or more
and now it's being exposed by wind erosion."
This brings up the question: What happened to the water on Mars? Where did it all go? Some scientists believe that the planet began to cool after
it’s formation, diminishing the iron cores ability to generate a protective magnetic field. This allowed the charged particles emitted from the
winds of the Sun to ionize the atmosphere, slowly eating away at it. The loss of Mars atmosphere slowly stripped the planet of its warmth and
pressure, both necessary factors for the presence of liquid water.
However evidence suggests that underneath the frozen carbon dioxide poles of Mars lies millions of gallons of frozen water, the remnants of the
and lakes that once flowed. Orbiting spacecraft have found evidence that water does exist underneath the poles, and measurements of soil
composition have detected high levels of Hydrogen, water being 2 parts Hydrogen and 1 part Oxygen (H2O).
In this false-color map of Mars, soil enriched in hydrogen is indicated by deep blue. Source: the neutron spectrometer onboard NASA's 2001
Mars Odyssey spacecraft.
From the article
"This is the best direct evidence we have of subsurface water ice on Mars." Indeed, he added, "what we have found is much more ice than we ever
It's estimated that there is 100X
as much H2O in the Martian polar ice caps than in all 5 of the Great Lakes.
This frozen water could actually be underneath the surface of the entire planet, as evidence from the odd configuration of debris from asteroid
impacts on the surface suggets. Also, photographic evidence of ice evaporating supports that:
Not only is frozen water found a few inches underneath the surface, but it's also found in the form of
A laser instrument designed to gather knowledge of how the
atmosphere and surface interact on Mars has detected snow from clouds about 4 kilometers (2.5 miles) above the spacecraft's landing site. Data show
the snow vaporizing before reaching the ground.
In an act of seredipity, the Mars Spirit Rover got one of it's wheels jammed in the dirt, and after freeing itself it found
soil, which on Earth is
associated with geysers.
There are two known ways that such silica-rich soil - which is 90% pure silicon dioxide - could have formed. Water heated
by subsurface volcanic activity, with lots of silica dissolved in it, could have percolated up into the soil, and then as it evaporated left the
Some scientists believe that liquid
water may still be present in certain areas of the planet, because under the right conditions, aquifers
could be underground.
Here's a picture indicating that liquid was flowing on the surface in the last few years:
A picture of the exact same spot was taken again in 2001, but nothing
too interesting showed up. However in 2005, a white residue appeared showing either flowing liquid water or the evaporation of liquid that flowed on
the surface: So just in this one area
of Mars, we have an image
providing evidence of flowing liquid, a later image of the same spot showing nothing exciting, and then an image taken after that one showing liquid
water or liquid water that has recently evaporated.
Here is a before an after image of a crater showing a white residue thought to be caused by the evaporation of flowing liquid on the surface:
This image shows evidence of recent underground water seepage on a crater rim:
The evidence is overwhelming: Water once flowed on the surface of Mars.
Life On Mars
So what does this mean for Mars? If water was present, could life have developed? It's definitely a possibility.
Since the oceans and lakes have dried up, does that mean that any living creatures have gone extinct? Not necessarily, because since evidence shows
that water and ice exist under the surface, perhaps life has adapted to the changing environment and moved underground. This is not impossible,
because here on Earth, creatures called extremophiles live in some of the harshest, presumably most uninhabitable places on the planet, such as next
to hydrothermal vents, underwater beneath ice near the poles, or in extremely salty waters.
What would Martian life forms look like? Most scientists agree that the most prevalent life forms would also be the hardest ones to detect:
A highly controversial image taken from the Mars meteorite ALH84001 shows what some see as a fossilized life form, and others see as a rock tricking
Along with this “fossilized life form”, iron-oxide
crystals called magnetite
have been found inside
The meteorite does contain magnetite, but the results of an analysis by Kim and other scientists in 1999 proved inconclusive – the
magnetite’s magnetic signature looked like something in between the signals expected for biogenic and non-biogenic magnetite.
Magnetite is a mineral within it’s own magnetic field, and on Earth it can be created by certain ocean dwelling bacteria. Bacteria use this to their
advantage by growing magnetite crystals in their bodies which help orient them to the Earth’s magnetic field. Maybe bacteria on Mars had the same
But if life developed on Mars, what kick-started the process? Well for one liquid water would need to be present according to our current
understanding of how life develops. But what actually created the 'spark' that got life going? How about
It might even have implications for the origin of life, as
suggested by experiments in the 1950s
Where would Martian life live at? In Yellowstone and other hot springs around the Earth, some forms of life make a living in the mineral rich
Some scientists believe that the molten interior of Mars
has not fully cooled from it’s accretion, and these mineral rich “hot spots” could exist underground in which bacteria would thrive.
Or, if Mars molten core indeed fully cooled and solidified as many believe, life could exist underground where the ice/aquifers are at, or possibly at
the polar ice caps where tons of frozen water exists. The presence of methane hotspots backs this idea up.
“Methane is quickly destroyed in the Martian atmosphere in a variety of ways, so our discovery of substantial plumes of methane in the
northern hemisphere of Mars in 2003 indicates some ongoing process is releasing the gas,” said Dr. Michael Mumma of NASA’s Goddard Space
Flight Center in Greenbelt, Md. “At northern mid-summer, methane is released at a rate comparable to that of the massive hydrocarbon seep at Coal
Oil Point in Santa Barbara, Calif.”
Methane is broken down in just a few months on Mars due to high doses of UV radiation and perhaps dry lightning. So if there’s methane, something is
resupplying it. On Earth methane is released during volcanic eruptions, however Mars volcanoes have been inactive for millions of years. Another
explanation for the presence of methane is underground, basaltic rock getting turned into a mineral called serpentine which releases methane, and it
can seep up through the ground and come out in the atmosphere, however this process requires hot water. The explanation that I like the most is
bacteria producing the
methane. Here on Earth, 90% of methane is produced by bacteria in animals and plants, so maybe on Mars bacteria could be living underground, among the
frozen water or the liquid aquifers, and producing the methane.
Stay tuned, new discoveries might be made everyday.
Source: The Universe
Episode 2: Mars: The Red Planet
Episode 58: Mars: The New Evidence
edit on Sun Jul 10 2011 by DontTreadOnMe because: (no reason given)
edit on Sun Jul 10 2011 by DontTreadOnMe because: (no
edit on Sun Jul 10 2011 by DontTreadOnMe because: (no reason given)