picture of the day
“Dodo-Goldilocks” trench dug by
the Phoenix Lander.
Credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University
Jun 20, 2008
The Search for Water on Mars Continues
No indications of water vapor are in the soil samples excavated
by the Phoenix lander.
On June 11, 2008, NASA
conducted the first experiment designed to detect water on
Mars. After digging what the researchers from the University
of Arizona refer to as a “practice trench” approximately
seven centimeters deep, the robot arm onboard Phoenix tipped
the sample into the Thermal and Evolved-Gas Analyzer.
Although there was a false-start due to clumping of the rock
dust, the TEGA was finally able to bake the material at 35º
C in an attempt to drive off any volatile compounds,
especially water vapor. No water was detected.
After the first evaluation, the soil was heated to 175º C,
but to no avail. William Boynton, team leader in charge of
the TEGA package, said he was not surprised by the null
result because the sample “sat out in the Martian sun for
several days” and any water ice most likely sublimed into
the thin atmosphere.
Early next week, researchers will command the TEGA to raise
its oven temperature to 1000º C so that any water
“chemically bound” to the compounds in the soil will be
released. Said Boynton: "We expect there's a high
probability that we would find minerals with
chemically-bound water, which would release their water at
higher temperatures." They also hope that the mass
spectrometer package will see traces of sulfur dioxide or
carbon dioxide in the mix, an indication that water once
reacted with the minerals on Mars.
A piece of the white substance in the bottom of the trench
was left by the robotic scoop, so NASA will be watching it
to see if it changes over time. It might be ice according
their hypothesis, so if it shrinks in size it could be due
to sublimation. The atmosphere on Mars is so dry and so
tenuous that ice will not enter its liquid phase out in the
open but instead evaporates into gas.
As previous Thunderbolts Picture of the Day articles have
stressed, there is probably no water on Mars so the white
chunk is most likely broken from a layer of salt or from
other minerals like those discovered at lower latitudes. The
forces that dumped the deposits on Mars were global. Phoenix
mission analysts are in a “wait and see” mode but we predict
that the small wedge of rock will not sublime.
Phoenix will soon begin digging another trench in one of the
polygonal shapes that are visible for many kilometers around its landing
site. Planetary scientists have suggested that the polygons are similar to what
can be found in the Arctic tundra where “frost heave” sorts stones and
permanently frozen ground into regular contours. Expansion and contraction of
subsurface ice could have done the same thing on Mars, so NASA has preserved the
location while they conducted their practice drills in less crucial real estate.
Mars is rich in silicon dioxide and magnesium sulfate. Both chemical compounds
are white and crystalline so they look something like ice when formed into
slabs. The Opportunity rover found expanses of
silicon dioxide (quartzite) covering many square kilometers as it slowly
made its way to the rim of Victoria Crater. NASA scientists refer to Martian
quartzite blocks as “cobbles” and “pavement” because they resemble sidewalks and
concrete roadways here on Earth.
The Spirit rover suffered a breakdown in one of its drive wheels about two years
ago, causing it to drag rather than roll smoothly. The mechanical failure was
actually a boon in one respect – as the wheel plowed through the dust and sand
it uncovered a layer of
bright white soil that was subsequently identified as magnesium sulfate.
Neither rover detected water, although some observations led the science teams
to believe that water once existed on Mars.
Spacecraft in orbit around the Red Planet have returned images of what appear to
be water features.
Previous Picture of the Day articles have taken issue with that
interpretation, however. “Ancient glaciers”, “oceans” and “fast flowing
torrents” of water probably never existed on Mars. NASA scientists do not
concede that electricity is capable of creating structures and terrain that look
like they were carved by liquid, so no other hypothesis is available to them.
The remnant topography on Mars is not rounded or softened as if by a deluge, nor
does it conform to slow weathering by rainfall or blowing dust. The formations
are sharp, angular and fresh looking, as if they were sculpted quickly and with
The northern latitudes, in particular, appear to have been obliterated. In fact,
Electric Universe theorist
Wal Thornhill has written that the northern region of Mars was the scene of
a cosmic plasma storm that electrically sputtered millions of square kilometers
out of the crust, subsequently redistributing the finely divided dust all over
the rest of the planet as well as hurling it into space.
In such a cataclysmic event, all the water ice that might have once existed on
Mars would have been disintegrated and blasted away, never to return.
By Stephen Smith
Please visit our new "Thunderblog" page
Through the initiative of managing
editor Dave Smith, we’ve begun the launch of a new
presentations of fact and opinion, with emphasis on
and the explanatory power of the Electric Universe."
new: online video page
The Electric Sky and The Electric Universe