We discuss and comment on the role agriculture will play in the containment of the CO2 problem and address protocols for terraforming the planet Earth.
A model farm template is imagined as the central methodology. A broad range of timely science news and other topics of interest are commented on.
Tuesday, December 13, 2011
Early Earth Earth Like?
This does confirm that relying
solely of planetary out gassing may not be overly sound and that bombardment
may actually work better.
Since it is a reasonable
conjecture that rocky planets such as Earth and Venus are in fact natural
ejecta from the body of Jupiter, bombardment by Comets will make an atmosphere
It really makes a lot of sense
that the deep rocks on Earth have not changed much at all since it is apparent that
the recycling rate is increditably slow and that the proposed radical changes
may simply be impossible.
Besides, the weight of evidence
is presently in favor of some level of inoculation immediately after the planet
The debate goes on.
Setting the Stage for Life: Scientists Make Key Discovery About the
Atmosphere of Early Earth
Newswise — Troy, N.Y. – Scientists in the New York Center for
Astrobiology at Rensselaer Polytechnic Institute have used the oldest minerals
on Earth to reconstruct the atmospheric conditions present on Earth very soon
after its birth. The findings, which appear in the Dec. 1 edition of the
journal Nature, are the first direct evidence of what the ancient
atmosphere of the planet was like soon after its formation and directly
challenge years of research on the type of atmosphere out of which life arose
on the planet.
The scientists show that the atmosphere of Earth just 500 million
years after its creation was not a methane-filled wasteland as previously proposed,
but instead was much closer to the conditions of our current atmosphere. The
findings, in a paper titled “The oxidation state of Hadean magmas and
implications for early Earth’s atmosphere,” have implications for our
understanding of how and when life began on this planet and could begin
elsewhere in the universe. The research was funded by NASA.
For decades, scientists believed that the atmosphere of early Earth was
highly reduced, meaning that oxygen was greatly limited. Such oxygen-poor
conditions would have resulted in an atmosphere filled with noxious methane,
carbon monoxide, hydrogen sulfide, and ammonia. To date, there remain widely
held theories and studies of how life on Earth may have been built out of this
deadly atmosphere cocktail.
Now, scientists at Rensselaer are turning these atmospheric assumptions
on their heads with findings that prove the conditions on early Earth were
simply not conducive to the formation of this type of atmosphere, but rather to
an atmosphere dominated by the more oxygen-rich compounds found within our
current atmosphere — including water, carbon dioxide, and sulfur dioxide.
“We can now say with some certainty that many scientists studying the
origins of life on Earth simply picked the wrong atmosphere,” said Bruce
Watson, Institute Professor of Science at Rensselaer.
The findings rest on the widely held theory that Earth’s atmosphere was
formed by gases released from volcanic activity on its surface. Today, as
during the earliest days of the Earth, magma flowing from deep in the Earth
contains dissolved gases. When that magma nears the surface, those gases are
released into the surrounding air.
“Most scientists would argue that this outgassing from magma was the
main input to the atmosphere,” Watson said. “To understand the nature of the
atmosphere ‘in the beginning,’ we needed to determine what gas species were in
the magmas supplying the atmosphere.”
As magma approaches the Earth’s surface, it either erupts or stalls in
the crust, where it interacts with surrounding rocks, cools, and crystallizes
into solid rock. These frozen magmas and the elements they contain can be
literal milestones in the history of Earth.
One important milestone is zircon. Unlike other materials that are
destroyed over time by erosion and subduction, certain zircons are nearly as
old as the Earth itself. As such, zircons can literally tell the entire history
of the planet – if you know the right questions to ask.
The scientists sought to determine the oxidation levels of the magmas
that formed these ancient zircons to quantify, for the first time ever, how
oxidized were the gases being released early in Earth’s history. Understanding
the level of oxidation could spell the difference between nasty swamp gas and
the mixture of water vapor and carbon dioxide we are currently so accustomed
to, according to study lead author DustinTrail, a postdoctoral
researcher in the Center for Astrobiology.
“By determining the oxidation state of the magmas that created zircon,
we could then determine the types of gases that would eventually make their way
into the atmosphere,” said Trail.
To do this Trail, Watson, and their colleague, postdoctoral researcher
Nicholas Tailby, recreated the formation of zircons in the laboratory at
different oxidation levels. They literally created lava in the lab. This
procedure led to the creation of an oxidation gauge that could then be compared
with the natural zircons.
During this process they looked for concentrations of a rare Earth
metal called cerium in the zircons. Cerium is an important oxidation gauge because
it can be found in two oxidation states, with one more oxidized than the other.
The higher the concentrations of the more oxidized type cerium in zircon, the
more oxidized the atmosphere likely was after their formation.
The calibrations reveal an atmosphere with an oxidation state closer to
present-day conditions. The findings provide an important starting point for
future research on the origins of life on Earth.
“Our planet is the stage on which all of life has played out,” Watson
said. “We can’t even begin to talk about life on Earth until we know what that
stage is. And oxygen conditions were vitally important because of how they
affect the types of organic molecules that can be formed.”
Despite being the atmosphere that life currently breathes, lives, and
thrives on, our current oxidized atmosphere is not currently understood to be a
great starting point for life. Methane and its oxygen-poor counterparts have
much more biologic potential to jump from inorganic compounds to
life-supporting amino acids and DNA. As such, Watson thinks the discovery of
his group may reinvigorate theories that perhaps those building blocks for life
were not created on Earth, but delivered from elsewhere in the galaxy.
The results do not, however, run contrary to existing theories on
life’s journey from anaerobic to aerobic organisms. The results quantify the
nature of gas molecules containing carbon, hydrogen, and sulfur in the earliest
atmosphere, but they shed no light on the much later rise of free oxygen in the
air. There was still a significant amount of time for oxygen to build up in the
atmosphere through biologic mechanisms, according to Trail.
The New YorkCenter for Astrobiology
Based within the School of Science at Rensselaer Polytechnic Institute in Troy, N.Y., the New YorkCenter for Astrobiology is devoted to
investigating the origins of life on Earth and the conditions that lead to
formation of habitable planets in our own and other solar systems. Supported by
NASA, the $7 million center is a member of NASA’s Astrobiology Institute (NAI),
and is a partnership between Rensselaer and the University at Albany,
the University of Arizona, and the University of North Dakota.
Researchers and students within the center seek to understand the chemical,
physical, and geological conditions of early Earth that set the stage for life
on our planet. They also look beyond our home planet to investigate whether the
processes that prepared the Earth for life could be replicated elsewhere — on
Mars and other bodies in our solar system, for example, and on planets orbiting