Dead Or Alive Mars Pumps Methane

•January 17, 2009 • Leave a Comment

Mars today is a world of cold and lonely deserts, apparently without life of any kind, at least on the surface. Worse still, it looks like Mars has been cold and dry for billions of years, with an atmosphere so thin, any liquid water on the surface quickly boils away while the sun’s ultraviolet radiation scorches the ground.

But there is evidence of a warmer and wetter past – features resembling dry riverbeds and minerals that form in the presence of water indicate water once flowed through Martian sands. Since liquid water is required for all known forms of life, scientists wonder if life could have risen on Mars, and if it did, what became of it as the Martian climate changed.

New research reveals there is hope for Mars yet. The first definitive detection of methane in the atmosphere of Mars indicates the planet is still alive, in either a biologic or geologic sense, according to a team of NASA and university scientists.

“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 – four atoms of hydrogen bound to a carbon atom – is the main component of natural gas on Earth. It’s of interest to astrobiologists because organisms release much of Earth’s methane as they digest nutrients. However, other purely geological processes, like oxidation of iron, also release methane.

“Right now, we don’t have enough information to tell if biology or geology – or both – is producing the methane on Mars,” said Mumma.

“But it does tell us that the planet is still alive, at least in a geologic sense. It’s as if Mars is challenging us, saying, hey, find out what this means.” Mumma is lead author of a paper on this research appearing in Science Express Jan. 15.

If microscopic Martian life is producing the methane, it likely resides far below the surface, where it’s still warm enough for liquid water to exist. Liquid water, as well as energy sources and a supply of carbon, are necessary for all known forms of life.

“On Earth, microorganisms thrive 2 to 3 kilometers (about 1.2 to 1.9 miles) beneath the Witwatersrand basin of South Africa, where natural radioactivity splits water molecules into molecular hydrogen (H2) and oxygen.

The organisms use the hydrogen for energy. It might be possible for similar organisms to survive for billions of years below the permafrost layer on Mars, where water is liquid, radiation supplies energy, and carbon dioxide provides carbon,” said Mumma.

“Gases, like methane, accumulated in such underground zones might be released into the atmosphere if pores or fissures open during the warm seasons, connecting the deep zones to the atmosphere at crater walls or canyons,” said Mumma.

“Microbes that produced methane from hydrogen and carbon dioxide were one of the earliest forms of life on Earth,” noted Dr. Carl Pilcher, Director of the NASA Astrobiology Institute which partially supported the research.

“If life ever existed on Mars, it’s reasonable to think that its metabolism might have involved making methane from Martian atmospheric carbon dioxide.”

However, it is possible a geologic process produced the Martian methane, either now or eons ago. On Earth, the conversion of iron oxide (rust) into the serpentine group of minerals creates methane, and on Mars this process could proceed using water, carbon dioxide, and the planet’s internal heat. Although we don’t have evidence on Mars of active volcanoes today, ancient methane trapped in ice “cages” called clathrates might now be released.

The team found methane in the atmosphere of Mars by carefully observing the planet over several Mars years (and all Martian seasons) with NASA’s Infrared Telescope Facility, run by the University of Hawaii, and the W. M. Keck telescope, both at Mauna Kea, Hawaii.

The team used spectrometer instruments attached to the telescopes to make the detection. Spectrometers spread light into its component colors, like a prism separates white light into a rainbow.

The team looked for dark areas in specific places along the rainbow (light spectrum) where methane was absorbing sunlight reflected from the Martian surface.

They found three such areas, called absorption lines, which together are a definitive signature of methane, according to the team.

They were able to distinguish lines from Martian methane from the methane in Earth’s atmosphere because the motion of the Red Planet shifted the position of the Martian lines, much as a speeding ambulance causes its siren to change pitch as it passes by.

“We observed and mapped multiple plumes of methane on Mars, one of which released about 19,000 metric tons of methane,” said Dr. Geronimo Villanueva of the Catholic University of America, Washington, D.C. Villanueva is stationed at NASA Goddard and is co-author of the paper.

“The plumes were emitted during the warmer seasons – spring and summer – perhaps because the permafrost blocking cracks and fissures vaporized, allowing methane to seep into the Martian air. Curiously, some plumes had water vapor while others did not,” said Villanueva.

According to the team, the plumes were seen over areas that show evidence of ancient ground ice or flowing water. For example, plumes appeared over northern hemisphere regions such as east of Arabia Terra, the Nili Fossae region, and the south-east quadrant of Syrtis Major, an ancient volcano 1,200 kilometers (about 745 miles) across.

It will take future missions, like NASA’s Mars Science Laboratory, to discover the origin of the Martian methane. One way to tell if life is the source of the gas is by measuring isotope ratios. Isotopes are heavier versions of an element; for example, deuterium is a heavier version of hydrogen. In molecules that contain hydrogen, like water and methane, the rare deuterium occasionally replaces a hydrogen atom.

Since life prefers to use the lighter isotopes, if the methane has less deuterium than the water released with it on Mars, it’s a sign that life is producing the methane. The research was funded by NASA’s Planetary Astronomy Program and the NASA Astrobiology Institute.

Cooling The Planet By Growing The Right Crops

•January 17, 2009 • Leave a Comment

By carefully selecting which varieties of food crops to cultivate, much of Europe and North America could be cooled by up to 1°C during the summer growing season, say researchers from the University of Bristol, UK. This is equivalent to an annual global cooling of over 0.1°C, almost 20% of the total global temperature increase since the Industrial Revolution.
The growing of crops already produces a cooling of the climate because they reflect more sunlight back into space, compared with natural vegetation. Different varieties of the same crop vary significantly in their solar reflectivity (called ‘albedo’), so selecting varieties that are more reflective will enhance this cooling effect. Since arable agriculture is a global industry, such cooling could be extensive.

Dr Andy Ridgwell and colleagues at the University of Bristol argue that we should select crop varieties in order to exert a control on the climate, in the same way that we currently cultivate specific varieties to maximize and fine-tune food production.

Dr Ridgwell said: “We have evaluated the effect of our approach in a global climate model. By choosing from among current crop varieties, our best estimate for how much reflectivity might be increased leads us to predict that summer-time temperatures could be reduced by more than 1°C throughout much of central North America and mid-latitude Eurasia. Ultimately, further regional cooling of the climate could be made through selective breeding or genetic modification to optimise crop plant albedo.”

The team emphasised that unlike growing biofuels, such a plan could be achieved without disrupting food production, either in terms of yield or the types of crops grown. “We propose choosing between different varieties of the same crop species in order to maximize solar reflectivity rather than changing crop type, although the latter could also produce climatic benefits,” explained Ridgwell.

Over the next hundred years, making these kinds of decisions would be equivalent to averting the carbon footprint of 195 billion tonnes of CO2 emitted into the atmosphere. Farmers could be encouraged to grow such crops by issuing them with carbon credits. Ridgwell has calculated that if such a mechanism were in place farmers might expect to earn in the region of 23 euros per hectare per year for the warming averted. Biofuels currently earn 45 euros per hectare per year, but take up valuable agricultural land needed for growing crops.

Plants differ in their albedo because of differences in the properties of the leaf’s surface and how the leaves are arranged (called ‘canopy morphology’). The team therefore propose that the varieties grown should be chosen for their reflective properties alongside other considerations already made when planting crops, such as the food processing characteristics of a grain.

Since society has so far remained unwilling to make the drastic reductions in fossil fuel use needed to cut carbon dioxide emissions, simple alternatives such as growing more reflective crops are a realistic way of helping reduce the severity of heat waves and droughts in these regions. Results could be achieved very quickly and at very little cost.

“There is a clear need for more research into characterising the variability in albedo that currently exists between the different variants and strains of common crop plants,” commented Ridgwell. “We are applying for funding that will enable us to better quantify what is possible now, what variability there is for future selective breeding, and whether there is a need for genetic modification in the future”.

Arctic Heats Up More Than Other Places: High Sea Level Rise Predicted

•January 17, 2009 • Leave a Comment

Temperature change in the Arctic is happening at a greater rate than other places in the Northern Hemisphere, and this is expected to continue in the future.
As a result, glacier and ice-sheet melting, sea-ice retreat, coastal erosion and sea level rise can be expected to continue.

A new comprehensive scientific synthesis of past Arctic climates demonstrates for the first time the pervasive nature of Arctic climate amplification.

The U.S. Geological Survey led this new assessment, which is a synthesis of published science literature and authored by a team of climate scientists from academia and government. The U.S. Climate Change Science Program commissioned the report, which has contributions from 37 scientists from the United States, Germany, Canada, the United Kingdom and Denmark.

The new report also makes several conclusions about the Arctic:

* Taken together, the size and speed of the summer sea-ice loss over the last few decades is highly unusual compared to events from previous thousands of years, especially considering that changes in Earth’s orbit over this time have made sea-ice melting less, not more, likely.
* Sustained warming of at least a few degrees (more than approximately 4° to 13°F above average 20th century values) is likely to be sufficient to cause the nearly complete, eventual disappearance of the Greenland ice sheet, which would raise sea level by several meters.
* The current rate of human-influenced Arctic warming is comparable to peak natural rates documented by reconstructions of past climates. However, some projections of future human-induced change exceed documented natural variability.
* The past tells us that when thresholds in the climate system are crossed, climate change can be very large and very fast. We cannot rule out that human induced climate change will trigger such events in the future.

“By integrating research on the past 65 million years of climate change in the entire circum-Arctic, we have a better understanding on how climate change affects the Arctic and how those effects may impact the whole globe,” said USGS Director Mark Myers. “This report provides the first comprehensive analysis of the real data we have on past climate conditions in the Arctic, with measurements from ice cores, sediments and other Earth materials that record temperature and other conditions.”

Hazards Of Severe Space Weather Revealed

•January 17, 2009 • 1 Comment

A NASA-funded study describes how extreme solar eruptions could have severe consequences for communications, power grids and other technology on Earth.
The National Academy of Sciences in Washington conducted the study. The resulting report provides some of the first clear economic data that effectively quantifies today’s risk of extreme conditions in space driven by magnetic activity on the sun and disturbances in the near-Earth environment. Instances of extreme space weather are rare and are categorized with other natural hazards that have a low frequency but high consequences.

“Obviously, the sun is Earth’s life blood,” said Richard Fisher, director of the Heliophysics division at NASA Headquarters in Washington. “To mitigate possible public safety issues, it is vital that we better understand extreme space weather events caused by the sun’s activity.”

Besides emitting a continuous stream of plasma called the solar wind, the sun periodically releases billions of tons of matter called coronal mass ejections. These immense clouds of material, when directed toward Earth, can cause large magnetic storms in the magnetosphere and upper atmosphere. Such space weather can affect the performance and reliability of space-borne and ground-based technological systems.

Space weather can produce solar storm electromagnetic fields that induce extreme currents in wires, disrupting power lines, causing wide-spread blackouts and affecting communication cables that support the Internet. Severe space weather also produces solar energetic particles and the dislocation of the Earth’s radiation belts, which can damage satellites used for commercial communications, global positioning and weather forecasting. Space weather has been recognized as causing problems with new technology since the invention of the telegraph in the 19th century.

A catastrophic failure of commercial and government infrastructure in space and on the ground can be mitigated through raising public awareness, improving vulnerable infrastructure and developing advanced forecasting capabilities. Without preventive actions or plans, the trend of increased dependency on modern space-weather sensitive assets could make society more vulnerable in the future.

NASA requested the study to assess the potential damage from significant space weather during the next 20 years. National and international experts from industry, government and academia participated in the study. The report documents the possibility of a space weather event that has societal effects and causes damage similar to natural disasters on Earth.

“From a public policy perspective, it is quite significant that we have begun the extremely challenging task of assessing space weather impacts in a quantitative way,” said Daniel Baker, professor and director of the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder. Baker chaired the panel that prepared the report.

“Whether it is terrestrial catastrophes or extreme space weather incidents, the results can be devastating to modern societies that depend in a myriad of ways on advanced technological systems,” said Baker. “We were delighted that NASA helped support bringing together dozens of world experts from industry and government to share their experiences and begin planning of improved public policy strategies.”

The sun is currently near the minimum of its 11-year activity cycle. It is expected that solar storms will increase in frequency and intensity toward the next solar maximum, expected to occur around 2012.

The Heliophysics Division of NASA’s Science Mission Directorate in Washington provided funding for the study. The division seeks to understand the sun, its solar processes and the interaction of solar plasma and radiation with Earth, other planets and the universe. Understanding the connections between the sun and its planets will allow better prediction on the impacts of solar activity on humans, technological systems and even the presence of life itself in the universe.

The National Academies are chartered by Congress to provide independent technical and scientific advice to the federal government.

Eclipse to darken NW China, a week before Olympics

•August 2, 2008 • 1 Comment

JIAYUGUAN, China (Reuters) – A full solar eclipse will sweep across the Arctic and Siberia before ending in western China, where it will kick off the month in which Beijing hosts the Olympic Games.

The eclipse was due to begin in Canada at 0804 GMT, track across Greenland and eastern Russia and end around sunset on Friday to the east of Xi’an, China‘s ancient imperial capital.

Eclipses were dangerous omens for ancient Chinese astronomers, but this one comes exactly a week before the torch is lit in Beijing for the opening ceremony of Games designed to restore China’s pride and showcase its achievements.

Planeloads of cheerful foreign eclipse chasers converged on Jiayuguan, in Gansu Province, and in the hot deserts of Xinjiang, to watch the sky go dark and a halo wreathe the hidden sun.

“I’ve come all the way from California for this. It’s going to be my 11th eclipse, I try to see them all,” said Dave Balch, a cancer care advisor wearing an eclipse T-shirt.

Scientists studying the sun’s surface prepared for a brief glimpse of the faint outer corona that is normally obscured by the sun’s brightness.

“Nowadays, the equipment works well enough that we do have time to look up at the eclipse,” said Jay Pasachoff, a professor at Williams College who traveled to Novosibirsk, Russia for his 47th eclipse.

“It’s very dramatic and awe-inspiring when the darkness suddenly comes. That’s why thousands of tourists go to see.”

Hundreds of millions of people won’t have to go any further than their front doors on July 22, 2009, when the next solar eclipse will cross India and northern Bangladesh, then run along the Yangtze River from Chongqing to Shanghai in the most populated path ever.

OMEN

Chinese hope that the Olympics will usher in a new era where China is once more as modern, wealthy and important as it was more than 10 centuries ago, when imperial astronomers were among the world’s best scientists and camel caravans carried riches along the pass guarded by Jiayuguan.

Chinese astronomers in the state of Lu, present day Shandong, carefully recorded solar eclipses that can be dated as far back as 720 BC. Earlier than that, inscriptions on oracle bones asked what eclipses might portend.

Eclipses were sometimes linked to the subsequent deaths of emperors and empresses, said F. Richard Stephenson, professor emeritus at Durham University in northern England.

Chinese astronomers understood what caused eclipses and could predict them very accurately by AD 300, but superstitious courtiers and peasants still banged drums to scare away the dragon they thought was eating the sun.

People still find their lives can be touched by eclipses, but the modern view is a little more philosophic.

“I was born during an eclipse, and I have always felt that’s made my life more fortunate,” said a driver named Zhou. “But I didn’t turn out to have any special genius, so I can’t say the eclipse left any mark of fate or destiny on me.”

source: http://news.yahoo.com/s/nm/20080801/sc_nm/eclipse_dc;_ylt=AuvYTvTtjfxb7Srhpx39VHWHgsgF

Top Ten Unexplained Phenomena

•August 2, 2008 • 3 Comments

The Body/Mind Connection

Medical science is only beginning to understand the ways in which the mind influences the body. The placebo effect, for example, demonstrates that people can at times cause a relief in medical symptoms or suffering by believing the cures to be effective – whether they actually are or not. Using processes only poorly understood, the body’s ability to heal itself is far more amazing than anything modern medicine could create.

Psychic powers and ESP

Psychic powers and extra-sensory perception (ESP) rank among the top ten unexplained phenomena if for no other reason than that belief in them is so widespread. Many people believe that intuition (see #3) is a form of psychic power, a way of accessing arcane or special knowledge about the world or the future. Researchers have tested people who claim to have psychic powers, though the results under controlled scientific conditions have so far been negative or ambiguous. Some have argued that psychic powers cannot be tested, or for some reason diminish in the presence of skeptics or scientists. If this is true, science will never be able to prove or disprove the existence of psychic powers.

Continue reading ‘Top Ten Unexplained Phenomena’

Unique Habitat Found Inside Earth

•August 2, 2008 • 2 Comments

The star-shaped bacterium was isolated from mine-slime, 1.7 km below the surface. The ruler shown for scale is in centimetres.

The cell membrane of the bacterium twists and turns to provide its unique shape.

Researchers studying life in the deep subsurface of our planet have discovered a unique bacterium living 1 mile (1.7 km) below the Earth’s surface. The tiny bacteria live in a community of subsurface microbes inhabiting a South African platinum mine.

Continue reading ‘Unique Habitat Found Inside Earth’

 
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