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Cassini Finds Titan Lake is Like a Namibia Mudflat

By Guest PostApril 20, 2012Scienceatmosphere, bonnie buratti, cassini spacecraft, earth, ethane, etosha salt pan, geological feature, groundwater level, hydrocarbon cycle, lake, liquid hydrocarbon, methane, moon, mudflats, NASA, ontario lacus, propane, rainy season, saturated sand, saturn, south polar, thomas cornet, titan

A new study analyzing data from NASA’s Cassini spacecraft suggests that the lake, known as Ontario Lacus, behaves most similarly to what we call a salt pan on Earth.

A group led by Thomas Cornet of the Université de Nantes, France, a Cassini associate, found evidence for long-standing channels etched into the lake bed within the southern boundary of the depression. This suggests that Ontario Lacus, previously thought to be completely filled with liquid hydrocarbons, could actually be a depression that drains and refills from below, exposing liquid areas ringed by materials like saturated sand or mudflats. (more…)

Cosmic Ray Mystery

By Guest PostApril 19, 2012Scienceactive galaxies, Antarctica, array of detector, australia, bakhtiyar ruzybayev, barbados, belgium, black hole, canada, charged particle, chris elliott, cosmic ray, cosmic ray protons, data, density of radiation, detector, earth, energy, fermi satellites, fireballs, francis halzen, gamma ray bursts, Germany, ghostly nature, glacial ice, grbs, greg sullivan, icecube, icetop, james roth, Japan, katie shirey, NASA, national science foundation, neutrinos, new zealand, nsf, production, proton, pyramid of giza, south pole, Sweden, swift, switzerland, telescope, thomas gaisser, universe, university of delaware, university of wisconsin, US

Massive detector homes in on cosmic ray production

IceCube, an international collaboration involving University of Delaware scientists, is shedding new light on cosmic ray production.

Although cosmic rays were discovered 100 years ago, their origin remains one of the most enduring mysteries in physics. Now, the IceCube Neutrino Observatory, a massive detector in Antarctica, is homing in on how the highest energy cosmic rays are produced. (more…)

Space Weather Forecast: Sunspotty, With an Increasing Chance of Solar Storms

By Guest PostApril 15, 2012Environmentatmosphere, coronal mass ejections, dark sky, earth, flagpole, fm broadcasts, forecast, frank lind, gps, john sahr, k p index, kuow, laura vertatschitsch, magnetic field, magnetosphere, mars, mary levin, mechanical energy, molecular plasma, northern light, satellites, seattle, sieg hall, solar flares, solar storms, source, space weather, sunspot cycle, sunspotty, transmitter, xray

The past few months have seen a spate of solar flares – bringing spectacular views of the northern lights as far south as Seattle – along with media speculation that the electrical activity could disrupt power grids, satellites or ground airplanes.

John Sahr, a UW professor of electrical engineering who studies the upper atmosphere, is the regional go-to guy for such questions. We found some time in Sahr’s busy schedule (he’s also the UW’s associate dean of undergraduate academic affairs and a part-time zombie hunter) to get his read on the space weather forecast. (more…)

Newfangled Space-Propulsion Technology Could Help Clean up Earth Orbit

By Guest PostApril 12, 2012Scienceatmosphere, dead satellite, debris, earth, earth orbit, geosynchronous orbit, humans, international space station, mag beam, magnetized beam, magnetized ion plasma, mars, planet, plasma propulsion device, real estate, robert winglee, space junk, spacecraft, system, ultra high speed

Some of the most valuable “real estate” for humans isn’t on Earth at all but rather above the planet’s atmosphere, where all manner of human-made objects orbit. The problem is that those orbits are too crowded with dead satellites and debris, making new launches riskier.

Robert Winglee has spent years developing a magnetized ion plasma system to propel a spacecraft at ultra-high speeds, making it possible to travel to Mars and return to Earth in as little time as 90 days. The problem is that cost and other issues have dampened the desire to send astronauts to Mars or any other planet. (more…)

Thawing Permafrost 50 Million Years Ago Led To Warm Global Events, Says New Study

By Guest PostApril 7, 2012EnvironmentAntarctica, arctic permafrost, carbon, climate, climatic threshold, CO2, earth, eccentric orbits, ecosystem, Environment, floor sediment, fossil fuel, frozen-soil, greenhouse gas levels, italy, kevin schaefer, methane gas, ocean, orbit, organic matter, paleocene eocene, permafrost, permafrost thaw, petm, rob deconto, soil, source, thermal maximum, university of urbino

A new study led by the University of Massachusetts Amherst and involving the University of Colorado Boulder proposes a simple new mechanism to explain the source of carbon that fed a series of extreme warming events on Earth about 50 million years ago called the Paleocene-Eocene Thermal Maximum, or PETM, as well as a sequence of similar, smaller warming events afterward.

“The standard hypothesis has been that the source of carbon was in the ocean in the form of frozen methane gas in ocean-floor sediments,” said lead study author Rob DeConto of the University of Massachusetts Amherst. “We are instead ascribing the carbon source to the continents in polar latitudes where permafrost can store massive amounts of carbon that can be released as CO2 when the permafrost thaws.” (more…)

12-Mile-High Martian Dust Devil Caught in Act

By Guest PostApril 6, 2012Scienceamazonis planitia, dust devil, earth, hirise camera, mars reconnaissance orbiter, martian dust devil, martian surface, meteorite impact, NASA, northern mars, northern summer solstice, plume, red planet, tucson, university of arizona

A Martian dust devil roughly 12 miles high (20 kilometers) was captured whirling its way along the Amazonis Planitia region of Northern Mars on March 14. It was imaged by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. Despite its height, the plume is little more than three-quarters of a football field wide (70 yards, or 70 meters).

Dust devils occur on Earth as well as on Mars. They are spinning columns of air, made visible by the dust they pull off the ground. Unlike a tornado, a dust devil typically forms on a clear day when the ground is heated by the sun, warming the air just above the ground. As heated air near the surface rises quickly through a small pocket of cooler air above it, the air may begin to rotate, if conditions are just right. (more…)

New Understanding of Earth’s Mantle Beneath The Pacific Ocean

By Guest PostMarch 24, 2012Scienceasthenosphere, boundary, carnegie, crust, earth, evolution, factors, gutenberg discontinuity, lab, lithosphere, lithosphere asthenosphere boundary, mineral, molten rock, nick schmerr, pacific ocean basin, planet, plate tectonics

Washington, D.C. — Scientists have long speculated about why there is a large change in the strength of rocks that lie at the boundary between two layers immediately under Earth’s crust: the lithosphere and underlying asthenosphere. Understanding this boundary is central to our knowledge of plate tectonics and thus the formation and evolution of our planet as we know it today. A new technique for observing this transition, particularly in the portion of Earth’s mantle that lies beneath the Pacific Ocean basin, has led Carnegie and NASA Goddard scientist Nick Schmerr to new insight on the origins of the lithosphere and asthenosphere. His work is published March 23 in Science.

The lithosphere-asthenosphere boundary, or LAB, represents the transition from hot, convecting mantle asthenosphere to overlying cold and rigid lithosphere. The oceanic lithosphere thickens as it cools over time, and eventually sinks back into the mantle at Earth’s so-called subduction zones. (more…)

Study of Patagonian Glacier’s Rise and Fall Adds to Understanding of Global Climate Change

By Guest PostMarch 24, 2012Environment17th century, andes, antonio de vea, chilean glacier, climate, climate change, climate system, earth, fernando torrejon, fluctuation, glacial environment, glacial melt, glacier, glacier fluctuation, glaciomarine sediment, global temperature, golfo elefantes, gualas glacier, holocene glacier, icebreaker, marine environment, nathaniel b palmer, neoglacial fluctuation, northern patagonian icefield, past temperature, patagonia, patagonias fjords, rainfall data, san rafael, sebastien bertrand, sediment record, spanish explorers, university of ghent, voyages, whoi

Glaciers play a vital role in Earth’s climate system, and it’s critical to understand what contributes to their fluctuation.

Increased global temperatures are frequently viewed as the cause of glacial melt, but a new study of Patagonia’s Gualas Glacier highlights the role of precipitation in the glacier’s fluctuation. The study, conducted by Sébastien Bertrand of the Woods Hole Oceanographic Institution (WHOI) and his colleagues, reconstructs a 5,400 year-record of the region’s glacial environment and climate, comparing past temperature and rainfall data with sediment records of glacier fluctuations and the historical observations of early Spanish explorers. (more…)

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