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The Flowing Sands of Mars

By Guest PostMay 13, 2012ScienceAntarctica, caltech, craters, digital terrain model, doug mccuistion, dtm, earth, flowing sands, geological processes, gullies, high speed winds, hirise camera, jean philippe avouac, mars, martian equator, martian landscape, martian surface, mro, NASA, nathan bridges, nili patera, red planet, rocks on mars, sand dunes, sarah mattson, valleys

Sand dunes on Mars move not unlike those on Earth, despite a much thinner atmosphere and weaker winds, as revealed by images taken with the UA-led HiRISE camera.

NASA’s Mars Reconnaissance Orbiter, or MRO, has revealed that movement in sand dune fields on the Red Planet occurs on a surprisingly large scale, about the same as in dune fields on Earth.

This is unexpected because Mars has a much thinner atmosphere than Earth is only about 1 percent as dense, and its high-speed winds are less frequent and weaker than Earth’s.

For years, researchers debated whether or not sand dunes observed on Mars were mostly fossil features related to past climate, rather than currently active. In the past two years, researchers using images from MRO’s High Resolution Imaging Science Experiment, or HiRISE, camera have detected and reported sand movement. (more…)

A NASA Weather ‘Eye in the Sky’ Marks 10 Years

By Guest PostMay 7, 2012Environment, Scienceairs, amsu a, atmosphere, atmospheric infrared sounder, bae systems, boston, carbon dioxide, climate change, climate research, earth, energy cycle, eric fetzer, eye, global water, greenhouse gases, hyperspectral sounding, instrument, jet propulsion laboratory, model, monster, moustafa chahine, NASA, sky, tom pagano, water vapor, weather forecasting, weather satellites

For 10 years, it has silently swooped through space in its orbital perch 438 miles (705 kilometers) above Earth, its nearly 2,400 spectral “eyes” peering into Earth’s atmosphere, watching. But there’s nothing alien about NASA’s Atmospheric Infrared Sounder, or AIRS, instrument, a “monster” of weather and climate research that celebrates its 10th birthday in orbit May 4.

AIRS, built by BAE Systems, Boston, under the direction of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., is one of six instruments flying on NASA’s Aqua spacecraft as part of NASA’s Earth Observing System. AIRS, along with its partner microwave instrument, the Advanced Microwave Sounding Unit (AMSU-A), has faithfully measured our planet’s atmospheric temperature, water vapor, clouds and greenhouse gases with unprecedented accuracy and stability. Over the past decade, AIRS and AMSU-A have improved our understanding of Earth’s global water and energy cycles, climate change and trends and how Earth’s climate system is responding to increased greenhouse gases. (more…)

NASA’s Spitzer Finds Galaxy with Split Personality

By Guest PostApril 27, 2012Sciencearchetypal galaxy, centaurus, Chile, constellation virgo, dimitri gadotti, earth, elliptical galaxy, ellipticals, Galaxy, galaxy evolution, globular cluster, NASA, ngc 4594, ruben sanchez janssen, sean carey, sombrero galaxy, spiral disk, spiral milky way, spitzer space telescope, split personality

PASADENA, Calif. — While some galaxies are rotund and others are slender disks like our spiral Milky Way, new observations from NASA’s Spitzer Space Telescope show that the Sombrero galaxy is both. The galaxy, which is a round elliptical galaxy with a thin disk embedded inside, is one of the first known to exhibit characteristics of the two different types. The findings will lead to a better understanding of galaxy evolution, a topic still poorly understood.

“The Sombrero is more complex than previously thought,” said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of a new paper on the findings appearing in the Monthly Notices of the Royal Astronomical Society. “The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other.” (more…)

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…)

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