earth – Page 15 – Shamskm: A site to exchange knowledge and solutions

Freezing Electrons in Flight

By Guest PostOctober 13, 2012Science1878, arizona, artificial, arvinder sandhu, atmosphere, atom, attosecond, camera, chemical process, destruction, eadweard muybridge, earth, electron, electron emission, electronic devices, electronic motion, emulsion plate, excited atom, femtosecond, formation, ground, henry timmers, high energy, horse, iconic series, laser flash, laser pulses, microscopic dynamics, molecular process, muybridge, mystery, natural, niranjan shivaram, oxygen molecule, ozone, phenomena, photo, photograph, physical, quintillionths, real-time, second, stroboscopy, super excited, technique, touch, ultrafast, ultraviolet light, university, upper atmosphere, zeptosecond

Using the world’s fastest laser pulses, which can freeze the ultrafast motion of electrons and atoms, UA physicists have caught the action of molecules breaking apart and electrons getting knocked out of atoms. Their research helps us better understand molecular processes and ultimately be able to control them in many possible applications.

In 1878, a now iconic series of photographs instantly solved a long-standing mystery: Does a galloping horse touch the ground at all times? (It doesn’t.) The images of Eadweard Muybridge taken alongside a racetrack marked the beginning of high-speed photography.

Approximately 134 years later, researchers in the University of Arizona department of physics have solved a similar mystery, one in which super-excited oxygen molecules have replaced the horse, and ultrafast, high-energy laser flashes have replaced Muybridge’s photo emulsion plates. (more…)

Bounce, Skid, Wobble: How Huygens Landed on Titan

By Guest PostOctober 11, 2012Science17th century, analysis, astronomer, cassini spacecraft, christiaan huygens, direction, dutch, earth, erich karkoschka, european, evaporate, friction, hazy atmosphere, horizon, huygens data, huygens impact, huygens probe, institute, lower atmosphere, max planck, methane, model, moon, moon surface, motion, mud like, NASA, nicolas altobelli, organic aerosols, ralph lorenz, saturn, space agency, splat, stefan schroder, substance, titan, titan atmosphere, undisturbed terrain

Piecing together the events of the farthest touchdown a manmade spacecraft has ever made on an alien world reveals new clues about Titan’s surface and helps plan future missions to moons and planets.

The Huygens probe, ferried to Saturn’s moon Titan by NASA’s Cassini spacecraft, bounced, slid and wobbled its way to rest in the 10 seconds after touching down on Titan in January 2005, a new analysis reveals. The moon’s surface is more complex than previously thought.

Scientists reconstructed the chain of events by analyzing data from a variety of instruments that were active during the impact, in particular changes in the acceleration experienced by the probe. The probe was supplied by the European Space Agency and named after the Dutch 17th century astronomer Christiaan Huygens. (more…)

Scientists Uncover Vast Differences in Earth’s Polar Ocean Microbial Communities

By Guest PostOctober 10, 2012Environmentalison murray, Antarctica, arctic ocean, biodiversity, biodiversity pattern, biogeographically, canada, changing climate, coast, community, continental, drainage basin, earth, environmental selection, flow, france, freshwater, glacial melt, global ocean, jean françois ghiglione, kevin bakker, marine, marine life, marine microbe, michigan, microbial community, microbial diversity, new zealand, ocean, oceanic circulation, oden, polar ocean, polar region, polar year, pole, sea ice, sloan foundation, southern, spain, structure, Sweden, swedish icebreaker, united states, university

ANN ARBOR— An international team of scientists, including a University of Michigan graduate student, has demonstrated that a clear difference exists between the marine microbial communities in the Southern and Arctic oceans, contributing to a better understanding of the biodiversity of marine life at the poles.

The most comprehensive comparison of microbial diversity at both of Earth’s polar oceans showed that about 75 percent of the organisms at each pole are different. This insight sheds light on newly recognized biodiversity patterns and reinforces the importance of studying Earth’s polar regions in the face of a changing climate. And it highlights the need for further research on the impacts of sea ice, seasonal shifts and freshwater input in both regions. (more…)

Technology in the Classroom

By Guest PostOctober 5, 2012Educationclassroom, clickers, delaware, earth, geological hazards, geological sciences, geological topics, hollywood, misconceptions, molten liquid, plate tectonics, susan mcgeary, Technology, ud capture, university, video, virginia earthquake

A professor uses clickers and UD Capture to make a large class feel smaller

Susan McGeary, associate professor in the Department of Geological Sciences at the University of Delaware, incorporated clickers and UD Capture for the first time in spring 2012 to see if she could increase student participation. What McGeary did not expect was the level of engagement in her Geological Hazards course, which is a 250-300 person class.

“Clickers seemed to remove the barrier between me and the students; they approached me more, asked more questions, were more involved during the class — it was exciting,” McGeary said. (more…)

Researchers Highlight Growing Problem of Ocean Acidification

By Guest PostSeptember 27, 2012Environmentatmosphere, carbon biogeochemistry, carbon dioxide, CO2, co2 conditions, co2 world, earth, emission, eucidaris tribuloides, faq, global issue, hole, institution, logarithmic, monterey, neutral, oa, ocb, ocean, ocean acidification, oceanographic, pencil urchins, ph, ph scale, ph unit, sarah cooley, tropical, web version, whoi, woods

An international group of scientists, including researchers from the Woods Hole Oceanographic Institution, are working to improve communication about ocean acidification to help the public better understand the pressing global issue.

The term “ocean acidification” (OA) describes the changes that occur in the ocean as a result of increased emissions of carbon dioxide (CO₂) into the atmosphere. The rising acidic level in the ocean puts certain organisms at risk and threatens the overall health of the ocean. (more…)

Large Bacterial Population Colonized Land 2.75 Billion Years Ago

By Guest PostSeptember 26, 2012Scienceatmosphere, atmospheric oxygenation, cambrian period, continental rock, data, database, david catling, earth, Environment, eva stueken, event, geologist, great, methane, microbial life, molybdenum, ocean, oxidation, oxygen, ozone layer, research record, roger buick, sulfur, ultraviolet radiation, university, Washington, weathering pyrite

There is evidence that some microbial life had migrated from the Earth’s oceans to land by 2.75 billion years ago, though many scientists believe such land-based life was limited because the ozone layer that shields against ultraviolet radiation did not form until hundreds of millions years later.

But new research from the University of Washington suggests that early microbes might have been widespread on land, producing oxygen and weathering pyrite, an iron sulfide mineral, which released sulfur and molybdenum into the oceans. (more…)

World’s Most Powerful Digital Camera Begins Hunt for Dark Energy

By Guest PostSeptember 22, 2012Scienceancient starlight, atmospheric condition, billion years, brazil, brenna flaugher, camera, cerro tololo, Chicago, Chile, chilean andes, chris smith, dark energy, des, distant galaxy, earth, expansion, fermilab, galaxy cluster, Germany, gravitational lensing, inter american, james siegrist, kavli institute, mystery, ngc 1365, noao, observatory, physics, southern sky, spain, spiral galaxy, switzerland, telescope, united kingdom, universe, university, victor m blanco

Eight billion years ago, rays of light from distant galaxies began their long journey to Earth. That ancient starlight has now found its way to a mountaintop in Chile, where the newly constructed Dark Energy Camera, the most powerful sky-mapping machine ever created, has captured and recorded it for the first time.

That light may hold within it the answer to one of the biggest mysteries in physics: Why the expansion of the universe is speeding up. (more…)

Dinosaur Die Out Might Have Been Second of Two Closely Timed Extinctions

By Guest PostSeptember 6, 2012Scienceaerosols, ammonite, antarctic peninsula, antarctic sediment, Argentina, asteroid, asteroid impact, carbon dioxide, deccan plateau, dinosaurs, earth, eduardo olivero, environmental effect, eric steig, fossil, free swimming, greenhouse gas, hell creek formation, history, India, isaac hilburn, james ross island, joseph kirschvink, magnetic field, magnetostratigraphy, mass extinction, matthew diamond, Mexico, montana, ocean floor, particles, peter ward, planet, ross mitchell, second event, sediment deposit, seymour island, species, thomas tobin, timothy raub, university, volcanic eruption, Washington, yale university, yucatan peninsula

The most-studied mass extinction in Earth history happened 65 million years ago and is widely thought to have wiped out the dinosaurs. New University of Washington research indicates that a separate extinction came shortly before that, triggered by volcanic eruptions that warmed the planet and killed life on the ocean floor.

The well-known second event is believed to have been triggered by an asteroid at least 6 miles in diameter slamming into Mexico’s Yucatán Peninsula. But new evidence shows that by the time of the asteroid impact, life on the seafloor – mostly species of clams and snails – was already perishing because of the effects of huge volcanic eruptions on the Deccan Plateau in what is now India. (more…)

Tag Archives: earth