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Measuring the Distant Universe in 3-D

By Guest PostMay 7, 2011Science3 d map, absorption, anže slosar, apache point observatory, bao, baryon acoustic oscillation, baryon oscillation, baryon oscillation spectroscopic survey, berkeley lab, bill carithers, BOSS, centers of galaxies, dark energy, david schlegel, james rich, lyman alpha forest, map intergalactic hydrogen gas, new mexico, of light years, precision tool, quasars, red galaxies, redshift, sdss, sloan digital sky survey, sloan telescope, spectrum, supermassive black holes, universe, wiggly structure

*Berkeley Lab-led BOSS proves it can do the job with quasars*

The biggest 3-D map of the distant universe ever made, using light from 14,000 quasars — supermassive black holes at the centers of galaxies many billions of light years away — has been constructed by scientists with the third Sloan Digital Sky Survey (SDSS-III).

The map is the first major result from the Baryon Oscillation Spectroscopic Survey (BOSS), SDSS-III’s largest survey, whose principal investigator is David Schlegel of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The huge new map was presented at the April meeting of the American Physical Society in Anaheim, CA, by Anže Slosar of Brookhaven National Laboratory. (more…)

Dawn Reaches Milestone Approaching Asteroid Vesta

By Guest PostMay 5, 2011Scienceasteroid, asteroid belt, asteroid vesta, cape canaveral air force station, celestial body, christopher russell, cosmic rays, dawn spacecraft, earth, earth orbiting telescopes, florida, gamma ray, interplanetary travel, marc rayman, NASA, neutron detector, orbit, planet, protoplanet, radio signal, spacecraft, terra incognita, vesta

PASADENA, Calif. — NASA’s Dawn spacecraft has reached its official approach phase to the asteroid Vesta and will begin using cameras for the first time to aid navigation for an expected July 16 orbital encounter. The large asteroid is known as a protoplanet — a celestial body that almost formed into a planet.

At the start of this three-month final approach to this massive body in the asteroid belt, Dawn is 1.21 million kilometers (752,000 miles) from Vesta, or about three times the distance between Earth and the moon. During the approach phase, the spacecraft’s main activity will be thrusting with a special, hyper-efficient ion engine that uses electricity to ionize and accelerate xenon. The 12-inch-wide ion thrusters provide less thrust than conventional engines, but will provide propulsion for years during the mission and provide far greater capability to change velocity. (more…)

Most Powerful Millimeter-Scale Energy Harvester Generates Electricity from Vibrations

By Guest PostMay 4, 2011Scienceconvert, energy harvester cyclic motions, harness energy, high-quality energy-harvesting piezoelectric material, intellectual property, novel silicon micromachining technique, ongoing life-cycle expenses of operating a wireless sensor, pervasive information-gathering sensor networks, sensors, solid-state, ultracapacitor, vibrations

ANN ARBOR, Mich.—Electrical engineers at the University of Michigan have built a device that can harness energy from vibrations and convert it to electricity with five to 10 times greater efficiency and power than other devices in its class. And it’s smaller than a penny.

“In a tiny amount of space, we’ve been able to make a device that generates more power for a given input than anything else out there on the market,” said Khalil Najafi, one of the system’s developers and chair of Electrical and Computer Engineering. (more…)

‘Ancient Bipedal Hominid Dubbed ‘Nutcracker Man’ Preferred Grass to Nuts’

By Guest PostMay 3, 2011Scienceafrican landscape, ancestors of humans, bipedal hominid, c3 photosynthetic, c4 photosynthetic pathway, carbon isotopes, emma mbua, hard fruit, hominid, huge molars, matt sponheimer, meave leakey, northern kenya, nutcracker man, nuts, paranthropus, paranthropus boisei, powerful jaws, savannah grasses, seeds, teeth, thure cerling, tropical environments, university of colorado boulder, zebras

An ancient, bipedal hominid sporting a set of powerful jaws and huge molars that earned it the nickname “Nutcracker Man” likely didn’t crack nuts at all, preferring instead to slurp up vast quantities of grasses and sedges, says a new study.

The hominid, known as Paranthropus boisei, ranged across the African landscape more than 1 million years ago and lived side-by-side with direct ancestors of humans, said University of Colorado Boulder anthropology Professor Matt Sponheimer, a study co-author. It was long assumed Paranthropus boisei favored nuts, seeds and hard fruit because of its huge jaws, powerful jaw muscles and the biggest and flattest molars of any known hominid in the anthropological record, he said. (more…)

Eddies Found to be Deep, Powerful Modes of Ocean Transport

By ShamsMay 1, 2011Environment, Scienceadams, computer models, deep sea phenomenon, deep-sea moorings, dennis j mcgillicuddy, diane k adams, east pacific rise, east scotia ridge, el niño, eruption, hydrothermal vents, indian ridge, jets, lauren s mullineaux, mid atlantic ridge, ocean, ocean bottom, ocean eddies, sea creatures, surface ocean dynamics, underwater mountain range, whoi, woods hole oceanographic institution

*Study Finds Connection between Atmospheric Events and the Deep Ocean*

Researchers from Woods Hole Oceanographic Institution (WHOI) and their colleagues have discovered that massive, swirling ocean eddies–known to be up to 500 kilometers across at the surface–can reach all the way to the ocean bottom at mid-ocean ridges, some 2,500 meters deep, transporting tiny sea creatures, chemicals, and heat from hydrothermal vents over large distances.

The previously unknown deep-sea phenomenon, reported in the April 28 issue of the journal Science, helps explain how some larvae travel huge distances from one vent area to another, said Diane K. Adams, lead author at WHOI and now at the National Institutes of Health. (more…)

Scorpion Venom – Bad for Bugs, Good for Pesticides

By Guest PostMay 1, 2011Sciencedesert scorpion, scorpion toxin project, scorpion toxins, scorpion venom

EAST LANSING, Mich. — Fables have long cast scorpions as bad-natured killers of hapless turtles that naively agree to ferry them across rivers. Michigan State University scientists, however, see them in a different light. (more…)

Asteroids Collide at 11,000 Miles Per Hour; Scientists Study Debris

By Guest PostApril 30, 2011Science596 scheila, asteroid, collision of asteroids, david jewitt, dust plumes, earth, empire state building, evolution of the solar system, history of astronomy, hubble data, Hubble Space Telescope, jupiter, mars, NASA, new york, scheila, swift ultraviolet optical telescope, uvot

Scientists have captured and studied the collision of two asteroids for only the second time in the history of astronomy. In the May 20 edition of the Astrophysical Journal Letters (currently online), UCLA’s David Jewitt and colleagues report on observations from NASA’s Hubble Space Telescope of a large asteroid that was hit by a much smaller one.

On Dec. 11, 2010, astronomers noticed that an asteroid known as (596) Scheila had unexpectedly brightened and was sporting short-lived dust plumes. Data from NASA’s Swift satellite and Hubble Space Telescope showed that these changes likely occurred after Scheila was struck by a much smaller asteroid, probably in late November or early December. The shape, evolution and content of the plumes enabled the scientists to reconstruct what occurred. (more…)

From the Beginning, the Mind Knows the Difference Between Night and Day

By Guest PostApril 28, 2011Scienceaugust kampf-lassin, basic human behaviors, biological rhythms, brain, brian prendergast, circadian rhythms, circadian system, hamster circadian visual system, primates, sunrise, sunset, university of chicago, visual stimuli

The brain is apparently programmed from birth to develop the ability to determine sunrise and sunset, new research on circadian rhythms at the University of Chicago shows.

The research sheds new light on brain plasticity and may explain some basic human behaviors, according to Brian Prendergast, associate professor in psychology, and co-author of a paper published April 27 in the journal PLoS One. The lead author is August Kampf-Lassin, an advanced graduate student at the University. (more…)

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