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First Stars, Galaxies Formed more Rapidly than Expected

By Guest PostSeptember 9, 2012Scienceanalysis, anisotropy probe, Antarctica, astronomer, background, Berkeley, california, christian reichardt, cmb, cosmic microwave, cosmological evolution, data, earth axis, electron, Epoch, Galaxy, geographic, herschel satellite, high resolution, hydrogen atom, image, john carlstrom, kavli foundation, microwave, millimeter wavelength, national, neutral, neutral gas, oliver zahn, period, plasma, polar plateau, proton, radiation, reionization, s chandrasekhar, science foundation, south pole, star, telescope, ultraviolet light, universe, university, wilkinson

Analysis of data from the National Science Foundation’s South Pole Telescope, for the first time, more precisely defines the period of cosmological evolution when the first stars and galaxies formed and gradually illuminated the universe. The data indicate that this period, called the epoch of reionization, was shorter than theorists speculated — and that it ended early.

“We find that the epoch of reionization lasted less than 500 million years and began when the universe was at least 250 million years old,” said Oliver Zahn, a postdoctoral fellow at the Berkeley Center for Cosmological Physics at the University of California, Berkeley, who led the study. “Before this measurement, scientists believed that reionization lasted 750 million years or longer, and had no evidence as to when reionization began.” (more…)

NSF’s South Pole Telescope Discovers a Galaxy Cluster Creating Stars at a Record Pace

By Guest PostAugust 16, 2012Scienceantarctic program, Antarctica, big bang, black hole, blanco 4 meter, bradford benson, chandra, Chile, cmb, cosmic microwave background, earth, energy, galaxy cluster, hubble fellow, john carlstrom, light year, magellan telescope, michael mcdonald, NASA, national science foundation, nsf, phoenix cluster, radiation, radio telescope, south pole telescope, spt, spt clj2344-4243, sunyaev zeldovich, sz effect, university of chicago, xray observatory

Researchers say Phoenix Cluster activity may cause scientists to rethink how galaxies evolve

A National Science Foundation-funded radio telescope in Antarctica has found an extraordinary galaxy cluster that may force astronomers to rethink how galaxy clusters and the galaxies that inhabit them evolve.

The galaxy cluster was discovered some 5.7 billion light years from Earth by the 10-meter wide South Pole Telescope (SPT) located at NSF’s Amundsen-Scott South Pole Station in Antarctica, which is funded by NSF’s Office of Polar Programs. (more…)

Today in the Milky Way: Cloudy Skies

By Guest PostJune 30, 2012Scienceadam block, aquila dark cloud, aquila rift arcs, astronomy picture, cloudy skies, dust lanes, Galaxy, gas and dust, herbig haro object, hh32, infrared, ldn 673, light years, Milky Way, mount lemmon skycenter, radiation, radio wave, rno 109, schulmann telescope, stellar winds, summer triangle, university of arizona

Adam Block of the UA’s Mount Lemmon SkyCenter brings us a rare view of the clouds wafting through our Milky Way in this Astronomy Picture of the Day.

In silhouette against the Milky Way’s faint starlight, its dusty molecular clouds likely contain raw material to form hundreds of thousands of stars, prompting astronomers to eagerly search the clouds for telltale signs of star birth.

This telescopic close-up looks toward the region at a fragmented Aquila dark cloud complex identified as LDN 673, stretching across a field of view slightly wider than the full moon.

For this image selected by NASA as the June 29 Astronomy Picture of the Day, astrophotographer Adam Block of the University of Arizona’s Mount Lemmon SkyCenter remotely operated the 32-inch Schulmann Telescope to peer into the vast chasms of gas and dust wafting through the Milky Way, exposing for about 15 minutes at a time during several nights in April and May. (more…)

U.S. Students Need New Way of Learning Science

By Guest PostApril 7, 2012Educationamerican students, atoms, cells, conservation of mass and energy, digital organisms, energy, forces, genomics, k 12 school, michigan state university, next generation, prom se, radiation, research project, Science, science standard, scientific fact, simon billinge, stephen pruitt, student assessment, synthetic biology, systems change, united states, variation, william schmidt

EAST LANSING, Mich. — American students need a dramatically new approach to improve how they learn science, says a noted group of scientists and educators led by Michigan State University professor William Schmidt.

After six years of work, the group has proposed a solution. The 8+1 Science concept calls for a radical overhaul in K-12 schools that moves away from memorizing scientific facts and focuses on helping students understand eight fundamental science concepts. The “plus one” is the importance of inquiry, the practice of asking why things happen around us – and a fundamental part of science. (more…)

Stars Pop Onto the Scene in New WISE Image

By Guest PostJanuary 13, 2012Scienceamerican astronomical society, astronomers, bubbles, cosmic clouds, dave leisawitz, gas and dust, milky way galaxy, mosaic, NASA, natal clouds, nebulae, new star birth, newborn stars, public astronomy, radiation, space telescope, specimens, star formation, star forming clouds, triggered star formation, triggered star formation theory, wide field infrared survey explorer, wise, wise mosaic, xavier koenig

PASADENA, Calif. — A new, large mosaic from NASA’s Wide-Field Infrared Survey Explorer (WISE) showcases a vast stretch of cosmic clouds bubbling with new star birth. The region — a 1,000-square-degree chunk of our Milky Way galaxy — is home to numerous star-forming clouds, where massive stars have blown out bubbles in the gas and dust.

“Massive stars sweep up and destroy their natal clouds, but they continuously spark new stars to form along the way,” said WISE Mission Scientist Dave Leisawitz of NASA Goddard Space Flight Center, Greenbelt, Md. Leisawitz is co-author of a new paper reporting the results in the Astrophysical Journal. “Occasionally a new, massive star forms, perpetuating the sequence of events and giving rise to the dazzling fireworks display seen in this WISE mosaic.” (more…)

Non-Ionizing Radiation From Cell Phones May Cause Cancer

By PravdaJune 1, 2011Health, Technologyamerican cancer experts, brij sood, cancerous tumors, carcinogens, cell phones, data on cell phone safety, france, frequency, harrisburg hospital, international agency for research on cancer, lyon, microwav, non ionizing, radiation, radiation oncologist, wireless headset, world health organization, x ray

A branch of the World Health Organization announced Tuesday cell phones are “possible carcinogens” — a statement that was met with skepticism from many American cancer experts.

The statement came from the International Agency for Research on Cancer, which convened 30 international experts in Lyon, France, this past week to sort through data on cell phone safety, reports Lancaster Eagle Gazette. (more…)

Radiation Hazard Issued for Japanese Spianch and Milk

By PravdaMarch 21, 2011Environment, Healthcaesium, canola, chrysanthemum greens, fukushima prefecture, health hazard, ibaraki prefecture, iodine, milk, nuclear power plant, radiation, radioactive substances, spinach, tokyo metropolitan area, ukushima, vegetables

The government is considering restricting shipments of spinach and milk from certain areas near the quake-damaged Fukushima No. 1 nuclear power plant because radiation stronger than permissible standards has been detected in those products.

Radioactive substances exceeding national standards have been detected in samples of spinach from Ibaraki Prefecture and of raw milk from Fukushima Prefecture, the government said late Saturday. (more…)

Nuclear Materials Detector Shows Exact Location of Radiation Sources

By Guest PostNovember 3, 2010Science18 cubes, cadmium zinc telluride, conventional detectors, gamma ray detector, gamma rays, high energy photons, nuclear engineering, nuclear materials, nuclear weapons, particles of light, polaris, radiation, radiation source, semiconductor, university of michigan, zhong he

The new Polaris gamma ray detector can pinpoint the location of special nuclear materials, such as those used for dirty bombs or nuclear weapons. Image credit: Zhong He

ANN ARBOR, Mich.— A table-top gamma-ray detector created at the University of Michigan can not only identify the presence of dangerous nuclear materials, but can pinpoint and show their exact location and type, unlike conventional detectors.

“Other gamma ray detectors can tell you perhaps that nuclear materials are near a building, but with our detector, you can know the materials are in room A, or room B, for example,” said Zhong He, an associate professor in the Department of Nuclear Engineering and Radiological Sciences.

“This is the first instrument for this purpose that can give you a real-time image of the radiation source. Not only can we tell you what material is there, but we can tell you where it is, and you can find it and walk towards it.” (more…)

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