Archive

Posts Tagged ‘light’

Scientists Detect ‘Dark Lightning’ Energy Burst Linked to Visible Lightning

April 25, 2013 1 comment

Apr. 24, 2013 — Researchers have identified a burst of high-energy radiation known as ‘dark lightning” immediately preceding a flash of ordinary lightning. The new finding provides observational evidence that the two phenomena are connected, although the exact nature of the relationship between ordinary bright lightning and the dark variety is still unclear, the scientists said.

Three images, left to right, of the same thundercloud depict a less-than-10-milliseconds-long sequence of events: (left) formation within the cloud of a small channel, or ‘leader,’ of electrical conductivity (yellow line) with weak emission of radio signals (ripples), to (middle) a burst of both dark lightning (pink) and radio waves (larger ripples), to (right) a discharge of bright lightning and more radio waves. (Credit: Studio Gohde)

“Our results indicate that both these phenomena, dark and bright lightning, are intrinsic processes in the discharge of lightning,” said Nikolai Østgaard, who is a space scientist at the University of Bergen in Norway and led the research team.

He and his collaborators describe their findings in an article recently accepted in Geophysical Research Letters — a journal of the American Geophysical Union.

Dark lightning is a burst of gamma rays produced during thunderstorms by extremely fast moving electrons colliding with air molecules. Researchers refer to such a burst as a terrestrial gamma ray flash.

Read more:http://www.sciencedaily.com/releases/2013/04/130424210319.htm

Advertisements

Army Demonstrates a Weapon That Shoots Laser-Guided Lightning Bolts


By Clay Dillow Posted 06.28.2012

Over at Picatinny Arsenal, the research and development facility and proving ground for the U.S. Army’s weaponry, engineers are developing a device that shoots lighting bolts along a laser beam to annihilate its target. That’s right: lighting bolts shot down laser beams. This story could easily end right here and still be the coolest thing we’ve written today, but for the scientifically curious we’ll continue.

Quantum Researchers Able to Stop and Restart Light


Wednesday, 27 June 2012

‘In two independent experiments that defy the notions of Einstein, researchers have been able to stop, then restart a beam of light.

Ordinarily, light travels at the speed of 186,282 miles per second, but the research team of Lene Hau, a professor of physics at Harvard, who in 1999 was able to slow light down to 38 miles per hour, has been able to trap light in a cloud of sodium atoms super-cooled to near ‘absolute zero.’’

Read more: Quantum Researchers Able to Stop and Restart Light

Gravitational Lensing: Astronomers Spot Rare Arc from Hefty Galaxy Cluster


ScienceDaily (June 26, 2012) — Seeing is believing, except when you don’t believe what you see. Astronomers using NASA’s Hubble Space Telescope have found a puzzling arc of light behind an extremely massive cluster of galaxies residing 10 billion light-years away. The galactic grouping, discovered by NASA’s Spitzer Space Telescope, was observed as it existed when the universe was roughly a quarter of its current age of 13.7 billion years. The giant arc is the stretched shape of a more distant galaxy whose light is distorted by the monster cluster’s powerful gravity, an effect called gravitational lensing. The trouble is, the arc shouldn’t exist.

These images, taken by NASA’s Hubble Space Telescope, show an arc of blue light behind an extremely massive cluster of galaxies residing 10 billion light-years away. (Credit: NASA/ESA/University of Florida, Gainsville/University of Missouri-Kansas City/UC Davis)
 

“When I first saw it, I kept staring at it, thinking it would go away,” said study leader Anthony Gonzalez of the University of Florida in Gainesville, whose team includes researchers from NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “According to a statistical analysis, arcs should be extremely rare at that distance. At that early epoch, the expectation is that there are not enough galaxies behind the cluster bright enough to be seen, even if they were ‘lensed,’ or distorted by the cluster. The other problem is that galaxy clusters become less massive the further back in time you go. So it’s more difficult to find a cluster with enough mass to be a good lens for gravitationally bending the light from a distant galaxy.”

Read more: http://www.sciencedaily.com/releases/2012/06/120626131234.htm

By Twisting Light Signals into a Vortex, Researchers Create Fastest Wireless Connection Ever


By Clay Dillow 06.25.2012

By twisting radio waves into a threaded vortex, an international team of researchers has beamed data through the air at 2.5 terabits per second, creating what has to be the fastest wireless network ever created. Moreover, the technique used to create this effect has no real theoretical ceiling, ExtremeTech reports.

Nanotechnology Used to Harness Power of Fireflies


ScienceDaily (June 15, 2012) — What do fireflies, nanorods, and Christmas lights have in common? Someday, consumers may be able to purchase multicolor strings of light that don’t need electricity or batteries to glow. Scientists at Syracuse University found a new way to harness the natural light produced by fireflies (called bioluminescence) using nanoscience. Their breakthrough produces a system that is 20 to 30 times more efficient than those produced during previous experiments.

Nanorods created with firefly enzymes glow orange. The custom, quantum nanorods are created in the laboratory of Mathew Maye, assistant professor of chemistry. (Credit: Image courtesy of Syracuse University)
 

It’s all about the size and structure of the custom, quantum nanorods, which are produced in the laboratory by Mathew Maye, assistant professor of chemistry in SU’s College of Arts and Sciences; and Rebeka Alam, a chemistry Ph.D. candidate. Maye is also a member of the Syracuse Biomaterials Institute. “Firefly light is one of nature’s best examples of bioluminescence,” Maye says. “The light is extremely bright and efficient. We’ve found a new way to harness biology for non-biological applications by manipulating the interface between the biological and non-biological components.”

Their work, “Designing Quantum Rods for Optimized Energy Transfer with Firefly Luciferase Enzymes,” was published online May 23 in Nano Letters and is forthcoming in print. Collaborating on the research were Professor Bruce Branchini and Danielle Fontaine, both from Connecticut College.

Read more: http://www.sciencedaily.com/releases/2012/06/120615114104.htm