Subscribe free to our newsletters via your
. Nuclear Energy News .




BLUE SKY
Heliophysics Nugget: Seeing Sprites
by Karen C. Fox for Goddard Space Flight Center
Greenbelt MD (SPX) Aug 15, 2012


A sprite glows red in this image captured by astronauts on the International Space Station on April 30, 2012. Credit: Image Science and Analysis Laboratory, NASA Johnson Space Center. For a larger version of this image please go here.

High above the clouds during thunderstorms, some 50 miles above Earth a different kind of lightning dances. Bursts of red and blue light, known as "sprites," flash for a scant one thousandth of a second. They are often only visible to those in flight above a storm, and happen so quickly you might not even see it unless you chance to be looking directly at it.

One hard-to-reach place that gets a good view of sprites is the International Space Station. On April 30, 2012, astronauts on the ISS captured the signature red flash of a sprite, offering the world and researchers a rare opportunity to observe one.

Indeed, sprites are so hard to catch on film, that pilots had claimed to see them for almost a century before scientists at the University of Minnesota accidentally caught one on camera in July of 1989.

Since then, researchers aboard planes have occasionally snapped a shot, but it continues to be difficult to methodically film them. So a group of scientists, along with help from Japan's NHK television, sought them out regularly for two weeks in the summer of 2011.

Filming at 10,000 frames per second on two separate jets, the team recorded some of the best movies of sprites ever taken - movies that can be used to study this poorly understood phenomenon and the forces that create them. By filming from two jets flying 12 miles apart, the team mapped out the 3-dimensional nature of the sprites. Ground-based measurements rounded out the picture.

"Seeing these are spectacular," says Hans C. Stenbaek-Nielsen, a geophysicist at the University of Alaska in Fairbanks, Alaska.

"But we need the movies, because not only are they so fast that you could blink and miss them, but they emit most of their light in red, where the human eye is relatively blind."

During those two weeks, the scientists hopped into their planes in Denver, Colo. each evening and chased storm clouds. Just figuring out which direction to fly next was a full time job, assigned to a single person with a computer watching the weather systems. Once a plane found a hot zone of sprites, however, they often lucked into filming numerous sprites in a row.

The sprite's first flash is usually followed by a break up into numerous streamers of light - figuring out what causes this divergence is one of the key things researchers will try to understand from these films.

The basic understanding of sprites is that they are related to lightning, in which a neutrally charged cloud discharges some of the electricity to ground.

Normally negative charge is carried from the cloud to the ground, but about one out of every ten times it's positive charge - and that leaves the top of the cloud negatively charged. With this one in ten chance, the electric field above the cloud is "just right" to produce the sprite, an electrical discharge 50 miles above the thunderstorm.

Typically the weather we experience on the ground is considered to be a separate phenomenon from the weather that goes on higher up in the atmosphere, in the area known as the mesosphere. The sprites show, however, that some fundamental science connects these two regions, opening interesting physics questions about the interchange of energy between them.

.


Related Links
Goddard Space Flight Center
The Air We Breathe at TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








BLUE SKY
Meteor Smoke Makes Strange Clouds
Washington DC (SPX) Aug 15, 2012
Anyone who's ever seen a noctilucent cloud or "NLC" would agree: They look alien. The electric-blue ripples and pale tendrils of NLCs reaching across the night sky resemble something from another world. Researchers say that's not far off. A key ingredient for the mysterious clouds comes from outer space. "We've detected bits of 'meteor smoke' imbedded in noctilucent clouds," reports ... read more


BLUE SKY
Major advance made in generating electricity from wastewater

New process doubles production of alternative fuel while slashing costs

Senegalese villagers vow to fight biofuels project

AREVA invests in bio-coal

BLUE SKY
University of Houston researcher develops solar panel coating

Here Comes the Sun: NASA Picks Solar Array System Development Proposals

Lockheed Martin to Integrate Fuel Cells, Solar Power for Military Apps

Hanwha Solar Launches Project Development Business in North America

BLUE SKY
Wind farms: A danger to ultra-light aircraft?

Off-shore wind power project considered

Obama whips up wind power attack on Romney

Clegg: Gov't 'committed' to renewables

BLUE SKY
Drought hits U.S. power supply

Rwanda to begin geothermal drilling

Improved methods for predicting energy consumption

Paraguay row threatens Itaipu power deal

BLUE SKY
Ban calls for South China Sea dialogue

Japan arrests five men on disputed island: police

Venezuelan petrol to China up 60% since February: officials

KIT Controls Fluctuation of Renewable Energies by Using Modern Storage Systems

BLUE SKY
Five Potential Habitable Exoplanets Now

RIT Leads Development of Next-generation Infrared Detectors

UCF Discovers Exoplanet Neighbor

Can Astronomers Detect Exoplanet Oceans

BLUE SKY
Myanmar names navy chief as new vice president

India's nuclear submarine nears sea trials

Navantia use Paramarine Advance Marine Design Software in the development of naval ships and submarines

India's first nuclear submarine set for trials

BLUE SKY
India to launch Mars mission: PM

Mars rover captures crash landing

Obama to NASA experts: 'Let me know if you find Martians'

Opportunity Will Resume Driving Soon




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement