Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Giant blue jet caught on film

14.03.2002


Flashes this big might explain the 300,000-volt difference between the ionosphere and the ground


A sprite is like a blue jet but travels the other way.
© Uni. Alaska Fairbanks


Blue jets connect Earth’s electric circuit.

Video images captured in Puerto Rico suggest that blue flashes of light, much like lightning, feed energy from thunderstorms up into the Earth’s ionosphere - a blanket of electrically charged air some 70 kilometres above the ground1.

Some researchers suspect that such phenomena may also fix nitrogen for plants to use and interact with the ozone layer2.



The images, taken in September 2001, show the largest blue jet ever to be caught on camera. "It really was a gigantic flash," says Victor Pasko of Pennsylvania State University, who led the observation team. "With the naked eye you could even see it rising," he recalls.

Blue jets are often associated with thunderstorms, but until now were thought to be relatively small. The Puerto Rican jet stretched from the top of a small thunderstorm to the lower edge of the ionosphere, filling an estimated 6,000 cubic kilometres of atmosphere.

Flashes this big might explain the 300,000-volt difference between the charge of the ionosphere and the ground. Physicists have long agreed that something must link the two regions to complete the global electrical circuit (GEC). Until the latest film, nothing had been seen that reached high enough from the cloud tops to do the job.

"We knew the currents were there, but there was no visual evidence" says Davis Sentman, the physicist at the University of Alaska in Fairbanks who discovered blue jets in 1994. The film "really advances the science in this field", he says.

That the sighting was associated with the kind of small, localized storm common worldwide, suggests that large blue jets could also be common. If so, they might influence atmospheric chemistry: their electrical energy could encourage gases to react with one another. "The effect may be there but we don’t know if it’s dramatically important," admits Pasko.

Sprites, elves, trolls and pixies

In the past decade, high-speed, light-sensitive cameras have allowed scientists to describe a menagerie of electrical phenomena, which bear names that would be more at home in a Tolkien novel than a physics textbook. Sprites, blue jets and associated flashes called elves, crawlers, trolls and pixies are all fleeting electrical discharges that accompany thunderstorms.

All these phenomena are hard to spot, as they last for less than a blink of an eye and are obscured from below by cloud. They can be glimpsed along storm fronts and from aeroplanes flying above the clouds.

Sprites, which might also help to maintain the GEC, work a bit like blue jets in reverse. They are pink, or sometimes red, and occur when current from just below the ionosphere moves downwards towards thunderstorms. As with jets, this current excites atoms along the way, causing them to emit light.

References

  1. Pasko, V. P., Stanley, M. A., Mathews, J. D., Inan, U. S. & Wood, T. G. Electrical discharge from a thundercloud top to the lower ionosphere. Nature, 416, 152 - 154, (2002).
  2. Mishin, E. Ozone layer perturbation by a single blue jet. Geophysical Research Letters, 24, 1919 - 1922, (1997).


TOM CLARKE | © Nature News Service

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>