Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Columbia crew catches a mysterious TIGER in the Indian Ocean

18.01.2005


An unprecedented flash observed by the space shuttle Columbia crew in 2003 over the Indian Ocean may be a new type of transient luminous event, like lightning sprites, but one that is not necessarily caused by a thunderstorm. The discharge was observed less than two weeks before the shuttle was lost during its Earth reentry.



The authors describe the discharge as a Transient Ionospheric Glow Emission in Red, or TIGER, event. It was recorded by a video camera in the near-infrared spectrum in the nighttime sky just south of Madagascar on 20 January 2003. The authors analyzed the video several months later and found what visually looks like a bright flash. They report that the emission did not resemble any known class of luminous events, which typically appear in conjunction with thunderstorm activity.

The space shuttle experiment that observed the unusual discharge was conducted by Israeli astronaut Ilan Ramon as part of the MEIDEX (Mediterranean Israeli Dust Experiment), and is reported by Yoav Yair of the Open University of Israel and an international group of colleagues. The article will be published on 18 January in Geophysical Research Letters, a journal of the American Geophysical Union.


The researchers also analyzed ground and satellite measurements of lightning in the region and note that the particular flash was not detected by equipment monitoring the skies for electromagnetic radiation in the very low and extremely low frequency domains usually associated with strong lightning discharges. In fact, no cloud-to-ground lightning was seen in the area for nearly two seconds around the emission’s detection time. They note, however, that meteor trails were observed by the same equipment on another orbit two days later and posit that an extraterrestrial source of the event cannot be discounted.

They note that the TIGER event was delayed from a distant lightning flash far longer than previously observed sprite or ELVES discharges and did not retain the jellyfish like (sprites) or doughnut (ELVES) shape often seen in those emissions. Most sprites, for example, appear within 10 milliseconds or less after strong positive cloud-to-ground flashes, while the observed event was delayed for nearly a quarter of a second and was approximately 1,000 kilometers [600 miles] removed from the closest visible lightning flash. For those reasons and the fact that 17 other luminous emissions detected at other times by the Columbia equipment were easily classified, the authors believe that the unusual event was likely a new type of emission, rather than a delayed sprite.

"The major point of this research, in my mind, is to show that there are some upper atmosphere processes that we do not know enough about," Yair said about the study. "The best way we can monitor or research this properly is from space."

The research team found no errors in its equipment and note that the sky was clear in the direct vicinity of their observations, leading them to discount suppositions that the emission may have been a reflection from another type of flash. They also suggest that meteors--still another possibility--would likely have produced a continuous trail of emissions that would have been seen during the short period when the astronauts observed and recorded the flash.

A third proposed explanation is that electron beams emitted from lightning in thunderstorms believed to be present near Cyprus at around the same time may have been carried by the Earth’s geomagnetic field into the upper atmosphere and created a purple glow near Madagascar, similar to a sprite that would have had nearly equal red and blue intensities. The authors discount that possibility, however, noting that the thunderstorm did not produce strong enough lightning to spark the TIGER event. The researchers indicate that further space-based observations may be able to detect similar instances of such emissions and help to solve the mystery of its cause.

Harvey Leifert | EurekAlert!
Further information:
http://www.agu.org

More articles from Earth Sciences:

nachricht NASA eyes Pineapple Express soaking California
24.02.2017 | NASA/Goddard Space Flight Center

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>