Thermonuclear lightning - Astronomy News

Blobrana

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Date: Feb 17 01:05 2009

Ball lightning	Permalink

Two hundred years ago today a tremendous thunderstorm led to a bizarre incident. HMS Warren Hastings, one of the largest ships of its time, was moored off Portsmouth. Conditions were clear and calm in the morning but at about 3pm a storm swept in from the west. The wind blew, rain fell in torrents and thunder erupted. "In the midst of the confusion, occasioned by the storm, three distinct balls of fire were emitted from the heavens. One of them fell into the main topmast cross-trees, killed a man on the spot and set the main mast on fire." Read more __________________

Blobrana

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Date: Jul 15 19:29 2008

RE: Thermonuclear lightning	Permalink

University of Florida and Florida Institute of Technology engineering researchers have narrowed the search for the source of X-rays emitted by lightning, a feat that could one day help predict where lightning will strike. Read more __________________

Blobrana

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Date: Feb 21 17:43 2008

Ball lightning	Permalink

Scientists have been baffled for centuries about the strange drifting balls of light that appear occasionally during thunderstorms. Theories put forward so far suggest that this ball lightning is either a moving electrical discharge or that it is some kind of self-contained object. Now, research from an Israeli group is making the latter seem more likely. The scientists have created artificial fireballs and then used the European Synchrotron Radiation Facility (ESRF) in Grenoble to analyse their composition. They discovered that the fireballs contain about 10^9 particles per cm^3, each of which has an average diameter of about 50 nm Read more __________________

Blobrana

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Posts: 131433

Date: Dec 24 14:53 2007

Thermonuclear lightning	Permalink

Koreas first astronaut will collect detailed photographic data on mega-lightning that occurs in the earths stratosphere, the government said Monday (Dec. 24). The Ministry of Science and Technology and the Korea Aerospace Research Institute (KARI) said astronaut Ko San will use a locally developed micro-electro mechanical systems (MEMS) telescope to capture the unexplained atmospheric phenomenon for future research. He is scheduled to blast off into space on April 8 from the Baikonur Cosmodrome in Kazakhstan and stay in orbit for eight days. Read more __________________

Blobrana

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Date: Jun 16 10:33 2007

Dangers of lightning	Permalink

More than 80 per cent of deaths that occur due to lightning can be avoided if the public is made aware about dangers of lightning, astronomer Dr. Chandana Jayaratne said. Read More __________________

Blobrana

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Date: Jan 11 00:51 2007

Lightning balls created in the lab	Permalink

Ball lightning could soon lose its status as a mystery, now that a team in Brazil has cooked up a simple recipe for making similar eerie orbs of light in the lab, even getting them to bounce around for several seconds. Thousands of people have reported seeing ball lightning, a luminous sphere that sometimes appears during thunderstorms. It is typically the size of a grapefruit and lasts for a few seconds or minutes, sometimes hovering, even bouncing along the ground. Read more __________________

Blobrana

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Date: Sep 14 23:52 2006

Electric Ice	Permalink

Miles above Earth in cumulonimbus clouds, tiny ice crystals are constantly bumping against larger ice pellets. The two kinds of ice rubbing together act like socks rubbing against carpet. Zap! Before you know it, the cloud is crackling with electric potential—and a bolt of lightning explodes to the ground. It may seem hard to believe that a powerful bolt of lightning, which heats the air in its path three times hotter than the surface of the sun, could spring from little pieces of ice. But that's how it is, according to theory, and indeed laboratory experiments have confirmed that you can generate electricity from ice-ice collisions. Read more __________________

Blobrana

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Date: Feb 10 22:38 2006

Ball lightning	Permalink

Researchers in Israel have built a system that can create lightning balls in the lab. The work may not only help us to understand ball lightning but could even lead to practical applications that make use of the strange phenomena. Ball lightning is thought to be a ball of plasma that is formed when a bolt of lightning hits the ground and creates a molten "hot spot". The ball can typically measure 30 centimetres across and can last for a few seconds. Although they are generally created during thunderstorms, Eli Jerby and Vladimir Dikhtyar from Tel Aviv University in Israel have now been able to make lightning balls in the lab using a "microwave drill". The device consists of the magnetron from a 600-watt domestic microwave oven and concentrates its power into a volume of just one cubic centimetre. The researchers inject the microwaves though a pointed rod into a solid substrate made from glass, silicon, germanium, aluminium or other ceramics. The energy from the microwaves then produces a molten hot spot in the substrate. What the scientists then do is pull the microwave drill out of the solid, which drags the molten hot spot and creates a hot drop. The drop then becomes a floating fireball that measures about 3 centimetres across and lasts for some tens of milliseconds. "The fireball looks like a hot jellyfish, quivering and buoyant in the air" - Eli Jerby . Although the composition of the laboratory fireballs still need to be verified, they seem to contain components of the substrate material in various phases, such as ions, neutral atoms and larger macroscopic particles. This is similar to natural lightning balls, which are thought to contain vapourised mineral grains from the soil that have been kicked into the atmosphere by a lightning strike. Moreover, the lab-produced fireballs appear to combine plasma and chemical oxidation and burning processes. Again, this is similar to naturally produced balls in which the vaporised sand grains are thought to react with oxygen in the air and burn to release light. "Our ability to generate such fireballs in a simple systematic manner may lead to techniques for synthesizing fireballs from solid materials" - Eli Jerby . He even hopes that the lab-generated fireballs could be used in practical applications such as coating, deposition, combustion and energy production. http://www.eng.tau.ac.il/~jerby/Fireballs.html __________________

Blobrana

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Posts: 131433

Date: Sep 15 20:20 2005

Thermonuclear lightning	Permalink

According to new research lightning produces a thermonuclear reaction, which generates a large amount of neutrons. To produce a thermonuclear reaction, it is necessary, to have nuclei with a large quantity of neutrons available, for example, deuterium nuclei, and these nuclei should possess sufficiently high velocity and merge together upon collision, having overcome the Coulomb barrier. It turns out that all these conditions are observed in the course of a lightning strike - such a conclusion is evident from calculations by B.M. Kuzhevsky, Ph.D. (Physics&Mathematics), head of the neutron research laboratory, Skobeltsin Scientific Research Institute of Nuclear Physics (Moscow State University). Deuterium is always present in water: on average, a molecule of DHO (water, where one of hydrogen atoms is replaced by deuterium) falls to 6,800 molecules of H2O. That means - taking into account the quantity of water vapour available in the atmosphere (i.e. 5х10^-4 g/cubic centimetre) - there will be 10^15 deuterium atoms per cubic centimetre. In lightning, these atoms turn into ions and are capable of gathering speed up to a considerable energy. With the lightning canal diameter varying from 2 millimetres to 5 centimetres, and discharge duration making the ten-thousandth of a second, it proves that billions of deuterium atoms will have time to start reacting with each other and to generate precisely two times less atoms of helium-3 and neutrons. These neutrons already possess enormous energy - 2.45 MeV. However, in the atmosphere they are capable of living at most for 0.2 seconds, during which they will inevitably meet with nitrogen atoms and be absorbed by them. This time period is sufficient for neutrons to fly a distance of one or two kilometres. The calculation has been also confirmed by experimental data. The DYAIZA facility developed at the Institute and installed in Moscow at the Vorobyevy Hills repeatedly recorded neutron emission peaks during thunderstorms, their magnitude exceeding that of the background by hundreds of times. Several important conclusions can be drawn from the above effort. Firstly, this helps to solve a long-standing puzzle: why cosmonauts on board the MIR space station observed high neutron background in the area of the equator. Keeping in mind that thunderstorms permanently burst out in this region, it is easy to guess where high neutron background comes from. Secondly, the same mechanism should also work in the atmospheres of Venus and Jupiter where thunderstorms are also frequent and sporadic neutron streams should arise there. That means that investigation of these planets' neutron emission should take into account this particular fact not to confuse by accident "thundery" neutrons with some other neutrons. source __________________

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