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Title: Additional experimental evidence for a solar influence on nuclear decay rates
Authors: Jere H. Jenkins, Kevin R. Herminghuysen, Thomas E. Blue, Ephraim Fischbach, Daniel Javorsek II, Andrew C. Kauffman, Daniel W. Mundy, Peter A. Sturrock, Joseph W. Talnagi

Additional experimental evidence is presented in support of the recent hypothesis that a possible solar influence could explain fluctuations observed in the measured decay rates of some isotopes. These data were obtained during routine weekly calibrations of an instrument used for radiological safety at The Ohio State University Research Reactor using Cl-36. The detector system used was based on a Geiger-Mueller gas detector, which is a robust detector system with very low susceptibility to environmental changes. A clear annual variation is evident in the data, with a maximum relative count rate observed in January/February, and a minimum relative count rate observed in July/August, for seven successive years from July 2005 to June 2011. This annual variation is not likely to have arisen from changes in the detector surroundings, as we show here.

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New system could predict solar flares, give advance warning

Researchers may have discovered a new method to predict solar flares more than a day before they occur, providing advance warning to help protect satellites, power grids and astronauts from potentially dangerous radiation.
The system works by measuring differences in gamma radiation emitted when atoms in radioactive elements "decay," or lose energy. This rate of decay is widely believed to be constant, but recent findings challenge that long-accepted rule.

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Killer Solar Flares Are a Physical Impossibility

Given a legitimate need to protect Earth from the most intense forms of space weather - great bursts of electromagnetic energy and particles that can sometimes stream from the sun - some people worry that a gigantic "killer solar flare" could hurl enough energy to destroy Earth. Citing the accurate fact that solar activity is currently ramping up in its standard 11-year cycle, there are those who believe that 2012 could be coincident with such a flare.
But this same solar cycle has occurred over millennia. Anyone over the age of 11 has already lived through such a solar maximum with no harm. In addition, the next solar maximum is predicted to occur in late 2013 or early 2014, not 2012.
Most importantly, however, there simply isn't enough energy in the sun to send a killer fireball 93 million miles to destroy Earth.

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The Secret Lives of Solar Flares

 One hundred and fifty two years ago, a man in England named Richard Carrington discovered solar flares. 
It happened at 11:18 AM on the cloudless morning of Thursday, September 1st, 1859. Just as usual on every sunny day, the 33-year-old solar astronomer was busy in his private observatory, projecting an image of the sun onto a screen and sketching what he saw. On that particular morning, he traced the outlines of an enormous group of sunspots. Suddenly, before his eyes, two brilliant beads of white light appeared over the sunspots; they were so bright he could barely stand to look at the screen.

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Title: New Solar Extreme-ultraviolet Irradiance Observations during Flares
Authors: Thomas N. Woods, Rachel Hock, Frank Eparvier, Andrew R. Jones, Phillip C. Chamberlin, James A. Klimchuk, Leonid Didkovsky, Darrell Judge, John Mariska, Harry Warren, Carolus J. Schrijver, David F. Webb, Scott Bailey and W. Kent Tobiska

New solar extreme-ultraviolet (EUV) irradiance observations from the NASA Solar Dynamics Observatory (SDO) EUV Variability Experiment provide full coverage in the EUV range from 0.1 to 106 nm and continuously at a cadence of 10 s for spectra at 0.1 nm resolution and even faster, 0.25 s, for six EUV bands. These observations can be decomposed into four distinct characteristics during flares. First, the emissions that dominate during the flare's impulsive phase are the transition region emissions, such as the He II 30.4 nm. Second, the hot coronal emissions above 5 MK dominate during the gradual phase and are highly correlated with the GOES X-ray. A third flare characteristic in the EUV is coronal dimming, seen best in the cool corona, such as the Fe IX 17.1 nm. As the post-flare loops reconnect and cool, many of the EUV coronal emissions peak a few minutes after the GOES X-ray peak. One interesting variation of the post-eruptive loop reconnection is that warm coronal emissions (e.g., Fe XVI 33.5 nm) sometimes exhibit a second large peak separated from the primary flare event by many minutes to hours, with EUV emission originating not from the original flare site and its immediate vicinity, but rather from a volume of higher loops. We refer to this second peak as the EUV late phase. The characterisation of many flares during the SDO mission is provided, including quantification of the spectral irradiance from the EUV late phase that cannot be inferred from GOES X-ray diagnostics.

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Something New On the Sun: SDO Spots a Late Phase in Solar Flares

The sun's surface dances. Giant loops of magnetised solar material burst up, twist, and fall back down. Some erupt, shooting radiation flares and particles out into space. Forced to observe this dance from afar, scientists use all the tools at their disposal to look for patterns and connections to discover what causes these great explosions. Mapping these patterns could help scientists predict the onset of space weather that bursts toward Earth from the sun, interfering with communications and Global Positioning System (GPS) signals.
Analysis of 191 solar flares since May 2010 by NASA's Solar Dynamics Observatory (SDO) has recently shown a new piece in the pattern: some 15 percent of the flares have a distinct "late phase flare" some minutes to hours later that has never before been fully observed. This late phase of the flare pumps much more energy out into space than previously realised.

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NASA SDO SDO Spots Late Phase in Flares



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