Astronomy Report Astronomy Report
Recent News |  Archives |  Tags |  Space Weather |  Space Weather Email Alerts (New!) |  About |  Newsletter |  Submit News |  Links |  Subscribe to AstronomyReport.com RSS Feed Subscribe


More Articles
New blood: Tracing the beginnings of hematopoietic stem cellsNew blood: Tracing the beginnings of hematopoietic stem cells

New study takes the shine off magpie folkloreNew study takes the shine off magpie folklore

A shift in the code: New method reveals hidden genetic landscapeA shift in the code: New method reveals hidden genetic landscape

Highs and lows: Height changes in the ice sheets mappedHighs and lows: Height changes in the ice sheets mapped

Despite academic achievement, pay gaps likely continue between the racesDespite academic achievement, pay gaps likely continue between the races

Bats bolster brain hypothesis, maybe technology, tooBats bolster brain hypothesis, maybe technology, too

New discovery: Microbes create dripstonesNew discovery: Microbes create dripstones

Common household chemicals decrease reproduction in mice, study findsCommon household chemicals decrease reproduction in mice, study finds

Program earns kudos for improving grades, retaining studentsProgram earns kudos for improving grades, retaining students

Scientists enhance synthesis of chromium dioxide (100) epitaxial thin film growthScientists enhance synthesis of chromium dioxide (100) epitaxial thin film growth

Has the puzzle of rapid climate change in the last ice age been solved?Has the puzzle of rapid climate change in the last ice age been solved?

Lithium-based neutron detector named among Top 100 technologies of the yearLithium-based neutron detector named among Top 100 technologies of the year

A self-organizing thousand-robot swarmA self-organizing thousand-robot swarm

Genetically engineered fruit flies could save cropsGenetically engineered fruit flies could save crops

Eco-friendly 'pre-fab nanoparticles' could revolutionize nano manufacturingEco-friendly 'pre-fab nanoparticles' could revolutionize nano manufacturing

Diamonds are a quantum computer's best friendDiamonds are a quantum computer's best friend

Our ancestor's 'leaky' membrane answers big questions in biologyOur ancestor's 'leaky' membrane answers big questions in biology

Crash-testing rivetsCrash-testing rivets

Scientists discover the miracle of how geckos move, cling to ceilingsScientists discover the miracle of how geckos move, cling to ceilings

Photo editing algorithm changes weather, seasons automaticallyPhoto editing algorithm changes weather, seasons automatically

Geography matters: Model predicts how local 'shocks' influence U.S. economyGeography matters: Model predicts how local 'shocks' influence U.S. economy

Shrinking dinosaurs evolved into flying birdsShrinking dinosaurs evolved into flying birds

Running for life: How speed restricts evolutionary change of the vertebral columnRunning for life: How speed restricts evolutionary change of the vertebral column

Protein's 'hands' enable bacteria to establish infection, research findsProtein's 'hands' enable bacteria to establish infection, research finds

A healthy lifestyle adds years to lifeA healthy lifestyle adds years to life

Do probiotics help kids with stomach bugs?Do probiotics help kids with stomach bugs?

Strict diet suspends development, doubles lifespan of wormsStrict diet suspends development, doubles lifespan of worms

Identified for the first time what kind of explosive has been used after the detonationIdentified for the first time what kind of explosive has been used after the detonation

Copied from nature: Detecting software errors via genetic algorithmsCopied from nature: Detecting software errors via genetic algorithms

The strange case of solar flares and radioactive elements (8/25/2010)

Tags:
solar flares, space weather
NASA SDO AIA 304 - Solar Flare
NASA SDO AIA 304 - Solar Flare

It's a mystery that presented itself unexpectedly: The radioactive decay of some elements sitting quietly in laboratories on Earth seemed to be influenced by activities inside the sun, 93 million miles away.

Is this possible?

Researchers from Stanford and Purdue University believe it is. But their explanation of how it happens opens the door to yet another mystery.

There is even an outside chance that this unexpected effect is brought about by a previously unknown particle emitted by the sun. "That would be truly remarkable," said Peter Sturrock, Stanford professor emeritus of applied physics and an expert on the inner workings of the sun.

The story begins, in a sense, in classrooms around the world, where students are taught that the rate of decay of a specific radioactive material is a constant. This concept is relied upon, for example, when anthropologists use carbon-14 to date ancient artifacts and when doctors determine the proper dose of radioactivity to treat a cancer patient.

Random numbers

But that assumption was challenged in an unexpected way by a group of researchers from Purdue University who at the time were more interested in random numbers than nuclear decay. (Scientists use long strings of random numbers for a variety of calculations, but they are difficult to produce, since the process used to produce the numbers has an influence on the outcome.)

Ephraim Fischbach, a physics professor at Purdue, was looking into the rate of radioactive decay of several isotopes as a possible source of random numbers generated without any human input. (A lump of radioactive cesium-137, for example, may decay at a steady rate overall, but individual atoms within the lump will decay in an unpredictable, random pattern. Thus the timing of the random ticks of a Geiger counter placed near the cesium might be used to generate random numbers.)

As the researchers pored through published data on specific isotopes, they found disagreement in the measured decay rates - odd for supposed physical constants.

Checking data collected at Brookhaven National Laboratory on Long Island and the Federal Physical and Technical Institute in Germany, they came across something even more surprising: long-term observation of the decay rate of silicon-32 and radium-226 seemed to show a small seasonal variation. The decay rate was ever so slightly faster in winter than in summer.

Was this fluctuation real, or was it merely a glitch in the equipment used to measure the decay, induced by the change of seasons, with the accompanying changes in temperature and humidity?

"Everyone thought it must be due to experimental mistakes, because we're all brought up to believe that decay rates are constant," Sturrock said.

The sun speaks

On Dec 13, 2006, the sun itself provided a crucial clue, when a solar flare sent a stream of particles and radiation toward Earth. Purdue nuclear engineer Jere Jenkins, while measuring the decay rate of manganese-54, a short-lived isotope used in medical diagnostics, noticed that the rate dropped slightly during the flare, a decrease that started about a day and a half before the flare.

If this apparent relationship between flares and decay rates proves true, it could lead to a method of predicting solar flares prior to their occurrence, which could help prevent damage to satellites and electric grids, as well as save the lives of astronauts in space.

The decay-rate aberrations that Jenkins noticed occurred during the middle of the night in Indiana - meaning that something produced by the sun had traveled all the way through the Earth to reach Jenkins' detectors. What could the flare send forth that could have such an effect?

Jenkins and Fischbach guessed that the culprits in this bit of decay-rate mischief were probably solar neutrinos, the almost weightless particles famous for flying at almost the speed of light through the physical world - humans, rocks, oceans or planets - with virtually no interaction with anything.

Then, in a series of papers published in Astroparticle Physics, Nuclear Instruments and Methods in Physics Research and Space Science Reviews, Jenkins, Fischbach and their colleagues showed that the observed variations in decay rates were highly unlikely to have come from environmental influences on the detection systems.

Reason for suspicion

Their findings strengthened the argument that the strange swings in decay rates were caused by neutrinos from the sun. The swings seemed to be in synch with the Earth's elliptical orbit, with the decay rates oscillating as the Earth came closer to the sun (where it would be exposed to more neutrinos) and then moving away.

So there was good reason to suspect the sun, but could it be proved?

Enter Peter Sturrock, Stanford professor emeritus of applied physics and an expert on the inner workings of the sun. While on a visit to the National Solar Observatory in Arizona, Sturrock was handed copies of the scientific journal articles written by the Purdue researchers.

Sturrock knew from long experience that the intensity of the barrage of neutrinos the sun continuously sends racing toward Earth varies on a regular basis as the sun itself revolves and shows a different face, like a slower version of the revolving light on a police car. His advice to Purdue: Look for evidence that the changes in radioactive decay on Earth vary with the rotation of the sun. "That's what I suggested. And that's what we have done."

A surprise

Going back to take another look at the decay data from the Brookhaven lab, the researchers found a recurring pattern of 33 days. It was a bit of a surprise, given that most solar observations show a pattern of about 28 days - the rotation rate of the surface of the sun.

The explanation? The core of the sun - where nuclear reactions produce neutrinos - apparently spins more slowly than the surface we see. "It may seem counter-intuitive, but it looks as if the core rotates more slowly than the rest of the sun," Sturrock said.

All of the evidence points toward a conclusion that the sun is "communicating" with radioactive isotopes on Earth, said Fischbach.

But there's one rather large question left unanswered. No one knows how neutrinos could interact with radioactive materials to change their rate of decay.

"It doesn't make sense according to conventional ideas," Fischbach said. Jenkins whimsically added, "What we're suggesting is that something that doesn't really interact with anything is changing something that can't be changed."

"It's an effect that no one yet understands," agreed Sturrock. "Theorists are starting to say, 'What's going on?' But that's what the evidence points to. It's a challenge for the physicists and a challenge for the solar people too."

If the mystery particle is not a neutrino, "It would have to be something we don't know about, an unknown particle that is also emitted by the sun and has this effect, and that would be even more remarkable," Sturrock said.

Note: This story has been adapted from a news release issued by the Stanford University

Comments:

1. Branden

8/25/2010 10:24:44 AM MST

Does this mean that radiocarbon dating is inaccurate? What radioactive isotopes is it affecting specifically?


2. I12CUDI

8/25/2010 11:07:00 AM MST

Branden,

This article only applies to manganese-54, even though the author used Carbon-14 as an example of radioactive decay. However, I'm sure this paper will cause nuclear physicists around the globe to take a look at other radioactive isotopes.


Leave a Reply:

Solar X-rays

Geomagnetic Field

Search
New Articles
Mysteries of space dust revealedMysteries of space dust revealed

New Milky Way maps help solve stubborn interstellar material mystery

Research uncovers forces that hold gravity-defying near-earth asteroid togetherResearch uncovers forces that hold gravity-defying near-earth asteroid together

Monitoring meteor showers from spaceMonitoring meteor showers from space

Scientists discover interstellar stardustScientists discover interstellar stardust

Supperrotation on Venus and Titan, exploratory modeling

All-you-can-eat at the end of the universeAll-you-can-eat at the end of the universe

Astrophysicists detect destruction of 3 stars by black holes

Follow the radio waves to exomoons, physicists sayFollow the radio waves to exomoons, physicists say

Taking astronomy to the next levelTaking astronomy to the next level

White dwarfs crashing into neutron stars explain loneliest supernovaeWhite dwarfs crashing into neutron stars explain loneliest supernovae

Violent solar system history uncovered by WA meteorite

Step closer to birth of the sun

NASA's Hubble finds supernova star system linked to potential 'zombie star'NASA's Hubble finds supernova star system linked to potential 'zombie star'

Triangulum galaxy snapped by VSTTriangulum galaxy snapped by VST



Archives
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007


Science Friends
Agricultural Science
Sports Tech
Biology News
Biomimicry Science
Cognitive Research
Chemistry News
Tissue Engineering
Cancer Research
Cybernetics Research
Electonics Research
Forensics Report
Fossil News
Genetic Archaeology
Genetics News
Geology News
Microbiology Research
Nanotech News
Parenting News
Physics News


  Archives |  Submit News |  Advertise With Us |  Contact Us |  Links
Use of this site constitutes acceptance of our Terms of Service and Privacy Policy. All contents © 2000 - 2015 Web Doodle, LLC. All rights reserved.