By Julie Imada
Academy Directorate of Research
Air Force Academy researchers were in Japan for the Wednesday solar eclipse, to help U.S. spacecraft better predict solar activity.
Academy physics professors Maj. Robert Lee and Lt. Col. D. Brent Morris are at Kadena Air Base, Japan for this summer’s solar eclipse, working to solve the a mystery about the sun’s possible influence on radioactive decay.
Major Lee and Colonel Morris are investigators on a joint Purdue University – Air Force Academy project examining a series of anomalies found in prior studies of half-lives in radioactive decay. Purdue University’s Professor Ephraim Fischbach and Mr. Jere Jenkins are co-principal investigators on the project. The group previously collaborated on a similar ground-breaking experiment at Thule Air Base, Greenland in 2008. The experiments near Kadena, on the island of Amami-Oshima, are meant to gather additional data to support the researchers’ speculations on the source of the anomalies.
For centuries, radioactive decay rates were thought to be constant, unvarying values. For example, Carbon-14, which is used to carbon date archaeological specimens, has a published half-life of about 5,600 years. However, Fischbach and Jenkins noticed that when the Earth is nearer the sun, some particular half-lives decline slightly, and when the earth moves further from the sun in its orbit, those particular half-lives grow slightly longer. Therefore, if the mechanism affecting the half-lives being investigated would hold true for Carbon-14, then based on what time of the year a specimen is analyzed, the dating results could potentially be off from what would be expected with a constant half-life.
Lee said earlier research at Purdue revealed a correlation between several sets of nuclear decay data and the distance between the earth and the sun in a manner that is independent of seasonal variables like temperature, pressure, and humidity. If this correlation holds true, the discovery would be extraordinary because generations of physicists have believed that half-lives are constant, he added. If researchers were to succeed in establishing the relationship between anomalies in the decays of the isotopes under study to solar activity, it may be possible to develop technology to anticipate some types of severe solar storm activity.
Such technology would be of tremendous interest not only to the Air Force, but also to the world-wide telecommunications industry, the space industry, and electric energy providers. Solar storms disrupt Department of Defense satellites, including the Global Positioning System, at an estimated cost of $300 million a year. Power grids can also become overloaded by solar storms and have caused billions of dollars in damage to grid infrastructures and resulted in large-scale electrical blackouts.
Unfortunately, solar storms are difficult to predict.
“The DoD relies very heavily on satellite-based communications. If we were able to predict solar activity, we could potentially plan our missions with that activity in mind and avoid operational and communications blackouts,” Lee said. “With a proven predictive model, commercial satellites and electrical networks could be shut down before damaging solar storms, saving billions of dollars for telecommunications and electricity providers around the world.”
These series of experiments are unique because of the nature of a solar eclipse. During the observation of a solar eclipse, the moon blocks almost all of the particles from the sun, with the notable exception of neutrinos – a near-massless sub-atomic particle that only rarely interacts with matter. The team suspects neutrinos may be the cause of the anomalies resulting in the observed non-constant radioactive decay. “Essentially, during an eclipse you get to ‘turn-off’ all the particles from the sun except neutrinos for a short period of time,” Lee said. “If we make the connection of nuclear decay rates to solar activity, it means we have found something very new.”
Morris notes that even if the series of experiments disproves the team’s theories, they will have learned something very important about the equipment scientists use to monitor nuclear decays. That, in turn, may shed light on a number of inconsistencies found in half-life values published across scientific literature.
The team is planning two additional experiments after Kadena, including an experiment at the underground particle detector at San Grasso National Lab, near L’Aquila, Italy. Other team members include two Purdue University ROTC cadets, two Air Force Academy cadets, and an Air Force Academy graduate from the Class of 2009.
This research was made possible with the support of the Air Force Office of Scientific Research International Programs Office and Air Force Air Mobility Command.
For information on the solar eclipse, visit: www.examiner.com/x-12640-Holistic-Travel-Examiner~y2009m7d5-Total-Solar-Eclipse-July-22-2009-Best-places-on-Earth-to-view.