Up, Up, and Away: Victor Hess and the Cosmic RayANS Nuclear CafeAugust 17, 2011, 6:00AM|Paul BowersoxVictor Francis Hess was awarded a Nobel Prize in physics for discovering "cosmic rays." Hess did some of his research in a very bold manner-here's some of his story.A strange case of atmospheric ionizing radiationIonizing radiation is very potent, as radiation goes, because it has sufficient energy to knock electrons off of atoms or molecules-thus producing positively-charged ions. Ions can also be negatively-charged, such as when a free electron is caught by an atom or molecule-and ions can even be formed by adding other ions.This "ionizing radiation" was known and measurable in the early 1900s, but the results of some measurements were not as expected. The newly-invented instruments of the time-electrometers, which could detect the presence of energetic charged particles-had been used to detect many radiation sources at ground level. Naturally, moving away from these ground-based radiation sources should have resulted in lower electrometer readings.Instead, early experiments, such as Theodor Wulf's taking his new electrometer to the top of the Eiffel Tower, seemed to indicate that ionizing radiation in the atmosphere increased at levels above the (radioactive) ground. These results were definitely not well accepted by scientific authorities at the time.Enter Victor HessHessVictor Hess was very interested in this puzzle. He improved the accuracy and endurance of Wulf's electrometer, then put this new equipment to good use by taking measurements of charged particles in the atmosphere-from the gondola of a balloon! These were no ordinary balloon excursions. Both during the day and night, in 1911 and 1912, Hess measured ionizing radiation at altitudes up to 3 miles high. A risky endeavor at the time.Hess's work showed that, as one ascended above the surface of the earth, the level of radiation at first decreased just as expected. Then, radiation levels began to increase with increasing altitude-reaching several times that of ground level at Hess's maximum attainable altitude of about 3 miles.Hess and his balloonHess even made an ascent during a solar eclipse, to rule out the sun as the source of the radiation. With the moon blocking most of the sun's radiation, levels of radiation in the atmosphere still increased at higher altitudes. Hess could only conclude that the atmospheric radiation came from outer space, and eventually came to be known as cosmic rays.Cosmic raysMost cosmic rays are actually protons (hydrogen nuclei without an electron), while about 10 percent are alpha particles (helium nuclei without electrons), 1 percent are heavier charged particles, and most of the remainder are solitary electrons. Also, a small fraction of cosmic rays are antimatter particles.The earth's atmosphere does a good job of protecting us on the surface from cosmic rays-and this is fortunate, since some cosmic rays have energies much greater than can even be created with the largest particle accelerators. Cosmic rays interact in the atmosphere to create secondary radiation, including x-rays, muons, protons, alpha particles, pions, electrons, and neutrons. In spite of the atmosphere's shielding, cosmic rays are still a substantial portion of the natural background radiation that the earth experiences every day.The effects of cosmic rays explain why airline flight crew workers receive more radiation dose on average than any other worker. Fortunately, for eons our distant ancestors flourished in our (mildly) radioactive environment on earth-equipped with the ability to successfully repair the occasional damage from ionizing radiation. To estimate your own overall radiation dose rate, click the interactive ANS Radiation Dose chart.Some of the sources of cosmic rays are well understood, including processes occurring in other stars like our sun. Other sources of cosmic rays are unknown and a matter of ongoing research. Hess's discovery of cosmic rays led to an era of new discoveries in particle physics that still continues. After receiving his Nobel Prize in 1936, he continued a long and outstanding career of research into nuclear physics, radioactivity, and its effects.BowersoxPaul Bowersox is a fan of ballooning and a contributor to ANS Nuclear Cafe.Tags:irradiationnuclear pioneersphysicsradiationShare:LinkedInTwitterFacebook
Farming in FukushimaScreenshot of the video from Vice. Vice News has published a video on YouTube that follows two farmers from the Fukushima Prefecture, Noboru Saito and Koji Furuyama. Saito, who grows many different crops on his farm, says that the rice grown in the area is consistently rated as the best. Furuyama specializes in peaches and explains his strategy to deal with the stigma of selling fruit from Fukushima: grow the best peaches in the world.Go to Article
The Toxic Pigs of Fukushima kicks off an online documentary seriesA film titled The Toxic Pigs of Fukushima gets top billing as part of The Short List with Suroosh Alvi, an online documentary series curated by the founder of the media company Vice. The film, which first aired on Vice TV on January 31, follows local hunters who have been enlisted to dispose of radiated wild boars that now roam abandoned streets and buildings in Fukushima Prefecture, Japan, in the aftermath of the 2011 earthquake and tsunami that caused the nuclear accident there.Go to Article
LA Times asks, “How safe is the water off SONGS?”A California surfer. Photo: Brocken Inaglory/WikicommonsThe Los Angeles Times published an article on December 1 about a recent collaboration between the Surfrider Foundation and the Woods Hole Oceanographic Institution to determine how safe the water is off the coast of the San Onofre Nuclear Generating Station (SONGS).Go to Article
White paper shines light on significance of irradiationWith input from the American Nuclear Society and other organizations, the International Irradiation Association has published a white paper summarizing all of the significant uses of radiation processing and the global economic, social, and environmental benefits that arise from the technologies. The nontechnical document, Uses and Applications of Radiation Processing, is aimed at people and organizations that are not familiar with radiation processing, highlighting how irradiation is routinely used in an array of diverse and beneficial applications.“Though largely unknown by the public, radiation processing, or ‘irradiation,’ touches everyone’s life,” states the paper, which was released on November 24.The 11-page white paper goes on to summarize the applications of radiation processing, including medical sterilization, food irradiation, wastewater treatment, and other uses. An overview of the different technologies used to irradiate materials, including gamma, electron beam, and X-ray sources, is also provided.Go to Article
Nuclear power: Are we too anxious about the risks of radiation?RowlattFollowing U.K. Prime Minister Boris Johnson’s recent restatement of the United Kingdom’s commitment to nuclear power, BBC News chief environment correspondent, Justin Rowlatt, wrote an article aimed at separating fact from fiction regarding the safety and benefits of nuclear energy.Among his points, Rowlatt defended the use of nuclear power to combat climate change, examined the data behind deaths from radiation exposure directly caused by the Chernobyl and Fukushima accidents, and explained that exposure to low levels of radiation is not a major health risk.Go to Article
Harnessing the promise of radiation: The art of reasonablenessRadiation has benefited mankind in many ways, including its use as an energy source and an indispensable tool in medicine. Since the turn of the 20th century, society has sought ways to harness its potential, while at the same time recognizing that radiological exposures need to be carefully controlled. Out of these efforts, and the work of many dedicated professionals, the principles of justification, optimization, and limitation have emerged as guiding concepts.Justification means that the use of radiation, from any radiation source, must do more good than harm. The concept of optimization calls for the use of radiation at a level that is as low as reasonably achievable (ALARA). Dose constraints, or limitation, are meant to assist in reaching optimization and protection against harm by setting recommended numerical levels of radiation exposure from a particular source or sources. Together, these three principles form the bedrock of the international radiation protection system that drives decision-making and supports societal confidence that radiation is being used in a responsible manner.Go to Article
Low-dose radiation has found its analogueCraig PiercyOriginally published in the September 2020 issue of Nuclear News.This issue of Nuclear News is dedicated to highlighting advancements in health physics and radiation protection as well as the contributions of the men and women who serve in these fields. It comes at a time when COVID-19 is providing the entire world with an immersive primer on the science of epidemiology and the importance of risk-informed, performance-based behavior to contain an invisible—yet deadly—antagonist.Go to Article
Piercy discusses wide-ranging topics on Titans of Nuclear podcastANS Executive Director/CEO Craig Piercy was a recent guest on the Titans of Nuclear podcast, hosted by Bret Kugelmass. The podcasts feature interviews with experts throughout the nuclear community, covering advanced technology, economics, policy, industry, and more.The wide-ranging discussion with Piercy tackled diverse subjects—from his Washington, D.C., policymaking background, to ANS’s role in addressing challenging nuclear issues, to waste management and climate change.Go to Article
Elettra designated an IAEA collaborating centerA collaborating center agreement was signed by Elettra Sincrotrone Trieste and the International Atomic Energy Agency in May. The agreement focuses on advanced light sources and will support countries in research, development, and capacity building in the application of advanced and innovative radiation technologies.Go to Article
Fact-checking Amazon's new season of BoschThe latest season of Amazon’s detective series Bosch premiered recently on its streaming service, Prime. The season opens with the murder of a medical physicist and the theft of radioactive cesium, with plenty of drama following as the protagonist tries to solve the murder and end the “catastrophic threat to Los Angeles.” The show is a work of fiction, but let’s take a closer look at the depiction of radiation to sort out the scientific facts.The setup: The series stars Titus Welliver as Los Angeles Police Department detective Harry Bosch and Jamie Hector as his partner, Jerry Edgar. The first episode of the sixth and latest season begins late in the evening at a Los Angeles hospital. We are shown a nervous-looking medical physicist as he walks into a laboratory, the camera dramatically focusing on the radiation sign on the door. No one else is around as the medical physicist clears out the lab’s inventory of what we find out later is cesium. The physicist then walks the material out of the hospital without anyone giving him a second look.Go to Article