Aluminum has always been the primary material in spacecraft construction, but it provides relatively little protection against high-energy cosmic rays and can add so much mass to spacecraft that they become cost-prohibitive to launch.
The scientists have published their findings online in the American Geophysical Union journal Space Weather. Titled "Measurements of Galactic Cosmic Ray Shielding with the CRaTER Instrument," the work is based on observations made by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on board the LRO spacecraft. Lead author of the paper is Cary Zeitlin of the SwRI Earth, Oceans, and Space Department at UNH. Co-author Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space is the principal investigator for CRaTER.
Says Zeitlin, "This is the first study using observations from space to confirm what has been thought for some time—that plastics and other lightweight materials are pound-for-pound more effective for shielding against cosmic radiation than aluminum. Shielding can't entirely solve the radiation exposure problem in deep space, but there are clear differences in effectiveness of different materials."
The plastic-aluminum comparison was made in earlier ground-based tests using beams of heavy particles to simulate cosmic rays. "The shielding effectiveness of the plastic in space is very much in line with what we discovered from the beam experiments, so we've gained a lot of confidence in the conclusions we drew from that work," says Zeitlin. "Anything with high hydrogen content, including water, would work well."
The space-based results were a product of CRaTER's ability to accurately gauge the radiation dose of cosmic rays after passing through a material known as "tissue-equivalent plastic," which simulates human muscle tissue. Prior to CRaTER and recent measurements by the Radiation Assessment Detector (RAD) on the Mars rover Curiosity, the effects of thick shielding on cosmic rays had only been simulated in computer models and in particle accelerators, with little observational data from deep space.
The CRaTER observations have validated the models and the ground-based measurements, meaning that lightweight shielding materials could safely be used for long missions, provided their structural properties can be made adequate to withstand the rigors of spaceflight.
Since LRO's launch in 2009, the CRaTER instrument has been measuring energetic charged particles—particles that can travel at nearly the speed of light and may cause detrimental health effects—from galactic cosmic rays and solar particle events. Fortunately, Earth's thick atmosphere and strong magnetic field provide adequate shielding against these dangerous high-energy particles.The NASA Goddard Space Flight Center in Greenbelt, Md. developed and manages the LRO mission. LRO's current science mission is implemented for NASA's Science Mission Directorate. NASA's Exploration Systems Mission Directorate sponsored LRO's initial one-year exploration mission that concluded in September 2010.
For more on the CRaTER instrument, visit http://crater.sr.unh.edu/ and for the LRO mission visit http://lunar.gsfc.nasa.gov/mission.html.
The University of New Hampshire, founded in 1866, is a world-class public research university with the feel of a New England liberal arts college. A land, sea, and space-grant university, UNH is the state's flagship public institution, enrolling 12,200 undergraduate and 2,300 graduate students.
Image to download:
Caption: Artist's conception of NASA's Lunar Reconnaissance Orbiter above the Moon. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument is visible in the center of the image at the bottom left corner of the spacecraft. Image courtesy of NASA.
David Sims | EurekAlert!
3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg
Better equipped in the fight against lung cancer
16.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy