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Study: Space radiation threats to astronauts UNIVERSITY OF COLORADO-BOULDER NEWS RELEASE Posted: October 25, 2006 A better understanding of solar storms and how best to protect astronauts from space radiation is needed as NASA pushes toward manned missions to the moon and Mars in the coming decades, according to a new National Research Council report. Researchers have been stepping up studies on radiation biology and space shielding in recent years, said the University of Colorado at Boulder's Daniel Baker, chair of the committee that issued an NRC report this week titled, "Space Radiation Hazards and the Vision for Space Exploration." The report probes the physical risks and technology obstacles of extended space journeys and is tied to a 2004 presidential mandate to return to the moon by 2020 and then send human travelers on to Mars, said Baker, director of CU-Boulder's Laboratory for Atmospheric and Space Physics. Baker, an internationally known space weather expert, said the report brought together space physicists and radiation biologists, amplifying common interests between the groups. "This was an important step," he said. "One of the benefits of this report is that we are beginning to lower the error bar on the health impacts of space radiation to astronauts, and are looking hard at other challenges like more accurate solar forecasting and improved space engineering techniques." Astronauts are regularly exposed to high doses of radiation, including galactic cosmic rays -- thought to come from distant supernova explosions -- as well as energetic particles from the sun and charged particles trapped in Earth's magnetic field, he said. Potential health effects include leukemia and other cancers, and degenerative tissue effects like cataracts, heart disease, digestive diseases and respiratory diseases, according to the report. Radiation also can cause damage to the central nervous system and cause acute risks like vomiting and nausea, said Baker. "One concern is that astronauts could become ill from space radiation effects and vomit in their space suits, which could be extremely serious," he said. The report noted that a violent solar storm that occurred in August 1972 between the Apollo 16 and Apollo 17 missions could have been extremely hazardous to astronauts had they been on the moon. The radiation exposure levels would have varied depending on whether the astronauts were exploring the lunar surface or were inside the landing vehicle, which would have offered more protection, said the report. "We know that this storm was large enough that it could have had potentially fatal consequences to astronauts had they been on the moon at that time," said Baker. The report also addresses the issue of "storm shelters" to protect astronauts from harmful radiation, which can be built both inside spacecraft or on the surface of the moon and Mars, Baker said. Such shelters could include cylindrical "cocoons" of thick shielding material for astronauts to crawl in or shelters lined with thick tanks filled with water, since water is not only essential for space travel but also contains large amounts of hydrogen, a proven buffer for mitigating harmful radiation, he said. Plastic polymers containing large amounts of hydrogen also might be a potentially useful building material for shielding, according to the report. "There is always the possibility that a spacecraft can be blasted by significant doses of radiation, and we need to take that into account when designing spacecraft," he said. Soils on the moon and Mars also could be used to build efficient shelters from solar storms, especially if astronauts were on extended expeditions putting them hours away from base camps or space vehicles, Baker said. The report recommends creating a "color-coded alert system" for intense solar events that could be transmitted quickly to astronauts roaming alien soils, he said. A workshop on the issues -- co-sponsored by NASA, the National Science Foundation and the National Research Council -- was held Oct. 16 to Oct. 20 in Wintergreen, Va. In September, NASA selected 12 radiation biology proposals for funding that target reduction of health and safety risks for astronauts, said Baker. The National Research Council is a federal organization created by the National Academy of Sciences in 1916 to bring together the American science and technology community to advance knowledge and advise the federal government. |
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Some of the initial pictures and data from NASA's Mars Reconnaissance Orbiter since the craft entered its mapping orbit around the Red Planet are presented in this news briefing held October 16 from the Jet Propulsion Laboratory.
The three-man Expedition 14 crew of the International Space Station complete a short trip, flying their Soyuz capsule to another docking port in preparation for receiving a resupply ship.
Space shuttle Discovery's STS-39 flight, launched in April 1991, served as a research mission for the U.S. Department of Defense. An instrument-laden spacecraft for the Strategic Defense Initiative Organization was released to watch Discovery perform countless rocket firings and maneuvers, as well as canisters releasing clouds of gas. The crew tells the story of the mission in this post-flight film presentation.
Seeking to study explosive forces across the universe, the Gamma Ray Observatory was launched aboard shuttle Atlantis in April 1991. But when the craft's communications antenna failed to unfold, spacewalking astronauts ventured outside the shuttle to save the day. The rescue EVA was followed by a planned spacewalk to test new equipment and techniques. The crew of STS-37 narrate this post-flight mission film.
Dazzling images from Mars are revealed by scientists. The robotic rover Opportunity has reached the massive Victoria crater with its steep cliffs and layers of rock exposing the planet's geologic history. Meanwhile, the new Mars Reconnaissance Orbiter has photographed the rover and its surroundings from high above.
n this news conference from NASA Headquarters, scientists announce the Hubble Space Telescope's discovery of 16 extrasolar planet candidates orbiting a variety of distant stars in the central region of our Milky Way galaxy. Five of the newly found planets represent a new extreme type of planet not found in any nearby searches.