Study: Mars Missions Should Be Limited to 4 Years to Protect from Radiation
2021-09-06
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1A new study has found that future missions to Mars should be limited to four years to protect astronauts from harmful radiation.
2The study also says that missions should be carried out during specific times to reduce the level of exposure to dangerous particles.
3The U.S. space agency NASA currently has plans to send astronauts back to the moon.
4It also plans to one day send astronauts to Mars.
5Those plans include missions that would keep astronauts in space for long periods.
6China has also announced plans to send astronauts to Mars by 2033.
7Such missions present great risks to humans because of the high level of radiation in space.
8Radiation exposure can cause a series of health issues, including skin burns, heart problems and cancer.
9NASA has spent many years studying ways to protect human space travelers from radiation.
10On Earth, we also experience exposure to radiation from the sun.
11But our planet's magnetic field protects us from dangerously high levels.
12Two main kinds of radiation can affect humans and equipment in space.
13 One is produced by particles released from the sun.
14The other comes from high energy particles created by cosmic rays from outside our solar system.
15NASA says the second kind can be more dangerous to humans and more destructive to equipment.
16In the new study, researchers used modeling methods to predict levels of radiation exposure during future space missions.
17They combined geophysical models of particle radiation with models for how radiation would affect human passengers and spacecraft.
18The international group of researchers recently published their study in Space Weather.
19The results showed that the best time for a human space flight to Mars would be during what is known as solar maximum.
20This is a period within the sun's magnetic cycle that experiences the most intense solar activity.
21The researchers said in a statement that this period would be a good time for a flight because, "the most dangerous and energetic particles from distant galaxies are deflected by the enhanced solar activity," during solar maximum.
22The study also found that a round-trip mission to Mars should not last longer than four years.
23A longer mission would expose astronauts to "dangerously high" amounts of radiation, even if the trips to and from Mars were made during safer travel times.
24The average flight time to Mars is about nine months.
25The spacecraft used for carrying astronauts to Mars would require special protective shielding, the study found.
26But the researchers said this protective material cannot be too heavy.
27If the material is too thick, it could actually increase the amount of secondary radiation the astronauts could be exposed to.
28The research team included scientists from the University of California, Los Angeles (UCLA).
29UCLA research geophysicist Yuri Shprits was a co-writer of the study.
30He said the findings suggest that future missions to Mars can be safe for humans as long as they follow the research recommendations.
31Shprits said, "This study shows that while space radiation imposes strict limitations on how heavy the spacecraft can be and the time of launch -- and it presents technological difficulties for human missions to Mars -- such a mission is viable."
32NASA is currently working to develop several kinds of solutions to protect humans serving long-term space missions.
33Possible solutions include building temporary shelters, developing high-tech protective clothing, or deploying special shields above Mars to block radiation.
34I'm Bryan Lynn.
1A new study has found that future missions to Mars should be limited to four years to protect astronauts from harmful radiation. 2The study also says that missions should be carried out during specific times to reduce the level of exposure to dangerous particles. 3The U.S. space agency NASA currently has plans to send astronauts back to the moon. It also plans to one day send astronauts to Mars. Those plans include missions that would keep astronauts in space for long periods. 4China has also announced plans to send astronauts to Mars by 2033. Such missions present great risks to humans because of the high level of radiation in space. 5Radiation exposure can cause a series of health issues, including skin burns, heart problems and cancer. NASA has spent many years studying ways to protect human space travelers from radiation. 6On Earth, we also experience exposure to radiation from the sun. But our planet's magnetic field protects us from dangerously high levels. 7Two main kinds of radiation can affect humans and equipment in space. One is produced by particles released from the sun. The other comes from high energy particles created by cosmic rays from outside our solar system. NASA says the second kind can be more dangerous to humans and more destructive to equipment. 8In the new study, researchers used modeling methods to predict levels of radiation exposure during future space missions. They combined geophysical models of particle radiation with models for how radiation would affect human passengers and spacecraft. 9The international group of researchers recently published their study in Space Weather. The results showed that the best time for a human space flight to Mars would be during what is known as solar maximum. This is a period within the sun's magnetic cycle that experiences the most intense solar activity. 10The researchers said in a statement that this period would be a good time for a flight because, "the most dangerous and energetic particles from distant galaxies are deflected by the enhanced solar activity," during solar maximum. 11The study also found that a round-trip mission to Mars should not last longer than four years. A longer mission would expose astronauts to "dangerously high" amounts of radiation, even if the trips to and from Mars were made during safer travel times. The average flight time to Mars is about nine months. 12The spacecraft used for carrying astronauts to Mars would require special protective shielding, the study found. But the researchers said this protective material cannot be too heavy. If the material is too thick, it could actually increase the amount of secondary radiation the astronauts could be exposed to. 13The research team included scientists from the University of California, Los Angeles (UCLA). UCLA research geophysicist Yuri Shprits was a co-writer of the study. He said the findings suggest that future missions to Mars can be safe for humans as long as they follow the research recommendations. 14Shprits said, "This study shows that while space radiation imposes strict limitations on how heavy the spacecraft can be and the time of launch -- and it presents technological difficulties for human missions to Mars -- such a mission is viable." 15NASA is currently working to develop several kinds of solutions to protect humans serving long-term space missions. Possible solutions include building temporary shelters, developing high-tech protective clothing, or deploying special shields above Mars to block radiation. 16I'm Bryan Lynn. 17Bryan Lynn wrote this story for VOA Learning English, based on reports from UCLA, Space Weather and NASA. Ashley Thompson was the editor. 18We want to hear from you. Write to us in the Comments section, and visit our Facebook page. 19_________________________________________ 20Words in This Story 21mission - n. an important task, usually involving travel 22specific - adj. clearly defined or identified 23exposure - n. coming into contact with something 24cosmic ray - n. high-energy particles that move through space at nearly the speed of light 25maximum - n. the greatest or highest amount possible 26deflect - v. to make something change direction by hitting or touching it 27enhance - v. to improve something 28shield - n. a piece of equipment used as protection 29impose - v. to put or place 30viable - n. effective and able to be successful