As particles from the sun and high-energy cosmic radiation stream constantly into their bodies, astronauts are always in danger.
Radiation can cause serious health problems if it is not controlled. It can increase the risk of cancer in astronauts. NASA uses radiation exposure caps to limit the time astronauts can remain in space. NASA is working with independent experts to improve the radiation exposure cap.
NASA currently calculates the cap using a risk estimate. Based on the available data, the limit is the maximum amount of exposure that would give astronauts a 3% greater chance of dying from cancer over the course of their lives.
Related: Future Mars-bound astronauts will face major obstacles due to radiation
The risk of developing cancers from radiation is dependent on age and the health of the reproductive organs. Space time limits don't allow for equal amounts. NASA's women cannot spend as much time in space as NASA's men. Younger astronauts are not allowed to stay up as long as their older counterparts who have less time for cancer development. Although it isn't binary, there is ample data.
NASA had previously considered changing the system to a cap that would limit astronauts' exposures to the risk limit applied to the most vulnerable, a 35-year old woman. A committee of the National Academies of Sciences, Engineering, and Medicine now supports NASA's proposal.
That's 600 million dollars in hard units over the course of a career at the agency. Comparatively, a single chest radiograph at your doctor's office will give you about 0.1 millisieverts. Earth's natural background radiation gives off around 3 millisieverts each year. In 1986, workers near Chernobyl's site zero were flooded with 6,000 millionisieverts.
According to the report, an astronaut can be exposed to 50 to 120 millisieverts for six months on the International Space Station. Expositions to distant destinations such as Mars are greater.
According to the report, the limit proposed would make younger astronauts more susceptible to radiation than older ones and decrease the time they can spend in orbit.
The 2014 update of NASA's radiation standards was made in 2014. Space.com was told by Dr. Carol Scott-Conner from the University of Iowa, who was a member of the NAS committee. "A lot has happened since then, in terms of understanding radiation biology."
Many radiation exposure standards are based upon historical studies of survivors of the 1945 atomic bombs that were dropped on Hiroshima, Nagasaki and Nagasaki. This data is being supplemented by newer data from workers in radiation-heavy fields like nuclear medicine or nuclear power.
The proposed change is not supported by everyone. Space.com's Francis Cucinotta, a radiation scientist at the University of Nevada Las Vegas who previously worked with NASA, stated that he thinks this change is dangerous. The proposal is like playing Russian roulette with female astronauts and putting them at increased radiation exposure.
Scott-Conner disagrees. She stated, "We agreed with NASA’s conclusion that it was best to set it according the standard for most vulnerable populations, which is the 35 year-old woman." She also stated that NASA's exposure limits were significantly lower than other space agencies.
Cucinotta believes that focusing on radiation-related cancer risks is a mistake. He also thinks it's wrong to focus only on heart disease. Cucinotta believes NASA should look at more data before making major changes. He said, "I don’t understand why they’re doing this now." "There is plenty of time for research in this decade for longer lunar missions and a Mars mission."
NASA is preparing to send astronauts beyond Earth's orbit with the proposed changes. Their crews won't be exposed to radiation on the first Artemis mission to the moon. For example, longer spaceflights to Mars that last months would be well beyond NASA's limitations under either system.
A waiver process would be required for astronauts who want to travel to Mars without much better radiation shielding. NASA must create a transparent and clear framework to make that happen, according to the report.
Scott-Conner stated that scientists still have much to learn about the effects of radiation from space on people. "There are many things that make a difference in surviving an atomic blast and flying to Mars.
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