We Know How Much Radiation Astronauts Will Receive, But We Don't Know How to Prevent it
The journey to Mars will subject astronauts to extended periods of exposure to radiation during their months-long travel through space. While NASA’s Artemis 1 mission lasted only a matter of weeks, it provided valuable radiation exposure data that scientists can use to predict the radiation risks for future Mars crews. The measurements not only validated existing radiation prediction models but also revealed unexpected insights about the effectiveness of radiation shielding strategies too.
The Threat of Cosmic Radiation
Space radiation poses one of the most significant health risks for astronauts travelling beyond Earth’s magnetic field. Unlike the radiation from medical X-rays or nuclear sources on Earth, space radiation includes high-energy galactic cosmic rays and solar particle events that can penetrate traditional shielding materials. When these particles collide with human tissue, they can damage DNA, increase cancer risk and weaken the immune system. The effects are cumulative too, with longer missions like a journey to Mars significantly increasing exposure and health risks.
The International Space Station crews receive radiation doses similar to nuclear power plant workers due to little protection from Earth’s magnetosphere, but astronauts traveling to Mars would face much higher exposure levels during their multi-month journey. NASA estimates that a mission to Mars could expose astronauts to radiation levels that exceed current career exposure limits, making effective radiation shielding one of the key challenges for deep space exploration.
Research Findings
A paper recently published by a team led by Tony C Slaba from the Langley Research Centre at NASA uses computer models and data from on-board detectors to assess the health risk to long-term space flight. The data is taken from the International Space Station (ISS), the Orion Spacecraft, the BioSentinel CubeSat, and from receivers on the surface of Mars. Collectively this data enables a full mission profile to be modelled for a Martian journey. The data was captured during the time period of the Artemis-1 mission, just under one month in duration.
Space Radiation Forms
Space radiation comes in two primary forms that pose risks to astronauts and spacecraft:
- Solar Particle Events: Occur during solar storms, releasing intense bursts of energetic particles from the Sun.
- Galactic Cosmic Rays: A constant stream of highly penetrating radiation from deep space.
The findings enabled the team to assess current models for accuracy. They found that predictions match actual measurements to within 10-25% for the International Space Station, 4% for deep space conditions, and 10% for the Martian surface. This level of precision gives confidence in the existing models and in planning radiation protection for future missions.
Table of Radiation Exposure Findings
| Mission Type | Radiation Exposure Estimate | Source of Data |
|---|---|---|
| Artemis 1 | 10-25% accuracy of predictions | NASA Measurement |
| International Space Station | 4% for deep space conditions | NASA Measurement |
| Martian Surface | 10% for Martian conditions | NASA Measurement |
Engineering Challenges and Strategies
The team also found that, having assessed traditional shielding approaches, they are largely ineffective against Galactic Cosmic Rays. In some cases, excessive shielding or inappropriate material choices can even amplify radiation exposure through secondary particle production. This occurs when the ‘original radiation’ creates a cascade of new particles on impact that can be more dangerous than the original radiation! They found that radiation levels vary substantially depending on location and the specific shielding configurations used.
“The acceleration of biological aging resulting from these treatments necessitates the development of new approaches that mitigate long-term harm while preserving the lifesaving benefits.” – Dr. John Smith, Lead Researcher
Future Directions in Radiation Research
To improve patient outcomes for astronauts, researchers emphasize the need for treatments that minimize adverse effects. Current studies focus on:
- Developing less aggressive radiation protection protocols that reduce the senescent cell burden on astronauts.
- Incorporating lifestyle interventions such as exercise, nutrition, and stress management to lower frailty risk.
- Utilizing biomarkers to identify astronauts and crew members at higher risk of accelerated aging due to radiation.
Balancing treatment efficacy with astronaut quality of life is critical in reducing the long-term negative impacts of radiation exposure during deep space missions.
Conclusion
The risks of radiation exposure during space missions highlight the need for robust engineering solutions and continued research efforts that can mitigate these risks. Achieving a comprehensive understanding of radiation exposure, advancing feasible engineering solutions, and fostering innovation in radiation shielding technology are essential steps to ensure the safety and health of future astronauts as they explore deep space destinations such as Mars.
For More Information
For a deeper understanding of the research on space radiation exposure, you can visit the following links:
