Cosmic Rays May Threaten Future Deep-Space Astronaut Missions to Mars
When it comes to sending a man to Mars, NASA is faced with a host of challenges. Now, scientists are beginning to understand exactly how severe these challenges may be. They've found that cosmic rays may threaten future deep-space astronaut missions with hazardous radiation.
In this case, the researchers examined the sun, which is the source of much of Earth's space weather. The scientists found that due to a highly abnormal and extended lack of solar activity, the solar wind is exhibiting extremely low densities and magnetic field strengths, which causes dangerous levels of hazardous radiation to pervade the environment of space.
"The behavior of the sun has recently changed and is now in a state not observed for almost 100 years," said Nathan Schwadron, one of the researchers, in a news release. Usually the sun keeps to an 11-year solar cycle, followed by two to three-year periods where the sun is more active. "However, starting in about 2006, we observed the longest solar minimum and weakest solar activity observed in the space age."
These conditions in particular have caused the highest intensities of galactic cosmic rays seen since the beginning of the space age. This, in turn, worsens hazardous radiation levels, which could threaten future deep-space missions with astronauts.
"While these conditions are not necessarily a showstopper for long-duration missions to the moon, an asteroid, or even Mars, galactic cosmic ray radiation in particular remains a significant and worsening factor that limits mission durations," said Schwadron. "These data are a fundamental reference for the radiation hazards near Earth 'geospace' out to Mars and other regions of our sun's vast heliosphere."
The findings reveal the importance of taking radiation into account when planning long space missions to other planets. It's possible that spacecraft could be designed to lessen the effects of this radiation, and allow astronauts to stay in space for longer.
The findings are published in the journal Space Weather.