When Stan Lee needed something to threaten his Fantastic Four’s mission to beat the Commies into space, he picked cosmic rays.
And although he probably picked that just because it sounded cool, maybe Stan was on to something. Although cosmic rays (probably) won’t turn you into a guy made of orange rocks, scientists say they may be an increasingly dangerous threat to deep space travel missions just the same.
Cosmic rays are high energy radiation that comes from outside the solar system. They’re dangerous to people and electronics under any conditions, but a recent decrease in the solar activity has caused reduced solar wind and magnetic field strength, which means stronger, deadlier cosmic rays in our solar system.
“The behavior of the sun has recently changed and is now in a state not observed for almost 100 years,” says associate professor Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space (EOS).
Schwadron is the lead author of a paper that addresses the problem. He’s also principal investigator for the Cosmic Ray Telescope for the Effects of Radiation (CRaTER), which is fitted on NASA’s Lunar Reconnaissance Orbiter (LRO) launched in 2009.
Through the space age the sun has been on a nearly clockwork 11-year activity, cycle, Schwadron said, with six to eight year lulls followed by two to three year active periods.
“However, starting in about 2006, we observed the longest solar minimum and weakest solar activity observed in the space age,” Schwadron said.
The cosmic rays can cause electronics to malfunction. They can also cause radiation sickness, cancer and organ damage in humans. Using data from the CraTER project scientists estimate that even with shielding humans will be able to spend 20 percent less time in space during this solar minimum cycle than the last one.
“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,” Schwadron said.
[Source: University of New Hampshire]
Image of Orion Spacecraft concept via NASA.gov