Radiation measurements sent back from NASA's Mars Science Laboratory mission as it delivered the rover Curiosity to Mars last year is giving scientists the information they need to protect astronauts on future deep space missions.
NASA researchers will use the radiation measurements to design protective systems to shield humans from radiation exposure on deep-space expeditions, such as planned journeys to Mars.
Initial research into the measurements shows that the radiation exposure on a trip to Mars, using current shielding technology, would exceed NASA's career limit for its astronauts.
A 3% increased risk of fatal cancer is now NASA's limit for astronauts traveling and working in low-Earth orbit.
"As this nation strives to reach an asteroid and Mars in our lifetimes, we're working to solve every puzzle nature poses to keep astronauts safe so they can explore the unknown and return home," said William Gerstenmaier, NASA's associate administrator for human exploration and operations, in a written statement. "Curiosity's Radiation Assessment Detector is giving us critical data we need so that we humans, like the rover, can dare mighty things to reach the Red Planet."
Gerstenmaier added that NASA engineers and scientists will be using Curiosity's radiation measurements as they continue to work on the Orion spacecraft and the Space Launch System rocket to carry and shelter astronauts in deep space.
NASA noted that the radiation detector onboard the Mars Science Laboratory was the first instrument set up to measure the radiation inside the spacecraft during a journey to the Red Planet. The environment inside the rover's spacecraft is similar to what humans might experience in a capsule.
The measurements, NASA reported, will decrease uncertainty about the effectiveness of current radiation shielding.
There are two kinds of radiation that pose potential health risks to astronauts in deep space, NASA said. One is galactic cosmic rays, which are particles caused by supernova explosions and other high-energy events outside the solar system. The other is solar energetic particles, which are associated with solar flares and coronal mass ejections from the sun.
"These measurements will be used to better understand how radiation travels through deep space and how it is affected and changed by the spacecraft structure itself," said NASA researcher Donald M. Hassler, in a statement. "The spacecraft protects somewhat against lower energy particles, but others can propagate through the structure unchanged or break down into secondary particles."
The rover, which is equipped with multiple scientific instruments, is working to find evidence of whether Mars does -- or has ever been able to -- sustain life, even in microbial form.