Bad news, everyone: The Curiosity rover has taken new radiation readings that reveal that a trip to Mars would effectively fry you with radiation.
According to new radiation data taken by Curiosity's Radiation Assessment Detector (RAD) as the interplanetary drone made its way to Mars, astronauts traveling to the red planet would be subjected to radiation levels high enough to retire them just after one mission. As Cary Zeitlin, a principal scientist at the Southwest Research Institute, explained it in a release, "in terms of accumulated dose, it's like getting a whole-body CT scan once every five or six days."
Scientists measure radiation exposure in units of Sieverts, and according to NASA, an accumulated dose of one Sievert over a long period of time increases your chances of developing a fatal cancer by five percent. By comparison, NASA's current standards "[have] established a three percent increased risk of fatal cancer as an acceptable career limit" for its astronauts orbiting around Earth.
Curiosity's RAD data recorded an average daily exposure of 1.8 millisieverts during its journey to Mars. Using current propulsion systems, it would take 253 days to get an astronaut crew to Mars, which would expose them to approximately 455 millisieverts (.0445 sieverts) of radiation. That's nearly half the career limit of radiation exposure for astronauts in low-Earth orbit, and that's just the one-way trip without taking into account any additional exposure there will be on Mars, much less the return trip to Earth.
It's also important to note that the radiation Curiosity encountered mostly came in the form of galactic cosmic rays (GCRs) that are released by supernova explosions and other high-energy events outside the solar system.
Meanwhile, only about three percent of the radiation dose came from our own Sun as solar energetic particles (SEPs), which are released regularly through solar flares and coronal mass ejections. So if the sun is particularly active during our astronauts' trip to Mars, then the radiation exposure could be even higher.
NASA scientists say that current spacecraft shielding is much more effectively against our own Sun's radiation rather than GCRs. To protect our space travelers, researchers are looking into developing extra-shielded havens within the spacecraft. Alternatively, NASA is also looking into improving the propulsion systems to make the trip just go faster.
If you want to read more about the findings, they are published in the May 31 edition of the journal Science.