Remember Spirit, the lonely rover that drove around on the surface of Mars for years past its mission end date? Well, it seems its bigger brother Curiosity might have thrown a spanner in the works in regards to a human settlement on Mars, or interplanetary travel in general. At a news conference yesterday, NASA presented new findings from the Mars Science Laboratory Radiation Assessment Detector (RAD) aboard Curiosity, showing that astronauts on a trip to Mars would be subjected to a dose of radiation nearly equal to their career limit. Auch.
Over their career, NASA limits astronauts’ increased risk of cancer and central nervous system damage to 3 percent. That translates to a cumulative radiation dose of between about 800 millisieverts and 1,200 millisieverts, depending on a person’s age, gender and other factors. Results from Curiosity indicate that astronauts would receive a radiation dose of about 660 millisieverts during a 360-day roundtrip flight – and that’s calculated according to the fastest travel possible with today’s chemical rockets. To put that dose in context, an astronaut circling orbit on the International Space Station for 6 months, would receive about 100 millisieverts.
So what’s next? Well, one possible avenue that will need to be explored is how to shield astronauts from the bombardment by radiation from cosmic rays and solar outbursts. Another avenue would be to speed up the journey by developing the next generation of propulsion systems. And what about putting all the engineering challenges aside for a minute, and looking at the human body, what if some day we could just counter that damage with our own DNA…
Whatever road we take, it seems like we shouldn’t be packing our bags for Mars just yet…