Man’s quest to travel into deep space and colonize Mars is a brave undertaking, and the dangers are great. One of the biggest questions we need to answer is how we will deal with the space radiation on Mars?
Here on Earth, we are protected from space radiation by our atmosphere and the Earth’s magnetic field. On Mars, humans would be essentially naked and helpless against the cosmic radiation that bombards the Martian surface.
In a NASA funded study to determine what effects a journey into deep space might have on the health of astronauts, cancer researchers at Georgetown University Medical Center (GUMC) used mice to test exposure to heavy ion radiation – meant to mirror galactic cosmic radiation exposure to astronauts.
The GUMC study, published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS), suggests that deep space bombardment by galactic cosmic radiation (GCR) could significantly damage gastrointestinal (GI) tissue leading to long-term functional alterations, and raises concerns about the high risk of tumor development in the stomach and colon.
While all this may sound complicated, basically, scientists compared space radiation to X-ray radiation and found the effects of space radiation are far more dangerous, according to CNN.
Studying ionizing radiation
GUMC researchers studied the effects of ionizing radiation, a type of radiation found in space and considerably different from radiation on Earth. This GCR or galactic cosmic radiation consists of beams of high-energy particles with so much energy they can knock the electrons and protons off of atoms.
In this case, in the study, the researchers used heavy iron (56Fe) ions in their experiments at the NASA Space Radiation Laboratory, bombarding mice with a low dose, comparable with what astronauts would experience on a trip to Mars.
Long exposures to a low dose of galactic radiation left the mice with permanent damage to their gastrointestinal tracts and they could no longer absorb nutrients in food. The mice also developed cancerous growths in their intestines — raising concerns that astronauts who venture far into space would face the same deadly health issues.
“While short trips, like the time’s astronauts traveled to the moon, may not expose them to this level of damage, the real concern is the lasting injury from a long trip,” said Kamal Datta, head of Georgetown’s NASA Specialized Center of Research, in a press release.
And there is a huge difference in going to the Moon, which takes about three days – and going to Mars, which could take nine months. And here’s the concern – We have not developed any medicines that can reverse permanent organ damage caused by radiation. And preventing the radiation exposure in the first place is also difficult.
GCR is not like X-rays on Earth. Technicians can shield our bodies with a protective blanket so certain parts don’t absorb the radiation. But we have no equivalent technology to protect astronauts in space.
“We have documented the effects of deep space radiation on some vital organs, but we believe that similar damage responses may occur in many organs,” says Datta. “It is important to understand these effects in advance so we can do everything we can to protect our future space travelers.”
