Humans Heading to Mars Could Face a Disturbingly High Cancer Risk

We may earn a commission from links on this page.

Practically everyone who likes space and has lots of money is trying to get to Mars in the near future. But before anyone reaches the Red Planet, there are plenty of concerns to mull over, most notably that our bodies were not built to live in a barren litter box with a thin atmosphere. But the journey to Mars is an equal concern. An unnerving new study suggests that the trip to Mars could put passengers at a higher risk to develop cancer—possibly two times greater than what experts previously thought.

The research, led by Frank Cucinotta—a professor in department of health physics and diagnostic sciences at the University of Nevada Las Vegas—asserts that current models of cancer risk from long duration spaceflight are incomplete. For context, astronauts in space are exposed to galactic cosmic rays while they’re in space—after all, they don’t have Earth’s magnetosphere to protect them from harmful particles. These cosmic rays are concerning, since they can cause DNA damage and mutation, and obviously, the longer someone’s in space, the more they’re exposed to these particles. The team’s work has been published in the May 2017 edition of Scientific Reports.

NASA’s current risk models assert that radiation-based cancer mainly comes from cosmic rays messing with our DNA, but the team’s new model suggests the reality could be far worse. After studying tumors in mice, the researchers believe that cells damaged by cosmic rays could actually impact other healthy cells around them, like a deadly domino effect.


“Galactic cosmic ray exposure can devastate a cell’s nucleus and cause mutations that can result in cancers,” Cucinotta explained in a statement. “We learned the damaged cells send signals to the surrounding, unaffected cells and likely modify the tissues’ microenvironments. Those signals seem to inspire the healthy cells to mutate, thereby causing additional tumors or cancers.”

Worst of all, spacesuits probably won’t help much.

“Exploring Mars will require missions of 900 days or longer and includes more than one year in deep space where exposures to all energies of galactic cosmic ray heavy ions are unavoidable,” Cucinotta said in a statement. “Current levels of radiation shielding would, at best, modestly decrease the exposure risks.”

Clearly, more research will have to be conducted in order to confirm just how at-risk Martian explorers will be, and what can be done to protect them from cosmic rays (mice aren’t humans, after all). But to add one last bummer layer of news, Mars has a super thin atmosphere—less than one percent of Earth’s—so it will expose people to even more radiation once they land. Hopefully, this all gets sorted out soon before the Martian colonies begin, because goddamn would that be disastrous.

[Scientific Reports]