Day 6

NASA's dilemma: How to send humans to Mars without infecting the Martians

This week, U.S. President Barack Obama announced an ambitious goal to send humans to Mars by 2030. That makes Cassie Conley's task more urgent. She's NASA's Planetary Protection Officer and her job is to make sure humans don't screw up our first contact with alien life by contaminating the planet or ourselves. Or re-enacting the Andromeda Strain.
NASA's Curiosity Mars rover at the "Mojave" site, where its drill collected the mission's second taste of Mount Sharp. ((Photo by NASA/JPL-Caltech/MSSS via Getty Images))

This week, U.S. President Barack Obama pushed the Mars agenda closer to reality in an op-ed published by CNN. He says he wants NASA to send humans to the Red Planet, and he wants to do it by 2030, with the ultimate goal of colonizing Mars. How to get there and how to get home are important, unresolved issues. But as Dr. Cassie Conley tells Day 6 host Brent Bambury, it's equally important to find away to do it without contaminating the planet or ourselves.

Conley is NASA's Planetary Protection Officer, a position she's held since 2006. Her job is to make sure humans don't screw up our first contact with alien life by releasing a destructive strain of bacteria. (Think Andromeda Strain but real.)

"What we do depends on what target we're exploring," she says. "So for Mars, we recognize that there are habitats for Earth life so we have to prevent Earth life from getting to Mars."

Scrubbing the interplanetary equipment

For decades, NASA has sent orbiters, landers and rovers to collect data about Mars. Some measure radiation while others will study the availability of Martian resources, including oxygen. In every case, the machines have been cleaned and sterilized to protect against stowaway bacteria.

"On the Viking missions, the first landers we sent to Mars, we actually baked the whole spacecraft to kill off everything that could be on the surface," says Conley.

The deep clean is necessary because the point of these missions is to study the possibility of Mars life on Mars and not the Earth life that astronauts bring with them. But as NASA gets a better understanding of the red planet's environment, it has adjusted its procedures.

"For more recent missions, we've just cleaned them, kind of like cleaning your dishes. We scrub them with a washcloth," she says, adding that the microbes on the surface of these machines are about as clean as our hands. In other words, very clean but not totally sterile.

Turn the precaution up to 11

Conley says human contamination is an inevitable part of exploring another planet, but exploration won't take place at all unless they have enough information and have deemed it safe.

"We don't have that information right now so we're still being careful in order to get it," she says.

Conley points out that this is the same level of care that was used when NASA flew the Apollo missions to the surface of the moon.

"We had a lot of discussion about whether the lunar material could be hazardous and we had the quarantine program, so we've actually done this and we can learn a lot from it," she says.

NASA hasn't been to the moon since 1972 but still keeps the material gathered in a secure area. Conley says they will take equal or even greater care with materials from Mars.

"The first samples we bring back from Mars will be contained as if they are the most hazardous materials we know about — Ebola virus, biosafety level 4 containment. There is language in the outer space treaty that says we have to do this," says Conley.

Buzz Aldrin mans an experiment on the lunar surface during the first landing on the Moon on July 20, 1969. NASA learned a great deal about quarantine from the Apollo missions. (NASA/Newsmakers/Getty Images)

The role of private companies

The average Joe living today will probably never see the red, dusty surface of Mars but there are companies (SpaceX) and people (Elon Musk) who want to change that. For as little as $265,000, one could buy a ticket on Musk's still hypothetical jet to Mars.

Red Dragon is a planned unmanned SpaceX Dragon 2 capsule for low-cost Mars lander. The capsule will be a technology pathfinder for the much larger SpaceX Mars colonization architecture that was announced in September 2016. (SpaceX)

The idea of private companies making the same journey as NASA creates a problem — but as Conley points out, it is up to individual countries to regulate them.

"Within the U.S. it's an open question, but in the international context, the outer space treaty has a number of articles... If you combine them all together, it means that each country that signed the treaty has to be responsible for government and non-government ventures," she says.

In other words, countries should be putting laws and regulations in place now.


The long view

Ultimately, Conley says the real concern is the unknown.

"The presence of Earth organisms could have long-term consequences, because they could wake up after we've terraformed Mars and cause problems for colonists downstream," she says.

The concern is that organisms that are there now could be hazards in the future. Conley compares it to the threat posed by diseases and bacteria that that are currently lying dormant in permafrost here on Earth.

"Some of those diseases are coming back to life because as the permafrost thaws, the organisms are in a more hospitable place."