Can NASA put a human being on Mars? It's more likely than you think. The agency recently released its objectives for a 30-day crewed mission to the red planet, as well as elaborated on some of the many challenges humans might face in the course of their duties.
NASA's goals for this mission fall under four broad categories: science, operations, transportation and habitation, and Moon and Mars infrastructure. Each of these has multiple objectives, including:
The goals run the gamut from developing critical systems for future missions, to further studying the effects of long and short-term exposure to the lunar and Martian environment. NASA also hopes to be able to learn more about space weather phenomena, in order to better predict conditions for deep space missions.
One particularly interesting set of objectives relates to the crew, plants, and microbes. The astronauts will be provided with plants for nutrition and mental health purposes, as well as to see what the short- and long-term effects of life on the lunar surface might be. We know that plants don't grow very well in lunar soil, but this will give researchers the chance to see what permanent or temporary physiological changes arise across several generations of organisms.
NASA hasn't yet set any specific dates for this mission. They're still soliciting public feedback on their stated objectives until June 3rd. The feedback they receive will impact their goals going forward.
Right now, the plan is for a 30-day long mission for four people. Two will descend to the Martian surface to conduct research, similarly to the Apollo program, while two will stay onboard the ship.
NASA hopes to launch a crew to Mars by the late 2030s to the early 2040s. There's still a long way to go before they're anywhere near ready to so this—in addition to asking for and considering public feedback, there are a lot of obstacles standing in the way that need to be overcome if the mission is going to be a success.
The first problem with any manned space mission is the “manned” part. Humans evolved on Earth, and our bodies operate best in Earthlike conditions. Most science fiction that features long trips in space involves some kind of artificial gravity, but that hasn't been made a reality yet. Instead, astronauts will have to contend with deconditioning during the almost 250 day trip out. That means that, from a physical standpoint, they probably won't be strong enough to cope with moving around a lot in Martian gravity. While the planet only has about a third of the gravity of Earth, it's still much more than the microgravity of space. It's likely that the crew will have to live in and travel around the surface using pressurized vehicles until they've re-conditioned.
Another potential obstacle lies in equipping the crew. They're going to need a lot of supplies to get anywhere near meeting NASA's mission objectives—about 25 tons worth. This would have to be delivered and set up by a preliminary robotic mission, which has its own challenges.
A third lies in the ship itself. A journey this long requires a ship like a habitat, capable of sustaining human life for about 500 days round-trip. There's a lot to consider, like the ability to provide healthcare and mental stimulation, as well as mitigate the physical impact of long-term exposure to microgravity.
NASA isn't yet at the point where they can begin accepting contract bids just yet, and this mission to Mars is still very much in the planning stages. If the feedback they receive is favorable, and they're able to overcome the unique challenges posed by a mission of this distance and duration, then humankind may put a person on Mars within the next twenty years.
