"There are challenges to pioneering Mars, but we know they are solvable. We are developing the capabilities necessary to get there, land there, and live there," the NASA report said, noting the plan relies on an "evolutionary, resilient framework."
With a crewed round-trip voyage lasting more than 1,000 days, NASA has outlined its plans for the health and safety of astronauts, along with the logistics for landing, living and working on Mars.
"These technological and operational challenges fall into three categories: transportation, sending humans and cargo through space efficiently, safely, and reliably; working in space, enabling productive operations for crew and robotic systems; and staying healthy, developing habitation systems that provide safe, healthy, and sustainable human exploration," the report said.
NASA's testing will include the Orion space capsule, which during a return to Earth would need to withstand scorching temperatures. The SLS heavy lift rocket, which will help send Orion beyond low-Earth orbit, will also be put to the test in the coming years.
Asteroid Redirect Mission
NASA wants to relocate a piece of an asteroid and tow it into orbit around the moon as part of a test of new technologies that could be used on a manned mission to Mars. During the five-year Asteroid Redirect Mission, NASA will pluck a rock from an asteroid and haul it into orbit around Earth's moon.
In 2025, the space agency said it would then send two astronauts inside the Orion space capsule to explore the mini-asteroid, gaining more insight into robotic grabbing technologies, soft landings and allow astronauts to test suits that could be used for a deep space mission.
Landing on Mars
NASA calls entry, descent and landing one of its "biggest challenges" in planning the mission to Mars.
A braking system called "supersonic retropropulsion," which operates at speeds faster than the speed of sound may be needed in order to provide astronauts with a safe and precise descent onto the surface of Mars, the report said.
Well-Being of Astronauts
Going to Mars is of course a risk, since crewed missions won't be able to quickly return to Earth if a system fails.
"As crewed missions extend farther from Earth for longer periods, the habitation systems must become more reliable for safe, healthy, and sustainable human exploration," the report said.
The challenges NASA will have to solve include how to send crews with enough food, clothing and other supplies to make sure they're covered during a deep space mission. Mitigating potential health issues will also be another task NASA will have to tackle in the next two decades.
"Outside the Earth’s magnetic field, crew and electronics are exposed to high-energy particles, including infrequent, but potentially deadly, solar particle events and constant exposure to galactic cosmic rays. These high-energy particles can reduce immune response, increase cancer risk, and interfere with electronics," the report said.
NASA hasn't yet put a price tag on the plan, however, the report notes near-term projects can be funded with existing budgets, while long-term efforts can be funded by future "budgets commensurate with economic growth."