To prove that this wasn't just another vague statement by a government official, Bolden pointed out a number of projects NASA is currently engaged in which will be crucial in achieving its stated goal of getting humans to the vicinity of Mars by the mid-2030s. Bolden cited the one-year mission currently under way aboard the International Space Station to investigate the physiological and psychological effects of long-duration spaceflight on one astronaut and one cosmonaut. Bolden also cited the ongoing production and testing of the Orion space capsule and the Space Launch System, which will give NASA the capability of sending astronauts to pretty much anyplace in the inner solar system, including, the Moon, an asteroid, and Mars. NASA successfully completed the first unmanned test flight of Orion last December. The entire system is scheduled for a test launch in 2018.
Bolden also discussed NASA's current next goal, an asteroid capture mission, during which the agency plans to grab a boulder off of the surface of an asteroid and put it in orbit around the moon, where it can be visited and studied by astronauts by 2025. He made the case that, though it has been roundly criticized as a distraction, the asteroid capture mission is, in fact, a stepping stone on the path to getting humans to Mars. "We really are trying to demonstrate we can develop the technologies and the techniques," Bolden said, "to help commercial companies, entrepreneurs and others get to asteroids and mine them." Bolden also explained that part of this mission will be the field testing solar electric propulsion, a potentially crucial element of a Mars mission in terms of vastly driving down cost and launch weight, two elements that could potentially stall a Mars mission for years or even decades.
Other speakers included Scott Hubbard NASA's former "Mars czar", who reorganized the agency's robotic Mars exploration program after it suffered a series of failures in the 1990s. Hubbard is now working at Stanford University. He is also a member of the NASA Advisory Council tasked with evaluating the various methods for mounting a manned mission to Mars.
During his presentation, Hubbard made a number of important points, including the current surge in public interest in manned exploration of Mars, and perhaps the most crucial element in making a manned Mars mission a reality: "If you don't lay out this plan," Hubbard explained, "you will create uncertainty in partners and decision-makers." Hubbard also underscored the fact that NASA is not alone in pursuit of a manned Mars mission. There are a number of private organizations that have stated goals for getting humans to Mars. Hubbard cautioned that if NASA isn't intentional about getting a manned mission to Mars, it might miss the opportunity to be the first to arrive there.
Another speaker, former astronaut John Grunsfeld, countered detractors who say that a manned mission to Mars is just too expensive and that we can accomplish the same thing with robots for a fraction of the cost. First, he illustrated how much more efficient humans are at performing important scientific tasks as he estimated that the Curiosity rover's first mission which took the robot 90 days could have been accomplished by an astronaut in about 20 minutes. He went on to point out that if a robot or some other crucial piece of equipment breaks down and needs fixing, without humans on the ground, the mission is basically over.
(Sources: space.com, The Humans To Mars Summit)