Two of the obstacles in getting humans to Mars, seems to be overcommed with the latest experiences in space: The breaking- and tochdown manouver and the physiological concerns

Launch decent and landing

NASA’s human Mars mission presents even more challenges of sending humans safely to a farther distance and to a more dangerous environment. Designing an aircraft that can safely enter and exit Mars’ unpredictable atmosphere is a big challenge.

“Each time we fly to Mars, we learn a little more and get a little smarter,” said Walter Engelund of NASA’s Langley Research Center. “One thing we have learned is that the Mars atmosphere is certainly a big variable. It is much more dynamic than our own Earth’s atmosphere.”

For missions that require entry and reentry into an atmosphere, the design of the spacecraft is typically guided by its EDL (entry, descent and landing) system. Engelund, along with several other NASA colleagues, published a review of the EDL systems currently being proposed for a future manned mission to Mars in a recent book titled “The Human Mission to Mars. Colonizing the Red Planet.” The book is a compilation of studies written by a team of more than 70 scientists, including four astronauts (two who walked on the Moon), offering a detailed guide of how to successfully accomplish a human mission to Mars. Engelund is the lead author of the EDL study.

Life sciences

The recent findings of water on Mars, to support life for an extended period of time, together with the experiences from the International Space Station makes makes it more comfortable to send humans to Mars

“A focused life and physical sciences program can make possible the achievements that bring the space community, policymakers, and the U.S. public to a realization that we are ready for the next significant phase of human space exploration,” said the committee co-chair, Elizabeth Cantwell, director of mission development, Lawrence Livermore National Laboratory, Livermore, Calif.

 For example, effective countermeasures are needed to offset the adverse effects of the space environment on the health and performance capabilities of astronauts on prolonged missions along with a deeper understanding of how gravity affects the human body.  This type of information will be essential to realize extended space voyages like Mars missions or a potential base on the moon.  In addition, astronauts on long missions would require the ability to collect or produce large amounts of water.  Research in the physical and life sciences that yields game-changing discoveries like regenerative power sources would also help make deep space travel feasible.

Sources: Kilder: NASA's astrobio site and National Academy of Science