Round trip to Mars would take about 21 months. Nine to get there, three to do some science and wait for a return launch window, then nine more months to get back. More details on that here...
https://image.gsfc.nasa.gov/poetry/venus/q2811.html
Probably need the skill sets of at least six people who are going to have to live together in a soup can the size of a railroad tank car for the better part of two years without killing each other or going totally mental.
Forget the technical challenges of a manned mission; the psychological challenge is far more daunting.
Bookmarks