Hank revisits his passion for exploring the Red Planet, breaking down the two biggest challenges of sending humans to Mars: radiation and propulsion. He explains the science behind the obstacles future Mars-bound astronauts will face, as well as they technology they'll have to use to surmount them. Onward! Like SciShow? Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids? Check out our awesome products over at DFTBA Records: dftba.com/artist/52/SciShow -- Looking for SciShow elsewhere on the internet? Facebook: www.facebook.com/scishow Twitter: www.twitter.com/scishow Tumblr: scishow.tumblr.com Sources for this episode: www.space.com/20499-dark-matter-space-station-ams.html www.space.com/20490-dark-matter-discovery-space-experiment.html www.nasaspaceflight.com/2011/12/year-in-review-p3-iss-new-discoveries-living-space/ www.americaspace.com/?p=33895 www.tested.com/science/space/456617-science-experiments-international-space-station/ www.cnn.com/2013/04/04/world/europe/space-dark-matter www.nasa.gov/mission_pages/station/news/1year_crew_feature.html#.Ugf57xafoUU www.nasa.gov/mission_pages/station/research/pfms.html www.bbc.co.uk/news/science-environment-22016504