Lifeboat Foundation

There are certainly a whole host of technological hurdles to overcome before humans successfully travel to Mars, or beyond, but research is also pointing to a growing assortment of fundamental health challenges that astronauts may face from long stretches of time in space. A recent NASA-funded study has found dormant viruses can reactivate in the human body during spaceflight, presenting yet another physiological problem for scientists to solve before we journey out into deep space.