NASA scientists believe that no organism, human or otherwise, can live on Jupiter. The planet's high atmospheric pressure would crush humans, and almost any other organisms, while the inner temperatures would melt them. The planet is composed mainly of hydrogen and helium, making its conditions similar to those on the Sun.
In addition to pressure and temperature concerns, man-made spacecraft are at risk for damage by Jupiter's electrical field. The lack of any solid surface, aside from a theorized solid core, leads to severe weather conditions on the planet, such as the centuries-old storm known as the Great Red Spot. Although scientists consider Jupiter hostile to human life, some consider one of its moons, Europa, a possible host of life.