You'd burn up; you'd become atomized and part of Jupiter's atmosphere.

The Galileo probe that was dropped into Jupiter's atmosphere had a titanium hull. As I understand it, titanium melts at 3,100 degrees Fahrenheit. It most likely was vaporized. So, if this happened to titanium, human flesh wouldn't stand a chance.

Besides-even if you could survive that heat, there is nothing to splash down into. Jupiter is essentially a giant ball of liquid hydrogen, with a rocky core. Imagine a world-wide ocean, with no island. Also, there's a chance that there is no surface-the atmosphere just gets hotter and denser, gradually changing into liquid hydrogen. The air pressure at the transition point would be thousands of atmospheres.

Humans won't be able to explore this area directly for centuries, or perhaps for a millenium or two.

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