The planet is mostly swirling gases and liquids. While a spacecraft would have nowhere to land on Jupiter, it wouldn't be able to fly through unscathed either. The extreme pressures and temperatures deep inside the planet crush, melt, and vaporize spacecraft trying to fly into the planet.

Can you fly through gas giants?

No landing has been attempted on any of the gaseous Jovian planets primarily because there is no surface on which to land. Sending a spacecraft flying through the atmosphere of one is also impractical for several reasons.

What would happen if you flew into Jupiter?

Jupiter's deep atmosphere absorbs radio waves, so you'll be shut off from the outside world— unable to communicate. Once you've reached 2,500 miles down, the temperature is 6,100 ºF. That's hot enough to melt tungsten, the metal with the highest melting point in the Universe.