system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Could a spacecraft fly through a gas planet like Saturn?

It's all gas, right? Even if the spacecraft could not "escape" the gravity and come out the other side, could it "fly" all the way to the core? Would it hit something in the middle?
gpt
Yes, it is gas, but it not all gases are equal. For example, the density of Earth's atmosphere (at sea level and 15 degrees C) is about 0.001225 g/cm^3 . By contrast, the average density of Saturn is 0.69 g/cm^3 . So while Saturn has the distinction of being the only planet less dense than water (on average) it is still about 6,000 times more dense than our atmosphere. The upper atmosphere of Saturn has pressures ranging up to almost double that of our own Atmosphere and increases to about 5 times our atmospheric pressure as you go down.

To make matters worse, there are wind speeds. Saturn's atmosphere has the second fastest wind speeds in the solar system upwards of 500 m/s.

So it's not likely that any man-made craft is going to survive entry into Saturn's atmosphere; it'll get ripped to shreds from the winds.

Assuming you can survive, it's up for debate as to wether it is simply increasingly dense gas all the way down or if there is a icy core from a result of all the pressure.