Jupiter smells like something that looks like urine with a bacterial infection, that is, that stinks ammonia (more than Uranus or Neptune does). It's what NASA researchers suggest in Science and Geophysical Research Letters.
This data has been extracted thanks to the Juno mission.
Juno mission data
More data that has been extracted from the Juno mission on Jupiter is that cyclones and apocalyptic storms take place at their poles. Its gravitational field is also completely different from what was believed so far, the magnetic field is twice as strong as it had been calculated and the way in which the auroras are produced, is completely different from that of our planet.
At the moment the probe has only had a couple of approaches to the giant planet, so it is soon to draw conclusions. What scientists do say is that the structure of the planet is much more complex than previously thought.
It is hardly the second approach we have to Jupiter, we still have a lot to learn from this planet. Jupiter's data could even help researchers around the world understand how planets form in general.