Question #39 – How many planets in our solar system have rings?
The answer is four! Saturn has the most impressive system of rings, but Jupiter, Uranus and Neptune all have ring systems.
Galileo first viewed Saturn through his telescope in 1610, but his telescope wasn't powerful enough to tell that it had a ring system. The rings were discovered in 1655 by Christiaan Huygens, who had a more powerful telescope. The ring system of Uranus was discovered in 1977 by astronomers using the Kuiper Airborne Observatory, a telescope that flys aboard a modified Boeing 747 plane. The Voyager satellites discovered the rings around Jupiter (1979 - Voyager 1) and Neptune (1989 - Voyager 2) on their journey out of our solar system.
More details can be found in Which Planets Have Rings? at Universe Today.