Which planet had a Great Dark Spot that disappeared by 1994?

• A. Neptune
• B. Uranus
• C. Jupiter
• D. Saturn

Answer: (A)

The key idea here is planetary atmospheric storms and how long they last. On Neptune, scientists observed a giant dark storm known as the Great Dark Spot around the time of the Voyager 2 flyby in 1989. Neptune’s atmosphere is incredibly dynamic, with winds that are extremely fast and cloud patterns that shift rapidly. By 1994, that particular dark spot had faded away and was no longer visible in images, showing that some of Neptune’s storms are short‑lived compared to storms on other giants.

That contrast helps explain why Neptune is the correct answer: the Great Dark Spot disappearing by 1994 is a hallmark of Neptune’s variable weather. Jupiter’s storms, for example, like the Great Red Spot, have persisted for centuries, and while Uranus and Saturn have their own storms, the notable disappearing Great Dark Spot by 1994 specifically points to Neptune.