Use reasoning to lead to the answer of the following question:
While in the neighborhood of Neptune, Voyager 2 discovered the "Great Dark Spot", which has since disappeared, according to observations by the Hubble Space Telescope. Originally thought to be a large cloud itself, the "Great Dark Spot" was later hypothesized to be a hole in the visible cloud deck of Neptune.\n\nAnswer this question based on the passage: what did the voyager 2 discover about neptune?

the `` Great Dark Spot ''
The relevant information is: While in the neighborhood of Neptune, Voyager 2 discovered the "Great Dark Spot", which has since disappeared, according to observations by the Hubble Space Telescope.

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The answer: the `` Great Dark Spot ''