The Great Red Spot
The Great Red Spot has two possible discovery dates. One has The spot discovered by Robert Hooke in 1664. There is, however, an observational gap of about a hundred years between the 17th century observations of a great spot on Jupiter to observations in the 1800's of The Great Red Spot. This gap can be explained by the first spot breaking up and another forming or poor observational records. This uncertainty gives The Great Red Spot an age from 179 years to 353 years old.
