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what is the big red dot on jupiter
The Great Red Spot is a giant, spinning storm in Jupiter's atmosphere. It is like a hurricane on Earth, but it is much larger.
How big is the Great Red Spot in Jupiter
Jupiter's Great Red Spot is more than twice the size of Earth.
What is known about the Great Red Spot in Jupiter
The Great Red Spot a persistent high-pressure region in the atmosphere of Jupiter, produces an anticyclonic storm, the largest in the Solar System, 22 degrees south of Jupiter's equator.

Question: How long have scientists known of the spot
Self-contained rewrite: How long have scientists known of the Great Red Spot in Jupiter