Earlier this year, planetary scientist Amy Simon reported that the Great Red Spot extends 14,750 kilometers (9,165 miles) longitude and 10,500 kilometers (6,525 miles) latitude. However, recent measurements from Damian Peach cast doubt on these numbers, showing a significant reduction in size.
Using the WinJUPOS program to analyze high-resolution imagery, Peach determined that the Great Red Spot’s diameter on November 6, 2023, was 12,500 kilometers (approximately 7,770 miles). If verified, this measurement would be the lowest ever recorded by GRS and would surpass the GRS record. The previous record was 41,000 kilometers (25,500 miles) in the late 1800s.