Jupiter's Great Red Spot Oscillates on 90-Day Cycle as 14,000-Km Storm Keeps Shrinking
Updated
Updated · spacedaily.com · Jun 5
Jupiter's Great Red Spot Oscillates on 90-Day Cycle as 14,000-Km Storm Keeps Shrinking
1 articles · Updated · spacedaily.com · Jun 5
Summary
Hubble's 2024 monitoring found Jupiter's Great Red Spot expanding and contracting in size and brightness over a roughly 90-day cycle, adding a short-term wobble to the famous storm's long decline.
14,000 kilometers across in recent measurements, the anticyclone is now only slightly wider than Earth, down from about 39,000 kilometers in 1879 and roughly 23,000 kilometers when Voyager passed in 1979.
NASA's annual Hubble tracking under the Outer Planet Atmospheres Legacy program has recorded the smallest size yet in that long record, while showing the storm has become more circular as it shrinks.
1831 is the firm continuous observation date, making the storm about 190 years old; a 2024 study argued it likely did not persist from Cassini's 1665 'Permanent Spot,' undercutting the often-cited 350-year age.
Why the storm keeps contracting is still unsettled: it feeds on Jupiter's atmosphere and smaller storms, but researchers do not know whether it will stabilize at a smaller size or eventually break apart.
If the Great Red Spot vanishes, could another superstorm of its scale ever form on Jupiter again?
Is Jupiter's shrinking storm dying, or is it evolving into a faster, more powerful vortex?
Jupiter’s Great Red Spot in Flux: Discovery of a 90-Day Rhythm and Accelerating Contraction
Overview
Between December 2023 and March 2024, Jupiter’s Great Red Spot surprised scientists by showing a new 90-day oscillation in its structure and movement. Using 90 days of continuous Hubble Space Telescope observations, researchers discovered that the storm wobbles and fluctuates in size with a rhythmic motion. This breakthrough was only possible thanks to dedicated, extended monitoring, which revealed subtle changes that had gone unnoticed before. The discovery challenges previous ideas about the storm’s stability and suggests there are complex internal dynamics at play, opening new questions about how this giant storm really works.