Jupiter's Great Red Spot

Abstract

THE great red spot of Jupiter has puzzled astronomers since its discovery in 1857 (or since 1664 if it is identical with the feature seen by Robert Hooke). It is generally conceded to-day that Jupiter is approximately 80 per cent hydrogen by weight^1–3, and the best modern evidence does not conflict with the assumption that hydrogen predominates in the atmosphere of Jupiter to the same extent as in the planet's bulk⁴. It has proved difficult to conceive of an ‘object’ able to ‘float’ in a surfaceless ocean⁵ of supercritical hydrogen gas. Therefore the suggestion of Hide⁶ that the red spot might not be a flotation phenomenon at all but rather a ‘Taylor column’ was an intriguing alternative. Unfortunately, it has not been possible as yet to prove hydrodynamically that a Taylor column can be realized in Jupiter's atmosphere; for one does not know enough about the hydrodynamic conditions of the atmosphere (we shall return to this point later). Moreover, certain observed phenomena appear to indicate that the rather restrictive requirements for the existence of a Taylor column are not met by the red spot. Without here going into these arguments, we merely wish to propose a novel and alternative explanation based on a theoretical prediction of J. D. van der Waals⁷ which has been verified in some detail by Krichevsky and Ziclis⁸, Kennedy and Takenouchi⁹ and others.