Question 961

Another astronomy question:

X is a persistent anticyclonic storm, 22° south of Y's equator, which has lasted for at least 180 years and possibly as long as 345 years or more.The X rotates counterclockwise, with a period of about six Earth days or 14 equivalent Y days. Its dimensions are 24–40,000 km west–to–east and 12–14,000 km south–to–north. It is large enough to contain two or three planets the size of Earth. At the start of 2004, X had approximately half the longitudinal extent it had a century ago, when it was 40,000 km in diameter. At the present rate of reduction it could potentially become circular by 2040, although this is unlikely because of the distortion effect of the neighboring jet streams.

Infrared ata have long indicated that X is colder (and thus, higher in altitude) than most of the other such phenomena on Y. Furthermore, careful tracking of atmospheric features revealed the X's counterclockwise circulation as far back as 1966.

Identify X and Y.
Answer: X: The Great Red Spot Y: Jupiter