لکه سرخ بزرگ The Great Red Spot

[1]- Anticyclone، طوفانی به گرد ناحیۀ پرفشار.
Wind speeds of up to 100 m s1 are common in the atmosphere and opposing circulation patterns caused, in part, by Jupiter’s rapid rotation rate cause storms and
turbulence in the atmosphere. The belts and zones are seen to vary in colour and
form from year to year, but the general pattern remains stable. The best known feature in the atmosphere is undoubtedly the Great Red Spot. It is a persistent anticyclonic storm, more than twice the diameter of the Earth, which has been observed
since at least 1831. It rotates in an anticlockwise direction with a rotation period
of about 6 days and is thought to be stable and so has become a permanent, or at
least a very long term feature of the Jovian atmosphere. It is not, however, fixed in
position, and though staying at latitude 22° south has moved around the planet
several times since it was fi rst observed. Similar, but smaller, features are common,
with white ovals of cool clouds in the upper atmosphere and warmer brown ovals
lower down. These smaller storms can sometimes merge to form larger features,
as happened in 2000 when three white ovals, first observed in 1938, combined
into one. In the following years its colour has reddened and it has been nicknamed
‘Red Spot Junior’.
"Introduction to astronomy and cosmology" Page 109