A massive red high-pressure storm that is Jupiter’s mysterious red storm which has lasted for hundreds of years, is now slowly changing its shape, size and colour. Astronomer Donna Pierce from Mississippi State University explains why this has been happening.
The red storm:
The Red Storm/ Spot is a high-pressure region in the atmosphere of Jupiter, producing an anticyclone-like storm. Being the largest in the Solar System, almost 22 degrees south of the planet’s equator, it has been continuously observed since 1830.
The Great Red Spot, a storm sized way larger than the Earth and compelling enough to tear apart smaller storms that get drawn into it, is one of the most substantial features in Jupiter’s atmosphere and the entire solar system.
Many questions about the Great Red Spot still remain unanswered, including exactly when and how was it formed, what gives it its striking bright red colour and why it has persisted for so much longer than other storms that have been observed in the atmosphere of Jupiter and the solar system.
Unlike Jupiter, planet Earth also has land masses that cause major storms to lose energy due to friction with a solid surface. Without this feature, Jupiter’s storms are evidently more long-lasting. The Great Red Spot is however long-lived, even by Jupiter standards. Researchers don’t quite understand the reason behind this, but we do know that Jupiter’s storms that are located in cloud bands with the same direction of rotation tend to be longer lasting.
Bands and Zones:
These colorful bands, called as belts (dark bands) and zones (light bands), run parallel to Jupiter’s equator. Researchers aren’t quite sure what is the main cause of the change in colour of the bands and zones, but differences in their chemical composition, temperature and transparency and quality of the atmosphere have all been suggested as contributing factors. These bands are also counter-rotating, meaning that they move in opposite directions with respect to their neighbor’s. The boundaries between the bands and zones are being marked by strong winds called zonal jets.
Similar to the Great Red Spot, these bands have undergone a slight change in latitude over time during which they have been observed. Researchers don’t entirely understand the banded structure of the equator, but we certainly do possess evidence suggesting that the light coloured zones are regions of rising hot material, and the dark belts are regions of heavy harmful material sinking into the atmosphere.
The Great Red Spot of Jupiter is changing dramatically and hence there is a change in its size, shape, and colour. In-Depth research and analysis of historical and recently obtained data on the Great Red Spot has shown that it is shrinking and becoming both rounder and taller, and its colour has also varied over time. What is driving these changes, and what do they mean for the future of the Great Red Spot and what will come out of it? Researchers cannot come to a valid conclusion yet.
However, NASA’s Juno spacecraft, currently orbiting Jupiter, is gathering more data on the cloud bands and the Great Red Spot.