New research reveals that Jupiter's red “Permanent Spot” is actually two spots and neither of them are nearly as long-lasting as previously thought.
Knewz.com has discovered that the distant blemish, first observed by Italian astronomer Giovanni Domenico Cassini in the 1600s, is not the same red spot visible today.
A new paper published in the journal, Geophysical Research Letters, explains how a group of astronomers reviewed measurements of Jupiter’s former Permanent Spot and the current Great Red Spot to arrive at their conclusion.
They noticed that in the late 1800s, the Great Red Spot was at least twice the size of Cassini’s Permanent Spot.
The paper states that “numerical simulations rule out that the GRS[Great Red Spot] formed by the merging of vortices or by a superstorm, but most likely formed from a flow disturbance between the two opposed Jovian zonal jets [East to west winds observed in Jupiter’s atmosphere] north and south of it.”
Additionally, no records exist of either mark between 1713 and 1830 which to said scientists, indicates that during these 100 years, there was no red spot on Jupiter.
Records of a sighting in 1831 again suggest the occurrence of a different blemish which has been shrinking at a rate of 130 miles per year.
The study notes that if the spots were a single anomaly, they would have had to grow at a remarkable rate to achieve the size observed in 1831. However, there are no records of any spot during that period, let alone a growing one.
The paper’s lead author, Agustín Sánchez-Lavega, emphasized this, saying:
“From the measurements of sizes and movements, we deduced that it is highly unlikely that the current Great Red Spot was the ‘Permanent Spot’ observed by Cassini.”
“The ‘Permanent Spot’ probably disappeared sometime between the mid-18th and 19th centuries, in which case we can now say that the longevity of the Red Spot exceeds 190 years.”
The current red spot is an atmospheric vortex with the same diameter as Planet Earth. On the fringes of this storm, winds reach speeds up to 240 miles per hour.
The atmospheric chemical reactions produce a red hue which contrasts the surrounding clouds making it visible from Earth—even with the weakest of telescopes.
When Cassini first noted his permanent spot it was at the same latitude as the current Great Red Spot which led to a historic controversy in the field of astronomy.
Sánchez-Lavega is happy to put the argument to rest.
“It has been very motivating and inspiring to turn to the notes and drawings of Jupiter and its Permanent Spot made by the great astronomer Jean Dominique Cassini, and to his articles of the second half of the 17th century describing the phenomenon,” he said (via Science Daily).
“Others before us had explored these observations, and now we have quantified the results.”
