From what I understand, Jupiters Great Red Spot was first seen by Robert Hooke in 1664. From what I also understand, Telescopes weren’t around terribly long before this, either.
So, my question is this. Is it generally accepted that the Red Spot has been around for say, thousands if not millions of years and it just wasn’t observed until Hooke in 1664 because good enough telescopes didn’t exist before that time? Or, did it only actually form around 1664 and is hence only about 340 years old and its just a fluke that it happened to form at around the time that telescope technology was in its infancy?
This page says that it was first noticed in the 17th century. And since it has been around in full force since at least then, I think it would be safe to say that it was around for a while before then, too.
It’s impossible to know for sure how long it has been there, though.
I predict that, if the great red spot does shrink down into the background of all those other, smaller (yet still unimaginably vast) storms, one of the storms in the opposite hemisphere will increase in size and become the dominant visual feature of the planet.
At first glance, It doesn’t look like the great red spot has any influence across the equator of the planet, but I suspect its presence injects sufficient chaos to disrupt the formation of very large features in the other jet streams.
I can remember 40 years ago looking at Jupiter with my dad and how easy it was to see the red spot. With a much better scope, it is a challenge to spot these days. That’s how much it has changed.
I’ve seen Jupiter several times through a scope powerful enough to see the Spot, but just never happened to be looking at the right time: It was always on the far side.
That hasn’t been true since the early eighties. The width of the red spot is currently only 1.3 times the diameter of Earth and shrinking. It’s wider than it is tall, which means just one Earth would barely fit inside the spot.
