(Roman Tkachenko/NASA/JPL-Caltech/SwRI/MSSS)

On July 11, NASA’s Juno satellite flew over Jupiter’s Great Red Spot — our solar system’s largest storm. The photos it sent back are incredible, in no small part thanks to citizen scientists who eagerly collected and processed the imagery so we can enjoy it.

Whilst you nerd out over the latest and greatest from Juno, here are some fun facts about the Great Red Spot itself:

  • Our first high-resolution look at the storm was from the Voyager 1 satellite in February 1979 (That’s the one that included 55 Earthling greetings just in case the satellite ran into some extraterrestrials.)
  • It’s actually a high-pressure storm. Winds in the Great Red Spot flow counterclockwise. The cloud tops in the storm are about five miles higher than the surrounding clouds.
  • If you were a parcel of air in the Great Red Spot, it would take you six Earth days to flow all the way around the storm.
  • The winds in the storm peak around 400 mph. In fact, everything on Jupiter is more intense than on Earth, not only because there’s no “ground” to create friction, but also because it only takes Jupiter 10 Earth hours to make a full rotation (add on top of that how huge this planet is and you start to realize how fast it’s spinning).
  • The spot has only been “well-studied” since 1879 but it may have been first seen in 1665 by Giovanni Cassini.
  • The storm is shrinking, longitudinally — or in other words, it’s getting skinnier. Based on the rate of shrinkage, it may become a circle (as opposed to its current oval shape) by 2040.
  • Scientists really don’t know why it’s red, but it’s probably because of a combination of chemicals in the atmosphere and radiation from the sun. Perhaps data from the Juno mission will finally put this question to bed!

NASA’s Juno satellite orbits in an oval pattern, with Jupiter on one side of the oval — as opposed to the center. So for most of the time the satellite is far away from the planet it was sent out to study. That orbit is necessary, though, to avoid Jupiter’s very strong radiation belts, which could obliterate the multibillion-dollar satellite.

The peculiar orbit means Juno only gets close enough to Jupiter to take measurements and snap photos every 53 days. And even then, it only takes two hours for the satellite to get from one pole to the other. It’s a lot of science in a very small amount of time. It has several more missions scheduled before its planned de-orbit in February 2018.

(User Derevyanko-19/NASA)


(NASA / SwRI / MSSS / Sean Korbitz)

(Roman Tkachenko/NASA/JPL-Caltech/SwRI/MSSS)