Hubble Spots Changes in Jupiter's Great Storm
A giant storm on Jupiter has been continuing for at least 150 years, and scientists have discovered that it appears to be changing more regularly than had been thought.
The Great Red Spot (GRS) is a huge storm that rotates around an area of high pressure in Jupiter's atmosphere.
The storm is generally red in color, with winds that can reach nearly 700 kilometers per hour. It is around 16,000 kilometers wide, making it big enough that the whole Earth could fit inside it.
Scientists have been continuously watching the GRS since 1878. But new images of the storm, published as part of a study in The Planetary Science Journal, show that its size and shape seem to be regularly changing — or "oscillating."
Taken by the Hubble Space Telescope over 90 days between December 2023 and March 2024, the new images of the GRS show that the storm's oval shape actually gets a little larger and then smaller again over time.
Amy Simon, a planetary scientist at NASA and lead author of the study, said these oscillations had not been seen before. She said there is no known explanation for why they happen, and called the discovery "very unexpected."
It's also still not known why the GRS is red, or why it has continued so long. A spot has been seen on Jupiter since the first European scientists looked at it through telescopes in the 1600s, but it's not known if this was the same storm as the one we see today.
Simon said learning more about the GRS could help scientists understand Earth's weather system better.
Jupiter is a gas planet made up of mostly hydrogen and helium, and it may not even have a solid core. Despite these big differences, Jupiter's weather works under the same physics as Earth, Simon says — just millions of kilometers farther from the sun.
