Jupiter’s Great Red Spot Reaches the Gas Giant
The Great Red Spot — the iconic, circling eye of Jupiter, an ongoing storm that engulfs the entire Earth — has many more surprises. Scientists studying the depths of the planet from afar have now found that the cosmic cyclone reaches about 300 miles into the atmosphere of the gas giant.
Utilized sensitive instruments aboard NASA Juno space probe, the first spacecraft to orbit Jupiter in two decades, astronomers used gravity and microwave measurements to reveal that the Great Red Spot is deeper and has a more complex structure than previously thought. They publish their findings on journal Science on Thursday.
“This is the first window we have in the depths of Jupiter,” said Scott Bolton, an astrophysicist at the Southwest Research Institute in San Antonio, the Juno mission’s lead investigator and author of one of the two papers. “If you look at the Great Red Spot on the side, it looks like pancakes, but we expected the pancakes to be thinner.”
The Juno is slightly larger than a school bus, and it’s a bit larger on the largest planet in our neighborhood, where the probe has been orbiting since 2016 at an altitude of more than 10,000 miles. But it packs a lot of cutting-edge technology into it, including the tools needed for the Gravity Science experiment. Since Jupiter does not have the same density throughout, its rolling content can be determined by small fluctuations in the planet’s gravitational pull. Juno is equipped with a radio transponder, which bounces signals on NASA’s Deep Space Network, a series of radio antennas on Earth that support various interplanetary space missions. If there is a small change in the frequency of the return signal, that means that the speed of the spacecraft has shifted — due to higher or lower gravity pulling within the particular part of Jupiter it is flying. It’s a similar concept to how NASA Grace satellites measure the depleted ground water below the surface of the Earth.
“The disturbances are very small: We’re talking 10 micrometers per second. It’s amazing that we have this accuracy with this instrument,” said Marzia Parisi, a Juno scientist at NASA’s Jet Propulsion Laboratory in Pasadena. , California, and author of another recent study, focusing on these gravity measurements.
Parisi and his colleagues found that most of the mass of the Great Red Spot is within 200 or 300 miles of Jupiter’s atmosphere. That’s not small. If such a storm develops on Earth, its length is greater than the distance between the earth and the altitude of International Space Station.
Astronomers often compare the activity of Jupiter’s atmosphere to Earth’s time. The Great Red Spot can be compared to the biggest hurricane or hurricane ever. (Technically, because the big storm rotates counterclockwise, scientists call it a anticyclone.) But the terrestrial weather is mediated by the ocean and land below, which can destroy the storm, while Jupiter is gas to the bottom. “I don’t think we’re going to have an eternal storm” on Earth, says Parisi. Astronomers believe that the Great Red Butik has existed for centuries.