Jupiter’s Great Red Spot has been a source of fascination for astronomers for centuries. New observations from the James Webb Space Telescope (JWST) have revealed surprising details about the planet’s atmosphere above and around this iconic storm. A team of European astronomers led by Dr.
Henrik Melin used JWST’s NIRSpec instrument to conduct integral field spectroscopy of the Great Red Spot in July 2022. They expected the region to be relatively homogenous due to Jupiter receiving only 4% as much sunlight as Earth. However, they were surprised to find intricate wave patterns, including dark arcs, bright spots, and other structures.
Dr. Melin remarked, “We thought this region, perhaps naively, would be really boring. It is in fact just as interesting as the northern lights, if not more so.
New insights from Webb observations
Jupiter never ceases to surprise.”
The team suspects that gravity waves, similar to waves crashing on a beach, may be responsible for altering the shape and structure of Jupiter’s upper atmosphere. These waves are generated deep in the turbulent lower atmosphere around the Great Red Spot and can travel up in altitude, changing the structure and emissions of the upper atmosphere.
The researchers plan to conduct follow-up observations to investigate how these wave patterns move within Jupiter’s upper atmosphere and how they change over time. Their findings could also inform the European Space Agency’s JUICE mission, which will begin detailed observations of Jupiter in 2031. The Great Red Spot itself may not be as old as previously thought.
An analysis of historical records spanning nearly 360 years suggests that the current spot is distinct from the “Permanent Spot” observed by astronomer Giovanni Domenico Cassini and others from 1665 to 1713. Computer simulations indicate that a disruption in the wind between opposing jet streams may have kick-started the Great Red Spot. The spot has been shrinking since it was first observed in the 1800s and is currently about 1.1 times as wide as Earth.
Some experts believe it may eventually share the same fate as the Permanent Spot and disappear. Timothy Dowling, a planetary scientist at the University of Louisville, speculates, “There are some people who are alive right now — some younger kids — that may see the end of this one.”
As Jupiter continues to reveal its mysteries, astronomers eagerly await further insights into the planet’s complex atmosphere and the future of its iconic Great Red Spot.
