Using the James Webb Space Telescope (JWST), astronomers have discovered previously unknown structures and activities in Jupiter’s atmosphere above the Great Red Spot. These strange phenomena appear to be caused by strong atmospheric gravitational waves.
The Great Red Spot is the largest storm in the solar system, twice the size of Earth, and according to NASA, it has been raging for at least 300 years. The Great Red Spot’s winds rage at about 430 to 680 kilometers per hour, up to 3.5 times faster than a tornado here on Earth.
But despite the storm’s age, size, and power, scientists had previously assumed that Jupiter’s atmosphere above the Great Red Spot wasn’t all that interesting. However, these new observations from JWST’s Near InfraRed Spectrograph (NIRSpec) instrument, which observed the massive scarlet storm in July 2022, show that assumption couldn’t have been more wrong.
Related: Is Jupiter’s Great Red Spot an imposter? The giant storm may not be the original one discovered 350 years ago
“We thought – perhaps naively – that this region would be really boring,” said team leader Henrik Melin of the University of Leicester in a statement. “In fact, it is just as interesting as the Northern Lights, if not more so. Jupiter never ceases to amaze.”
What secrets does the Great Red Spot hide?
Jupiter’s upper atmosphere is the point where the planet’s lower atmosphere meets its magnetic field, resulting in bright northern and southern lights, which are powered by bombardment of charged particles from the Sun and by volcanic fountains erupting from Jupiter’s moon Io, the most active volcanic body in the Solar System.
Jupiter may be one of the brightest objects in the night sky above Earth, and is easy to see on a clear day. However, aside from its northern and southern lights, the atmosphere of the solar system’s largest planet is dimly lit, making it difficult for ground-based telescopes to see details through Earth’s atmosphere.
From its position a million miles from Earth, our planet’s atmosphere poses no obstacle for this $10 billion space telescope. In addition, JWST’s sensitivity in the infrared spectrum allows it to see the gas giant’s atmosphere in great detail, including the region above the Great Red Spot.
To find out if this region is a bit dim, Melin and his colleagues targeted it with NIRSpec, the main instrument on JWST. They discovered a variety of complex structures in JWST’s field of view, including dark arcs and bright spots.
Although incoming sunlight accounts for most of the light visible from Jupiter’s atmosphere, the team believes there must be another factor responsible for changes in the shape and structure of Jupiter’s upper atmosphere.
“One way this structure can be altered is through gravitational waves – similar to waves breaking on a beach and creating ripples in the sand,” explained Melin. “These waves originate deep in the turbulent lower atmosphere around the Great Red Spot and can travel upwards, altering the structure and emissions of the upper atmosphere.”
These gravity waves differ greatly from Gravity Gravitational waves, the latter are tiny ripples in space and time that Albert Einstein predicted in his general theory of relativity in 1915. Gravitational waves propagate through an atmosphere, as opposed to the fabric of space-time as gravitational waves. Waves do that.
These atmospheric gravity waves can also be observed occasionally on Earth, although these Earth-bound waves are much less intense and powerful than the same phenomenon that occurs over Jupiter.
Related: Gravitational waves vs. gravity waves: know the difference!
The team now hopes to use JWST to further pursue the discovery of these newly discovered features of the Great Red Spot and the complex wave patterns underlying them. This future investigation could shed light on how the waves flow through the gas giant’s upper atmosphere and how this causes the motion of the observed structures.
The findings are expected to contribute to a better understanding of the energy distribution on Jupiter and could benefit the Jupiter Icy Moons Explorer (JUICE) mission of the European Space Agency (ESA).
JUICE launched on April 14, 2023, and will reach Jupiter and its moons in 2031, conducting detailed observations of Jupiter and its three large ocean moons, Ganymede, Callisto, and Europa.
The team’s results were published in the journal Nature Astronomy.