NASA recently released some beautiful new photos of jupiter's Great Red Spot. On July 11, the juno spacecraft flew 5,600 miles above this large whirlpool, so close that we can view this 10,000-mile-wide vortex with an unprecedented perspective.
The images were quickly processed by genius citizen scientists, revealing spiraling red clouds within the site and the deep red central "nucleus" where the storm was calmest. We can see incredible details, including the shadows cast by the fluffy cloud network and swirls, and even the tiny waves at the edge of the Great Red Spot.
But while most people are very familiar with this Great Red Spot, there is much more that we do not understand. New observations from the Juno spacecraft may finally begin to solve these puzzles.
1. How long has it been?
The Great Red Spot is a long-standing swirling vortex. Even Victorian astronomers have provided detailed paintings and descriptions of the huge red stains on Jupiter's clouds. But its history may be even older than that. Observations by 17th-century astronomers Robert Hooke and Giovanni Cassini had similar characteristics, so the Great Red Spot may have been around for 4 centuries, or more. But what makes it possible to exist for so long, and why are there no other more similar eddies?
Clear diagram of the Great Erythema
2. Shrinking, but dying?
Because ground-based and space-based observations, including Hubble, have been tracking the size of the Great Red Spot, we know that the Great Red Spot has been shrinking for years. Voyager measured a width of 15,534 miles in 1979, but has now shrunk to 9,942 miles, just a little larger than Earth's diameter of 7,891 miles. But this atrophy is neither continuous nor uniform, with the Great Red Spot experiencing periods of rapid contraction from 2012 to 2014, but recently appears to have stabilized in this new, smaller-sized pattern. Who knows if we will witness the demise of the Great Red Spot, or if it will always be a permanent imprint of Jupiter's churning atmosphere.
3. What fuels it?
The Great Red Spot is like a ball of steel rolling between two prominent bands of Jupiter, and atmospheric jets are conveyor belts for smaller storm masses and swirls. But if these storms are unfortunate enough to encounter the Great Red Spot, they will be engulfed by it. Perhaps these smaller swirls provide the extra energy and angular momentum needed to sustain the rotation of the larger vortex, but we can't know for sure.
Mixtures of gases and clouds found within the Great Red Spot also indicate the presence of a strong high tide (known as upwelling) in the center, which may transfer heat upward to maintain the vortex. The new high-resolution images show that the center of the storm is dark red, and the delicate details in it will help us learn more about the dynamic properties of the red spot core.
4. How deep?
If you are somehow able to fly in a hot air balloon at the edge of a whirlpool storm, you will be blown around the whirlpool for 3.5 days. But the Great Red Spot isn't exactly the same as a hurricane: there's no ocean underneath to sustain its energy, and no one really knows exactly how deep it goes into the atmosphere. Is this just a feature in the upper clouds? Or deeply rooted in Jupiter's interior, digging out minerals from inside Jupiter? This may explain why it has remained stable for a long time. The new images, along with Juno's microwave and gravitational observations, may reveal for the first time how deep the Great Red Spot extends.
5. Why is it red?
Although after decades of planetary exploration, we still don't know how Jupiter's cloud top interacts to form the red spots we see. In this regard, the Great Red Spot is not always red: it sometimes fades to orange, or appears orange-red or rusty brown. These colors may be related to chemical bonds in materials excavated by solar decomposition storms upwelling. These chemicals may contain sulfides, phosphides, and hydrocarbons, all of which may form red. Juno's instruments, along with these spectacular new photographs, may help solve the puzzle.
6. Is the core warm?
At the top of the clouds, the Great Red Spot is cold because the airflow within the vortex rises, expands, and cools. This cooling causes the airflow to condense into ice, creating a thick cloud mass above the storm. But thermal infrared images show that the Great Red Spot has a warm core. This warm area, which coincides with the crimson clouds in the new image, may be a stationary zone for the storm. Will the vortex core tell us what the depths of the storm look like? If so, what is the temperature below the clouds? Similarly, Juno's microwave observations may reveal the answer.