SafekipediaAtmosphere of Jupiter
Adapted from Wikipedia · Discoverer experience
The atmosphere of Jupiter is the largest planetary atmosphere in the Solar System. It is mostly made of molecular hydrogen and helium in roughly solar proportions. Other chemical compounds like methane, ammonia, hydrogen sulfide, and water are present only in small amounts. Jupiter’s atmosphere changes gradually from gas to liquid as you go deeper, without a clear lower boundary.
Jupiter’s atmosphere has several layers, including the troposphere, stratosphere, thermosphere, and exosphere. The troposphere contains clouds and hazes made of ammonia, ammonium hydrosulfide, and water. These clouds form bands around the planet, with dark areas called belts and lighter areas called zones. Strong winds, known as jets, run along these bands, creating a spinning motion called atmospheric super-rotation.
Jupiter’s atmosphere is full of active weather, including huge storms and spinning spots called vortices. The most famous is the Great Red Spot, a massive storm large enough to swallow several Earths. These storms sometimes produce very powerful lightning, much stronger than lightning on Earth, as warm air rises and creates tall, bright clouds.
Vertical structure
Jupiter's atmosphere has four layers: the troposphere, stratosphere, thermosphere, and exosphere. Unlike Earth's atmosphere, Jupiter does not have a mesosphere. The troposphere, the lowest layer, blends smoothly into Jupiter's fluid interior because there is no solid surface. The temperature in the troposphere gets colder as you go higher until it reaches its coldest point at the tropopause, which is about 50 km above the visible clouds.
In the stratosphere, temperatures begin to rise. The thermosphere continues this trend, with temperatures reaching up to 1000 K. Jupiter's clouds are made of different materials depending on their height. The highest clouds are made of ammonia ice, while lower clouds may contain ammonium hydrosulfide or water. The thermosphere shows beautiful glowing lights called aurorae and can emit X-rays.
Chemical composition
The atmosphere of Jupiter is mostly made of molecular hydrogen and helium. These two gases make up almost the entire atmosphere. Small amounts of other compounds are also present, including methane, ammonia, hydrogen sulfide, and water. Water is believed to be deep within the atmosphere, but it is hard to measure directly.
Scientists have learned a lot about Jupiter's atmosphere by using spacecraft like the Galileo probe and telescopes. They found that Jupiter has a bit less helium than expected, possibly because some of it has settled into the planet's core. Other elements like carbon, nitrogen, sulfur, and oxygen are found in larger amounts than in the Sun.
| Element | Sun | Jupiter/Sun |
|---|---|---|
| He/H | 0.0975 | 0.807±0.02 |
| Ne/H | 1.23×10−4 | 0.10±0.01 |
| Ar/H | 3.62×10−6 | 2.5±0.5 |
| Kr/H | 1.61×10−9 | 2.7±0.5 |
| Xe/H | 1.68×10−10 | 2.6±0.5 |
| C/H | 3.62×10−4 | 2.9±0.5 |
| N/H | 1.12×10−4 | 3.6±0.5 (8 bar) 3.2±1.4 (9–12 bar) |
| O/H | 8.51×10−4 | 0.033±0.015 (12 bar) 0.19–0.58 (19 bar)[b] |
| P/H | 3.73×10−7 | 0.82 |
| S/H | 1.62×10−5 | 2.5±0.15 |
Zones, belts and jets
The surface of Jupiter shows bands running parallel to the equator. These bands are of two types: lighter-colored zones and darker belts. The wide Equatorial Zone stretches from about 7° South to 7° North. Above and below this, we find the North and South Equatorial belts, and further out, the North and South Tropical zones. These bands continue until around 50° latitude near the poles.
Zones appear lighter because they have more ammonia, creating denser clouds higher up. Belts are darker with thinner clouds at lower heights. Between these bands flow fast winds called jets. Eastward jets occur where zones meet belts, and westward jets where belts meet zones. These jets can speed up to over 100 meters per second and dive deep into Jupiter’s atmosphere, running alongside the planet’s rotation.
The pattern of zones and belts may come from rising air in zones and sinking air in belts, similar to weather patterns on Earth. While the positions and speeds of these bands and jets stay mostly the same, their colors and details can shift over time.
Dynamics
Jupiter's atmosphere moves very differently from Earth's because Jupiter has no solid surface—its interior is fluid all the way through. Scientists are still working on a full explanation for how its winds and weather patterns work. They study two main ideas: one suggests that the weather happens only in a thin outer layer, while the other suggests that the patterns we see on the surface come from deep currents inside the planet.
Both ideas have strengths and weaknesses. The thin-layer idea can explain some of Jupiter's narrow wind bands but struggles with others, like the strong eastward jet at the equator. The deep-current idea explains some features better but is still being tested. Scientists use both ideas to try to understand Jupiter's complex atmosphere.
Moist-convection and Y-shaped Structures on Jupiter's Equatorial Zone
Deep convection on Jupiter happens when water condenses under pressure, forming clouds of ammonia, hydrogen sulfide, and water. In deeper layers, water becomes the main cloud-forming substance. Strong storms may mix ammonia and water to create special structures called "mushballs" that carry ammonia deeper into the atmosphere.
Y-shaped structures on Jupiter's equator might form when large-scale heating creates a hybrid structure combining a stable dipolar shape with a fast-moving wave. This structure moves eastward before eventually separating into independent parts. Moist convection is needed to start this process.
Internal heat
Jupiter gives off more heat than it receives from the Sun. This extra heat comes from Jupiter's early formation and possibly from helium sinking into its core. This internal heat helps keep Jupiter's atmosphere evenly warm from the equator to the poles, with convection playing a key role in distributing the heat.
Main article: Internal heat
Discrete features
The atmosphere of Jupiter is home to many rotating structures called vortices. These can be divided into two types: cyclones and anticyclones. Cyclones rotate in the same direction as Jupiter, while anticyclones rotate in the opposite direction. On Jupiter, anticyclones are more common, especially the larger ones. These vortices can last from several days to hundreds of years, depending on their size.
One of the most famous features is the Great Red Spot, a large anticyclonic storm that has been observed for over 350 years. It is big enough to fit two or three Earths inside. Another notable storm is Oval BA, which formed in 2000 and turned red in 2006, earning the nickname "Red Spot Jr."
Storms on Jupiter are similar to thunderstorms on Earth. They appear as bright, clumpy clouds and are powered by lightning. These storms are short-lived, usually lasting only a few days, but can sometimes last several months. Jupiter also has cyclones near its poles, which have been studied by the Juno spacecraft. These cyclones form interesting patterns and help scientists understand Jupiter's atmosphere.
Observational history
Main article: Exploration of Jupiter
Early astronomers used telescopes to watch Jupiter's changing atmosphere, giving names to its different features like belts, zones, and spots. Later, space probes like Pioneer 10 and Pioneer 11 gave us closer looks, followed by detailed images from the Voyagers. Today, telescopes like the Hubble Space Telescope let scientists watch Jupiter's atmosphere over time.
The famous Great Red Spot was first seen in the 1600s and has been studied ever since. In 1979, Voyager 1 sent back the first close-up pictures. Scientists also watch other storm shapes, like white ovals, which change and move over many years.
Images
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