There are surprises in the game of life every day if we pay attention. Here’s one from the largest planet in our solar system: geometric clusters of cyclones on Jupiter.
Jupiter’s poles are blanketed by geometric clusters of cyclones and its atmosphere is deeper than scientists suspected. These are just some of the discoveries reported by four international research teams Wednesday, based on observations by NASA’s Juno spacecraft circling Jupiter.
Above: Cyclones circle, Jupiter’s North Pole, composite image from Juno data.
Above: Octogon of cyclones at one of Jupiter’s poles taken by the NASA Juno spacecraft.
The Juno spacecraft has the largest solar panels in the universe, as far as we know. It has 19,000 solar cells that extract energy from more wavelengths of light (colors) than ordinary cells used on earth.
The combined mass of the three panels is nearly 340 kg (750 lb). If the panels were optimized to operate at Earth, they would produce 12 to 14 kilowatts of power. Only about 486 W was generated when Juno arrived at Jupiter, projected to decline to near 420 W as radiation degrades the cells. The solar panels will remain in sunlight continuously from launch through the end of the mission, except for short periods during the operation of the main engine and eclipses by Jupiter.
Juno was launched August 5, 2011 and reached Jupiter orbit July 5, 2016, a 1,796 day journey (4.92 years). On March 7, 2018, these images from Juno were released on the photojournal JPL site:
Above: Jupiter’s southern exposure in infrared.
This computer-generated image shows the structure of the cyclonic pattern observed over Jupiter’s south pole. Like in the North, Jupiter’s south pole also contains a central cyclone, but it is surrounded by five cyclones with diameters ranging from 3,500 to 4,300 miles (5,600 to 7,000 kilometers) in diameter. Almost all the polar cyclones (at both poles), are so densely packed that their spiral arms come in contact with adjacent cyclones. However, as tightly spaced as the cyclones are, they have remained distinct, with individual morphologies over the seven months of observations detailed in the paper. The data used in generating this image was collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard the Juno spacecraft during the fourth Juno pass over Jupiter on Feb. 2, 2017.
Here is a new view on Jupiter’s North Pole
One group uncovered a constellation of nine cyclones over Jupiter’s north pole and six over the south pole. The wind speeds exceed Category 5 hurricane strength in places, reaching 220 mph.
The massive storms haven’t changed position much — or merged — since observations began.
Team leader Alberto Adriani of Italy’s National Institute for Astrophysics in Rome was surprised to find such complex structures. Scientists thought they’d find something similar to the six-sided cloud system spinning over Saturn’s north pole.
“We were wrong about it,” he said via email.
Instead, they found an octagon-shaped grouping over the north pole, with eight cyclones surrounding one in the middle, and a pentagon-shaped batch over the south pole. Each cyclone measures several thousand miles across.
Timeline: data collected by the craft on Feb. 2, 2017 was released to the public over a year later on March 7, 2018. One answer on Quora says that when the Juno craft is 870 million kilometers (541 million miles) from earth and that a signal takes a little over 48 minutes to reach us. Fact check: Seems right. It takes light 48.37 minutes to travel that distance and radio waves travel at the speed of light.
At the present time, a signal (a beep tone, for instance) from JUNO takes a little over 48 minutes to reach the DEEP SPACE NETWORK on Earth, the distance now being 870 million kilometers. This may slightly vary from day to day as all the related objects are in motion – Jupiter and Earth orbiting the Sun, and Juno orbiting Jupiter. When Jupiter is farthest from Earth it is almost a billion kilometers away. … The transponder on Juno uses 7153 MHz to receive and 8404 MHz to transmit. … Jupiter’s distance is 870 million kilometers now, about 6 times our distance from the Sun.
What causes the patterns in Jupiter is not well understood.
… what happens near its poles and below its cloud tops has long been a bit of a mystery. Thanks to its unique orbit, NASA’s Juno mission has now revealed some of Jupiter’s best-kept secrets. The results, published in four papers in Nature, show that the planet has surprising “polygonal” shapes of cyclones at its poles – including a pentagon at the south pole – and that its banded structure persists to depths of 3,000 km.
From Earth and spacecraft in certain orbits, we can only see Jupiter’s equatorial regions well. In fact, this has been the case for all previous missions to the planet. … Juno has a unique, highly elliptical orbit, giving it the first good views over Jupiter’s poles.
Every 53 days since July 2016, it has swept as close as 4,100 km above Jupiter’s cloud tops, giving it excellent views of its aurora – a type of “northern lights” caused by electrical currents in the rapidly rotating magnetosphere (a magnetic field) interacting with the planet’s atmosphere – and the polar regions of the atmosphere in visible, infrared and ultraviolet light.
As well as studying the aurora and magnetosphere, Juno also helps scientists probe the gravitational field of Jupiter’s interior in exquisite detail by monitoring small tweaks to the spacecraft’s orbit – down to 3,000 km below the clouds.
Being the largest planet in the solar system, Jupiter boasts a radius more than 10 times Earth’s, at nearly 70,000 km. The counter-rotating winds in the zones and belts reach speeds of 100 metres per second. Its main composition is hydrogen and helium – leftovers from the dense cloud of gas and dust, known as the solar nebula, that formed our solar system 4.6 billion years ago.
Below the cloud tops, the gas pressure is thought to increase hugely. At just 3,000 km below the clouds, the pressure should reach 100,000 bar, which is the pressure needed to synthesise diamond on Earth.
Further towards the centre, the pressure and temperature increase even further, and the hydrogen starts behaving like a metal. Models show that even further in we would reach an icy and rocky core with a radius about 20 percent of Jupiter’s. The models aren’t that reliable though, and this is where Juno comes in.
Peculiar polar patterns
Scientists were hugely surprised the first time they saw the poles of another gas giant – Saturn.
Cassini confirmed the Voyager discovery of a peculiar, huge hexagon feature in Saturn’s atmosphere near the poles. This surrounds a polar hurricane with a diameter of 1,250 km.
At the larger Jupiter, scientists didn’t expect to see this pattern at all. Instead, theories suggested that the zones and belts at the centre would weaken towards the poles leading to chaotic turbulence, rather than structured patterns.
But thanks to Juno, scientists have now discovered a huge cyclone at each pole, about 4,000 km in diameter in the north and 5,600 km in the south. Remarkably, these are surrounded by eight similarly sized cyclones in the north, and five in the south. These cyclones seem remarkably stable over the time that Juno has imaged them in the visible and infrared. The eight northern cyclones form a “ditetragon” shape (this is what you get if you connect two pyramids at the base) and the five southern cyclones form a pentagon shape (see lead image).
We don’t understand yet what causes them and why they are so persistent.