Tuesday, March 13, 2018

Jovian Skies

Juno is a spacecraft that was launched by NASA on August 5, 2011. After a journey of approximately 3 billion kilometers, Juno was inserted into an elliptical orbit around Jupiter on July 4, 2016 where it has been orbiting and carrying out its mission ever since. Its primary mission will last until July of 2018 and the spacecraft will eventually be intentionally crushed and burned up in the atmosphere of Jupiter. With its on-board instruments and cameras, Juno has been mapping the structure of the planet surface as well as making observations of the Jovian atmosphere,[1] at some points passing as close as about 4,000 kilometers above the atmosphere.

Juno’s cameras have given us the best resolution ever seen of Jupiter’s polar clouds. It has long been known that the atmosphere of Jupiter is constantly churned by massive cyclones. One fascinating observation made by Juno is that the polar storms order themselves in geometric shapes. The south pole of Jupiter has a storm that is encircled by 5 other cyclones creating a pentagon-like structure, while Juno has shown that the north polar region has eight cyclones situated in an octagon-like structure, surrounding a central polar storm.[2]

Many who have analyzed the data from Juno have been surprised to find geometrically regular shapes, but such shapes are not without precedence. The Cassini spacecraft confirmed the presence of a hexagon-shaped storm on Saturn’s north pole, which was first observed by the Voyager Mission flyby in 1981. We are more familiar with curves on earth, but the extreme nature of storms on other worlds can result in structures containing 5, 6, and 8 points. This will be of great interest to fluid dynamic engineers, and I am quite certain that such findings on Jupiter and Saturn will lead to scientific experiments that investigate the mechanisms involved in these regular geometric structures and the implications for planetary landings and other equally interesting consequences of atmospheric fluid motion.

Beyond our scientific fascination with such storms, the raw power and distinctive structures of these other-wordly storms may also inspire the poets, writers, and theologians to see and dream about what has been created.

Some went off to sea in ships,
    plying the trade routes of the world.
They, too, observed the Lord’s power in action,
    his impressive works on the deepest seas.
He spoke, and the winds rose,
    stirring up the waves.
Their ships were tossed to the heavens
    and plunged again to the depths;
    the sailors cringed in terror.
They reeled and staggered like drunkards
    and were at their wits’ end.
“Lord, help!” they cried in their trouble,
    and he saved them from their distress.
He calmed the storm to a whisper
    and stilled the waves.[3]

[1] Wikipedia, The Free Encyclopedia, s.v. "Juno (Spacecraft)," (accessed 2018-03-13), https://en.wikipedia.org/wiki/Juno_(spacecraft)
[2] Nature volume555, pages216–219 (08 March 2018); doi:10.1038/nature25491
[3] Psalm 107:23-29 New Living Translation

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