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]

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[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

The Dance of the Planets

 (Photo credit: Universe Today)

I have continued to enjoy the movements of Venus, Jupiter, and Mars. This particular conjunction of planets has now inspired my imagination for several weeks. Each morning I look to the east around five or six am to see if it is clear enough to see this amazing display. The relative arrangement of the three planets and the bright star, Regulus, are slightly different each day and change from hour to hour. The rate at which each one rises in the morning is dependent not only on the spin of our earth but also the movement of the planets in their orbits relative to earth’s position in her orbit around the sun. I am intrigued each day to see where each planet appears relative to the others. I am always amazed by the slightly red hue of Mars as seen from earth. This red colour is thought to be caused by the scattering of red photons in the atmosphere of Mars. The soil of Mars contains much iron that turns to a rusty red colour due to oxidation and the dust of this red iron is kicked up into her atmosphere by surface winds.

I can see why the Psalmist was inspired to write poetry about his observations of the night sky. May we never lose our sense of awe about the planets and stars.

Psalm 8 (NLT)

For the choir director: A psalm of David, to be accompanied by a stringed instrument.

¹ O Lord, our Lord, your majestic name fills the earth!
    Your glory is higher than the heavens.
² You have taught children and infants
    to tell of your strength,
silencing your enemies
    and all who oppose you.

³ When I look at the night sky and see the work of your fingers—
    the moon and the stars you set in place—
⁴ what are mere mortals that you should think about them,
    human beings that you should care for them?
⁵ Yet you made them only a little lower than God
    and crowned them with glory and honor.
⁶ You gave them charge of everything you made,
    putting all things under their authority—
⁷ the flocks and the herds
    and all the wild animals,
⁸ the birds in the sky, the fish in the sea,
    and everything that swims the ocean currents.

⁹ O Lord, our Lord, your majestic name fills the earth!

(Photo credit: Universe Today)

Cassini and Hyperion

The Cassini spacecraft recently completed a close flyby of Hyperion, one of the moons of Saturn, and sent back some amazing pictures. Hyperion is certainly one of the more odd shaped moons in our solar system. Whereas people used to think Earth's moon was made of cheese, Hyperion truly looks like Swiss cheese. The surface and interior of the moon are filled with pores and tunnels giving it the appearance of a sponge. In fact, much of the planet is made of water ice with very little solid rock. There are so many holes in the moon that if you could find a pool of water large enough, say our own Atlantic Ocean, the moon would float with about half of its bulk sticking out of the water. Hyperion is known to have an erratic rotation. It wobbles on its own axis and its orbit about the planet is eccentric and highly influenced by its proximity to Titan, Saturn's largest moon.

The Cassini robotic spacecraft itself has had an amazingly successful mission in space. Originally launched in October of 1997, the spacecraft is now in its second mission extension which will see it perform active scientific observations through 2017. On its way to Saturn, Cassini flew past Venus and Jupiter, relaying information on each of those planets before achieving orbit around Saturn in July of 2004. In December of 2004, Cassini released the Huygens probe which successfully landed on the surface of Titan, sending back 350 pictures of this large moon. This latest flyby of Hyperion is the last for that moon. Now Cassini sets its sites on other moons in the Saturnian system. In 10 days Cassini will fly past Dione and send back images of that moon. Today, she is in position to get a good look at Enceladus and the outer rings of Saturn (see the image below).

We live in a time when it is possible to learn much from the exploration of our solar system. I am thankful for the scientists and technicians at NASA's Jet Propulsion Laboratory that use their imaginations to design and execute such amazing missions to the outer reaches of our solar system.

Works cited:
Cassini–Huygens in Wikipedia, http://en.wikipedia.org/wiki/Cassini%E2%80%93Huygens

Hyperion (moon) in Wikipedia, http://en.wikipedia.org/wiki/Hyperion_(moon)

NASA, Jet Propulsion Laboratory, Saturn, Cassini, http://saturn.jpl.nasa.gov/

Science News, "Cassini gets last look at Saturn’s spongy satellite Hyperion," 2015-06-04, https://www.sciencenews.org/blog/science-ticker/cassini-gets-last-look-saturn%E2%80%99s-spongy-satellite-hyperion?tgt=nr

You can click on these images for a larger view.