by Kim Pederson…….

The concept of scale–the proportion of one thing compared to another–is a tricky thing. Take, for example, our solar system’s largest planet, Jupiter. If you put a solo NASA picture of Jupiter along side one of the Earth, your eyes would tell you that these two worlds appear to be about the same size. And then you, or me to be exact, would engage in a little research and the ridiculousness of that interpretation would become readily apparent, as the image below illustrates. Jupiter’s mass (or weight) is two and a half times that of the rest of the planets in our solar system combined. (To boggle your mind, okay my mind, farther, ginormous as it is, Jupiter’s mass is only one thousandth of our sun’s mass.) The famous Great Red Spot on Jupiter, a raging storm that has been going on for a least hundreds of years, is large enough swallow two or three Earth’s whole.

But what caught my eye recently about Jupiter was not its size or the eerie beauty of the colored bands that swirl around it, but something new to me: it’s aurora.

Jupiter’s aurora is much like our aurora borealis and aurora australis except, you guessed it, bigger. Much much bigger. As a reminder, my good friend Merriam-Webster notes that an aurora is “a luminous phenomenon that consists of streamers or arches of light appearing in the upper atmosphere of a planet’s polar regions and is caused by the emission of light from atoms excited by electrons accelerated along the planet’s magnetic field lines.”

The earth’s auroras are caused by charged particles from the sun (the solar wind) hitting our atmosphere and our magnetic field, which is strongest around the poles. Jupiter’s aurora, scientists think, is caused by the “massive gas giant’s own magnetic properties interacting with its upper atmosphere and exciting the gases that exist there, causing them to glow.” What’s even cooler about the aurora, according to the How It Works website, is that

you can also see the magnetic footprints of three of Jupiter’s four largest moons within the Jovian auroral blue glow. Io, Ganymede and Europa’s own auroras show up as three blobs of light and the electric currents generated by these three satellites move along the magnetic field of Jupiter while bouncing in and out of the atmosphere.

You can spot this magical effect–the bright blue dots in the aurora–in the photo above.

Besides the stunning visual nature of Jupiter’s glowing skullcap, there’s also something else very tantalizing about it: the energy. Or so I thought. The aurora produces about one million megawatts (the Earth’s auroras one thousand megawatts). Foolishly, when I read this I immediately jumped to the conclusion that if we could just run a high-tension line to Jupiter, we would have all the clean power we needed for our planet. Foolishly because the world consumes over 12 terawatts. A terawatt is one trillion watts. A megawatt is one million watts. So if I do my math correctly (and that’s a big IF), Jupiter, if we could tap into it, would provide less than 0.0001 percent of the energy we use.

So much for that idea, not that it was a sensible one to begin with. Back to the drawing board to solve our energy woes. Solar and wind power? Maybe. Nuclear? Only if we’re desperate. Geothermal? Not likely to end well on a massive scale (see The Core). No, I’m afraid the only way we can reliably reduce our power use and greenhouse gas emissions is for all of us to follow the Moor’s simple advice: “Put out the light and then put out the light” and then “put out the light and then put out the light” and then “put out the light and put out the light” and then…well, you get the idea.

*Approximate size comparison of Earth and the Great Red Spot, NASA, US-PD.
** Jupiter’s aurora, photo taken by Juno, NASA, US-PD.

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Visit Kim Pederson’s blog RatBlurt: Mostly Random Short-Attention-Span Musings.