Southern Lights Set the Sky Aflame

Is it just me, or has it been a slow week so far for space news post-AAS?

Admittedly, on the last night of the conference astronomers party like they mean it, as I discovered last year during the winter Austin meeting and had confirmed for me this year in Long Beach. [But that’s just a sample size of two—I need way more data, I think… ]

I was too busy busting a move to blog about it, but Eric Hand over at Nature found time for a quick post that sums up the atmosphere at this year’s gathering.

Word on the street is that the next winter meeting will descend on my hometown of Washington, D.C., and I can’t wait to see where the last-night shindig lands.

In the meanwhile, I guess folks are shaking off the effects of all those “Galileo 400″ cocktails and are gearing up for the global launch of the International Year of Astronomy in Paris this Thursday and Friday.

Perhaps riding the party vibe, my favorite spacey picture today features a psychedelic light show over the Amundsen-Scott South Pole Station in Antarctica.
—Photo courtesy Calee Allen, National Science Foundation

This is the aurora australis, a similar but less frequently seen effect to the Arctic’s northern lights.

Auroras regularly happen at both poles, thanks to solar particles speeding along the planet’s magnetic field lines. The energized particles collide with atoms in our atmosphere, releasing electrons in the form of colorful, ephemeral curtains.

(As much as I [heart] the written word, I find it’s easier to get this concept visually, so here’s a nifty video related to NASA’s THEMIS space physics mission.)

Most folks familiar with auroras tend to think of the borealis variety first, as more people live far enough north to see them.

The shimmering glow over Antarctica is largely enjoyed by penguins and polar researchers, so it’s a touch less famous. (As far as I can tell, the southern lights pretty much got the shaft in the His Dark Materials trilogy. What’s up with that Pullman?)

For what it’s worth, Earth isn’t the only player in the nighttime light-show department: The sun’s winds create a bubble that encompasses the whole solar system out to about about 8.7 billion miles (14 billion kilometers).

Add planetary magnetism and an atmosphere, and you’ve got auroras.
—Image courtesy NASA/Hubble/Z. Levay and J. Clarke

Pretty much every planet except Mercury and a few of the moons have shown some type of auroral goodness—on Jupiter, for example, the northern lights alone would cover the entire Earth.

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