Every now and again my work piles up and I can feel that edge of panic start to set in.
Then I saw a video and my brain let out a nice long sigh (brains are remarkable that way): Alberta Aurora – Prairie Light, a lovely time lapse that has better-than-usual resolution and color, taken as the April 23/24 solar storm swept over the Earth.
What you see in an aurora depends in part on the angle of the Earth’s magnetic field relative to the air; the geomagnetic field guides particles from the Sun’s outbursts into our atmosphere. If you are seeing this from far enough away, you get those sheets and ribbons, the interaction seen from the side. But at 1:50 into the video the perspective changes. The camera is underneath the point where the particles are streaming in, so you’re looking up, right into the barrel of the magnetic field. It’s a remarkable change in view that must be awesome to see in person.
I’ve never seen a full-on aurora, but some day I will. I hope it’s as pretty as this one was.
- The green fire of the aurora, seen from space
- January’s aurorae from way far north
- Faith and begaurora (because no one – not one person – sent me love over the AWESOME title I gave this post)
- The rocket, the laser, and the northern lights
The view from the International Space Station is always pretty cool, but when an astronaut points the camera at the Earth’s horizon and takes a series of short exposures, adding them together gives a view right out of Haight-Ashbury in the 1960s:
[Click to psilocybinate.]
Astronaut Don Petit took the pictures to make this composite. Basically, it’s a series of eighteen 30-second exposures added together so the motion of the ISS around the Earth makes the stars trail, the cities blur, and your mind expand, dude.
The brown and green glow over the horizon is the atmospheric aerosol layer; molecules that absorb sunlight during the day and release that energy at night. The red glow above that puzzles me; I’ve written about it before. It might be a reflection of lights from inside the space station, but I suspect it’s actually the aurora; it follows the curve of the Earth, and as you can see from the star trails the camera was pointed toward the poles — the direction you’re likely to see an aurora.
ou can see faint star trails above the bright ones too, with a different center of curvature — those probably are from an internal reflection. Either that or the camera got moved, but that seems unlikely! Several people pointed out to me that the fainter trails above the stars are from the solar panels. I should’ve realized that myself!
This picture is one of several posted to Flickr, including this one which looks like it’s from the last scene of "2001: A Space Odyssey". But they’re all worth looking at, if only for their alien beauty.
After all, the photographer was literally high when he took them!
Image credit: NASA
Because you simply cannot have enough incredibly beautiful photographs of aurorae in your life, here’s one taken near Tromso, Norway, on March 28, 2012 by photographer Helge Mortensen:
[Click to coronalmassejectenate, and you should.]
What a shot! Dead center in the picture is the Pleiades, the small cluster of bright stars. The bright object is the Moon, and to the lower right is Venus. If you look carefully, just above the horizon, lies Jupiter. To see it, start at the Pleiades, let your eyes move down and to the right to Venus, then keep going; Jupiter is in line with the clouds, just at the edge of the aurora itself.
I love how that one long swooshing ribbon of aurora cuts across the whole picture. See how it looks broader to the left, then narrower as you follow it to the right? That’s almost certainly perspective making it looks smaller. It’s probably something like 100 kilometers (60 miles) above the Earth’s surface and follows the Earth’s curve. The far end of it, near the horizon, is much farther away than the part at the upper left.
And despite all the drama occurring in the sky, my eye keeps getting drawn to the water. In this 10 second exposure, the slow movement of the water softens its appearance. Funny, too: I saw a face in the water and chuckled, then noted that Mortensen got a note from a friend who saw the face as well… or maybe a different one. But the one I see is pretty obvious. Do you see it too?
Mortensen has many more beautiful shots of aurorae on his 500px page, so head over there and soak up the glory of the active sky.
Image credit: Helge Mortensen, used by permission.
I have got to get to Norway. Last year, on September 25, 2011 from Ifjord, Finnmark, Norway, photographer Tommy Eliassen took this jaw-dropping photo of the night sky:
[Click to enstupefyenate.]
I know, seriously, right?
The northern lights play along the right while the Milky Way itself hangs vertically next to it; parallel structures seemingly adjacent but separated by thousands of trillions of kilometers…
And to top it off, a meteor plinks across the sky between them. Meteors burn up about 100 km or so above our planet’s surface, which is at just about the same altitude that’s the lower limit of green aurorae. Amazingly, that meteor is probably the closest thing you can see in this picture above the clouds*.
Image credit: Tommy Eliassen, used by permission.
* Since it cuts across the two parallel background objects at an angle, it must be a skewting star.
Troms, Norway is pretty far north — at a latitude of 70°, it’s above the Arctic Circle, and in January the Sun never rises. That might sound forbidding, but this video by Ville Kröger of the aurorae taken in January during the big solar storms might change your mind:
What breathtaking scenery! The mountains look wonderful, and I imagine it’s a lovely place to visit… in the spring, or in the winter to see the northern lights. Funny — it gets colder here in Boulder on average than it does there. Latitude isn’t everything; sea currents make a big difference as well.
But of course, we don’t get the light show they do. Someday I’ll get to see one of these. Sigh.
Yesterday was St. Patrick’s Day, a holiday in the US traditionally celebrated by wearing green and drinking too much. In that spirit, how about a nice, soothing time lapse video of green aurora?
Some of the spinning scenes of stars may not qualm the upset tummies out there post-festivities, but it probably also doesn’t help to think of the vast energies and quantum mechanics playing out over your head every day as our whirling planet geodynamically interacts with the wind from the Sun screaming across the solar system at million of kilometers per hour, either.
Around 04:00 UTC on Monday morning, January 23, 2012, the Sun let loose a pretty big flare and coronal mass ejection. Although there have been bigger events in recent months, this one happened to line up in such a way that the blast of subatomic particles unleashed headed straight for Earth. It’s causing what may be the biggest space weather event in the past several years for Earth: people at high latitudes can expect lots of bright and beautiful aurorae.
I’ll explain what all that is in a second, but first here’s a video of what this looked like from NASA’s SOHO satellite.
Wow! Make sure you set it to high def.
So what happened here? The sunspot cluster called Active Region 11402 happened.
Sunspots are regions where the magnetic field lines of the Sun get tangled up. A vast amount of energy is stored in these lines, and if they get squeezed too much, they can release that energy all at once. When this happens, we call it a solar flare, and it can be mind-numbing: yesterday’s flare exploded with the energy of hundreds of millions of nuclear bombs!
In the image above, the sunspots are caught in mid-flare, seen in the far ultraviolet by NASA’s Solar Dynamics Observatory (it’s colored green to make it easier to see what’s what). We think of sunspots as being dark (see the image of AR 11402 below), but that’s only in visible light, the kind we see. In more energetic ultraviolet light, they are brilliant bright due to their magnetic activity.
A huge blast of subatomic particles was accelerated by the explosion. The first wave arrived within a few of hours of the light itself… meaning they were traveling at a significant fraction of the speed of light!
But shortly after the flare there was a coronal mass ejection: a larger scale but somewhat less intense event. This also launches particles into space, and these are aimed right at us. The bulk of the particles are traveling at slower speeds — a mere 2200 km/sec, or 5 million miles per hour — and is expected to hit us at 14:00 UTC Tuesday morning or so. That’s basically now as I write this! Those particles interact with Earth’s magnetic field in a complicated process that sends them sleeting down into our atmosphere. We’re in no real danger from this, but the particles can
strip the electrons off of atoms high in the air, and when the electrons recombine the atoms glow excite the electrons in atoms high in the air, and when the electrons give up that energy the atoms glow. That’s what causes the aurorae — the northern and southern lights.
If you live in high latitudes you might be able to see quite the display when it’s dark — people in eastern Europe and Asia are favored for this, since this happens after sunset there. But the storm is big enough and will probably last long enough that everyone should check after dark: look north if you live in the northern hemisphere and south if you’re south of the Equator. There’s no way in advance to know just how big this will be; it might fizzle, or it might be possible to see it farther away from the poles than usual. Can’t hurt to look! Also, Universe Today has been collecting pictures of aurorae from the solar blast earlier this week. No doubt they’ll have more from this one as well.
Although big, this flare was classified by NASA as being about M9 class — powerful, but not as energetic as an X class flare. One of those popped off last September, and shortly after that a smaller M flare erupted, which also triggered a gorgeous plasma fountain called a filament on the Sun’s surface.
As I said, we’re in no real danger here on Earth, and Universe Today has a good article describing why the astronauts are probably not in danger on the space station, either. Even if this were larger storm, the astronauts can take shelter in more well-protected parts of the station, too. Bigger storms can hurt us even on Earth by inducing huge currents in power lines which can overload the grid. That does happen — it happened in Quebec in March of 1989 — and it may very well happen again as the Sun gets more active over the next few years. [UPDATE: a ground current surge from today's event was reported in Norway.]
But we should be OK from this one. If you can, get outside and look for the aurorae! I’ve never seen a good one, and I’m still hoping this solar cycle will let me see my first.
Image credit: NASA/SOHO; NASA/SDO
Some pictures really go the extra mile (1.6 kilometers) when capturing the beauty of nature. This picture, by Stephane Vetter, goes even farther than that:
How about that? There’s so much to see in this picture from southern Iceland (and click to embiggen and get the amazing and beautiful details).
First, I love the waterfall; in time exposures the frothy water takes on an almost satin-like quality, silky, milky, and smooth. It can be hard to get long time exposures during the day, but in this case the water was lit by the Moon at night!
But wait a sec: if it’s night, why is there a rainbow?
There isn’t! That’s a moonbow, caused by aerosolized water droplets at the base of the falls hanging in the air and acting like little prisms, bending the moonlight and splitting it into its colors. Moonbows are pretty faint, so it takes a time exposure like this to be able to discern them clearly.
Looking up, you can also see some stars — the Big Dipper is just above the rocks on the left — as well as the faint green glow of the aurorae. All in all, there’s a little bit of everything in this picture… well, almost everything.
It’s amazing what you can see if you just go out and look. I don’t like to use the word magic, because it’s burdened with meaning that is the exact opposite of science, but really the term "magical" might be appropriate here. In that sense, it triggers our wonder and sense of beauty, our awe of nature. That’s precisely what I feel when I see pictures like this. It can be beautiful outside, so go see.
Speaking of solar storms causing gorgeous auroral displays…
In late October, a coronal mass ejection (CME) — a violent explosion of subatomic particles erupting from the Sun at high speeds — blasted away from our star, impacting the Earth, and setting off aurorae seen as far south as Arkansas. It was cloudy here in Boulder, but from space, the view is always clear. NASA’s STEREO spacecraft are twin machines, one ahead of the Earth, one behind, both staring at the Sun 24/7. They are currently roughly 100° around the Earth’s orbit, so they are essentially seeing the Sun "from the side".
STEREO A, ahead of the Earth in its orbit, captured images of the Sun during October’s solar hissy fit, and got dramatic footage of the explosion:
Yegads. [Make sure you click the HD button to see this in all its glory.]
The Earth is off to the left, well off-screen, in this animation. The Sun is blocked by a circular mask, so fainter things can be seen (its disk is represented by the white circle). The big CME occurred early on October 22 and is followed by others.
[Make sure you set it to HD and make it full screen.]
Wow! That’s amazing. Did you catch the Andromeda Galaxy making an appearance at 1:25 in, at the middle left of the screen? Maybe you missed it because of THE GINORMOUSLY BRIGHT AND GORGEOUS AURORAE.
As a travel ad, this works pretty well (it was made by Flatlight Films, a Finnish company). Living in Boulder, I’m used to the cold, but we always seem to just miss being far enough north to see the light show. And we still have a couple of years before we even reach the peak of solar activity, so there’ll be plenty of chances to catch more.
[P.S. If you're on G+, follow Fraser. He's good people.]