Scientists Expose Mystery Behind Aurora Borealis Spectacle Of Light

The enigmatic aurora borealis has kept scientists on a constant quest to understand the mysterious forces behind the spectacular dance of lights that brightens the North sky at night. Auroras can be observed near the Earth’s northern (aurora borealis) and southern (aurora australis) magnetic poles, in colorful green, blue or red displays.

The spectacular events have been linked to geomagnetic substorms, which are powered by explosions of magnetic energy one third of the way to the moon. This triggers the magnetic reconnection phenomenon, when magnetic field lines merge into new shapes, causing the sudden brightening and movement of the aurora borealis.

“We discovered what makes the Northern Lights dance,” said Dr. Vassilis Angelopoulos of the University of California, Los Angeles. Scientists have been trying for decades to find out what exactly triggers the burst of energy in Earth’s magnetosphere.

With the help of the NASA THEMIS satellites, short for Time History of Events and Macroscale Interactions during Substorms, researchers identified the magnetic explosions that produce dynamic changes in the auroral displays.

Scientists Expose Mystery Behind Aurora Borealis Spectacle Of Light.

David Sibeck, THEMIS project scientist at NASA’s Goddard Space Flight Center, explained that the magnetic reconnection releases the energy captured and stored by Earth’s magnetic field lines from the solar wind back toward the Earth’s atmosphere, which creates halos of shimmering auroras circling the northern and southern poles.

Prior to the observations from the THEMIS satellites, there have been two theories regarding the substorms. One theory placed substorms closer to Earth, one-sixth of the way to the moon, where large amounts of particles are sent toward our planet from solar wind currents’ disruptions, causing the burst of light.

The second theory, confirmed by this study, places the substorms one third of the distance to the moon, where magnetic lines are stretched so far back that they snap into a new shape, similar to a rubber band when it is stretched too far, in a phenomenon known as magnetic reconnection.

This is from over a month back, but I really wanted to mention it, both here and on the video.  I can explain what his happening there a bit better, using the pictures below, but I always find it exciting when we solve another of the great mysteries.

Simple Version of the Earth's Magnetic Field

Simple Version of the Earth's Magnetic Field

Complex Version of the Earth's Magnetic field

Complex Version of the Earth's Magnetic Field

UPDATE: You can see the video version of this post in these videos. This post is covered in the second one.

Matrix .01 Coming Soon

I Saw The Future Of Social Networking The Other Day

But it’s coming. A few years from now we’ll use our mobile devices to help us remember details of people we know, but not well. And it will help us meet new people for dating, business and friendship. Imagine walking into a meeting, classroom, party, bar, subway station, airplane, etc. and seeing profile information about other people in the area, depending on privacy settings. Picture, name, dating status, resume information, etc. The information that is available would be relevant to the setting – quick LinkedIn-type information for a business meeting v. Facebook dating status for a bar.

That requires a social network that has presence, location and contextual information about you. It needs to know where you are (via GPS or triangulation), if you are in business or personal mode, and similar information for the people around you. It also needs, at a basic level, the ability to sort and browse the people around you based on their picture and name, and what they are looking for (dating, investments, job, friendship). Once this network is established, you’ll know everyone’s name who’s around you (if they choose to share it), and enough basic information to jog your memory if you know them, or meet them if there’s mutual interest. Poking someone on Facebook is great, but “poking” them when you’re in the same bar as them can result in much more immediate social gratification.

If you would like a novel-lenght exploration of some of the potential for the tech here,  I would recommend reading “Halting State” by Charlie Stoss. Tease yourself here.

Prologue: We know where you live, we know where your dog goes to school

Chapter 1: Grand Theft Auto

Chapter 2: Stitched Up

Chapter 3: Steaming

Taking Pictures of Energy

Attosecond Physics & High-Order Harmonic Generation

In Lund, we are performing basic research in a very exciting field at the border between atomic and molecular physics and advanced optics, nonlinear optics and laser physics: high-order harmonic generation in gaseous media exposed to intense laser fields and its applications. The harmonic spectrum exhibits an extended “plateau” where consecutive (odd) harmonics have approximately the same intensity. If the harmonics are emitted in phase, i.e. phase-locked, the temporal structure of the radiation emitted from the medium consists of a “train” of attosecond pulses separated by half the laser period

Follow-up to this post.

 I can’t wait till you all figure out that time is an illusion.  That’s when things get interesting.  I love to read how you people can figure out this stuff, but still haven’t figured out that every robot breaks down and is going to need repair and that it is much more efficient to pool resources to deal wtih such an obvious eventuality….but that’s neither attosecond or quantum physics and has no place in this post.