Starship Asterisk*

Little Planet Aurora

Explanation: Immersed in an eerie greenish light, this rugged little planet appears to be home to stunning water falls and an impossibly tall mountain. It's planet Earth of course. On the night of November 9 the nadir-centered 360 degree mosaic was captured by digital camera from the Kirkjufell mountain area of western Iceland. Curtains of shimmering Aurora Borealis or Northern Lights provide the pale greenish illumination. The intense auroral display was caused by solar activity that rocked Earth's magnetosphere in early November and produced strong geomagnetic storms. Kirkjufell mountain itself stands at the top of the stereographic projection's circular horizon. Northern hemisphere skygazers will recognize the familiar stars of the Big Dipper just above Kirkjufell's peak. At lower right the compact Pleiades star cluster and truly giant planet Jupiter also shine in this little planet's night sky.

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The lines of the aurora are reminiscent of magnetic flux lines, arcing out from the poles just as they do on the ends of a magnet. Is there any relationship between those aurora lines and Earth's magnetic flux lines?

SeedsofEarfth wrote: ↑Sat Nov 25, 2023 2:59 pm The lines of the aurora are reminiscent of magnetic flux lines, arcing out from the poles just as they do on the ends of a magnet. Is there any relationship between those aurora lines and Earth's magnetic flux lines?

Not sure. The aurora is certainly caused by Earth's magnetic field, but whether or not the strong resemblance here to the shape of those field lines (looping from pole to pole) is revealing that is unclear to me. It may just be a trick caused by the stereographic projection. Chris?

johnnydeep wrote: ↑Sat Nov 25, 2023 9:38 pm

SeedsofEarfth wrote: ↑Sat Nov 25, 2023 2:59 pm The lines of the aurora are reminiscent of magnetic flux lines, arcing out from the poles just as they do on the ends of a magnet. Is there any relationship between those aurora lines and Earth's magnetic flux lines?

Not sure. The aurora is certainly caused by Earth's magnetic field, but whether or not the strong resemblance here to the shape of those field lines (looping from pole to pole) is revealing that. It may just be a trick caused by the stereographic projection. Chris?

Click to view full size image

While the charged particles that create auroras certainly travel along magnetic field lines, I do think this largely an illusion here. Superficially this image looks like the lines around a bar magnet- a dipole field with a north and a south. But the south magnetic pole is not close to being visible here!

Chris Peterson wrote: ↑Sat Nov 25, 2023 9:57 pm

johnnydeep wrote: ↑Sat Nov 25, 2023 9:38 pm

SeedsofEarfth wrote: ↑Sat Nov 25, 2023 2:59 pm The lines of the aurora are reminiscent of magnetic flux lines, arcing out from the poles just as they do on the ends of a magnet. Is there any relationship between those aurora lines and Earth's magnetic flux lines?

Not sure. The aurora is certainly caused by Earth's magnetic field, but whether or not the strong resemblance here to the shape of those field lines (looping from pole to pole) is revealing that is unclear to me. It may just be a trick caused by the stereographic projection. Chris?

Click to view full size image

While the charged particles that create auroras certainly travel along magnetic field lines, I do think this largely an illusion here. Superficially this image looks like the lines around a bar magnet- a dipole field with a north and a south. But the south magnetic pole is not close to being visible here!

Ah, thanks. Good point!