December 17, 2012
Solar Wind Storms Earth, Enhances Northern Lights
Lee Rannals for redOrbit.com — Your Universe Online
The solar wind that Earth is passing through has forecasters from the NOAA estimating a slight 20 percent chance of geomagnetic storms, but NASA says that high-latitude residents could benefit from the event.
Sky watchers may want to step out into their backyards for the next few nights to catch a glimpse of the Auroras, or the "Northern Lights" (or Aurora Borealis).
The Sun's activity has a direct impact on the Northern Lights, and, essentially, the more active the Sun, the more active the Aurora Borealis.
The stream of solar wind derived from corona holes on the Sun, which are regions where the corona is dark.
These holes were discovered when X-ray telescopes were first flown above the Earth's atmosphere to reveal the structure of the corona across the solar disc, according to NASA.
Coronal holes are associated with "open" magnetic field lines, and are often found at the Sun's poles. The high-speed solar wind is known to orientate in coronal holes.
NASA released a composite image taken by its Solar Dynamics Observatory (SDO) that shows a closer look at the coronal hole culprit.