At 11:12 UT (6:12 a.m. EST), the world didn’t end (as far as I can tell), but it was a significant time none-the-less. That was the exact minute of the Winter Solstice in the Northern Hemisphere (or the Summer Solstice in the Southern Hemisphere) — when the daylight hours are shortest and the sun reaches its most southern position in the sky at noon. This is all due to the Earth’s tilt relative to the sun (read more on the Earth’s axial tilt and how it affects the seasons).
The ever-watchful NASA Solar Dynamics Observatory (SDO) captured the time of solstice from orbit. Although the SDO is always imaging the sun through a multitude of filters, this is a great excuse to showcase the fantastic beauty of our nearest star, while putting all the doomsday nonsense behind us.
The sun didn’t unleash a killer solar flare or devastating coronal mass ejection, but it is undergoing a fascinating period in its solar cycle.
As can be seen from the SDO image above, the solar magnetic field is twisted and warped, channeling million-degree plasma high into the sun’s atmosphere in the form of beautiful coronal loops. This is all because the sun is fast approaching “solar maximum” — an exciting time when the sun’s magnetic field is most stressed.
We can expect a lot more flares and CMEs from now and through 2013; although these events can damage satellites and threaten power supplies, they’re not the flares described in doomsday myth.
So sit back, and enjoy some solar science and spectacular views of our star as it enters the most dramatic time of its cycle.
Image: The sun as seen through the SDO’s 171A filter. Credit: NASA/SDO