Some photos inspire both awe and terror. The two emotions ride back to back when it comes to our experience of nature. For your Halloween pleasure, I wanted to share these several images, one of an aurora over Iceland, and the other a fleeting eclipse of the “black moon” across the face of the sun and another of interstellar ghosts.
The curled form of the aurora recalls the giant serpent in the Harry Potter movies. That and the extremely short exposure of just 3 seconds gives the photo a bizarre, unreal look despite the fact that the photographer didn’t manipulate the image. Many aurora photos are exposed around 15-30 seconds. Because bright auroras are often on the move, longish times exposures gives them a soft, melty appearance. These are crystalline sharp because they were so bright that a 3-second exposure did the job. The pins and needles texture is very close to a bright, active aurora’s appearance in real time.
The lights were photographed over a town in southern Iceland named Selfoss and show multiple, narrow rays that reveal the path that electrons in the solar wind are using to stream down into our atmosphere. They’re all scrunched together because the particles are streaming down zillions of approximately parallel magnetic field lines that meet our planet at its poles. The same bunching of field lines is revealed when you sprinkle iron filings at the pole ends of a bar magnet.
Our next spooky photo was taken yesterday by NASA’s Solar Dynamics Explorer (SDO) satellite, with a tilted orbit in the geosynchronous satellite belt a little more than 22,000 miles away. From SDO’s point of view, the moon lined up with the sun to make for a partial solar eclipse lasting about an hour. Notice that the sun appears to be shaking slightly – spooked perhaps by the black form rushing by? Instead, the shaking results from slight adjustments in SDO’s guidance system, which normally relies upon viewing the entire sun to center the images between exposures. SDO captured these images in extreme ultraviolet light which is invisible to human eyes.
The final photo is one of my favorite scary cosmic images and depicts the Ghost Nebula in the constellation Cepheus the King. You’re seeing a cloud of cosmic dust shining by the reflected light from stars that lie within and close to the nebula. The flailing forms at left are most evocative.
Have fun with all the little ghosties and ghoulies tonight!