June 1, 2013 Clouds/Auroras
Highway 38, north of Grand Rapids
For the first time in nearly a year (or so it seemed), a geoeffective coronal hole opened up on the sun. These holes are often preceded by a corotating interactive region, which contains a higher density of solar wind particles due to a faster solar wind stream coming out of the coronal hole and converging with a slower solar wind. In this corotating interactive region, the interplanetary magnetic field often drops south, bringing auroras to latitudes more equatorward than is normally the case. This is exactly what happened on May 31 as the magnetic field dropped south before the arrival of the high speed stream from the hole pictured below.
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| The dark spot in this image is a coronal hole. Image courtesy of the Solar Dynamics Observatory. |
Unfortunately, the clouds mostly foiled my plans of seeing the ensuing auroras. I waited until sunset to pick a place for photography, and by then, I could see auroras shining through breaks in the cloud deck. I drove north on Highway 38 to find a spot to shoot and ended up at the former Wilderness Pub parking lot. Through the clouds, I could see the green glow, so I knew the show had to be intense. I just couldn't see any structure. The clouds did break a little but then filled back in, and then it started to rain. I fired off a few shots from Pughole Lake before the rain arrived.
Farther south, though, the clouds were not as much of a problem, and the auroras put on one of the best shows of Solar Cycle 24. Bill Doms captured some very stunning images of these colorful auroras.
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| Auroras through breaks in the clouds, looking west from the Wilderness Pub parking lot. The auroral oval extends from just above the trees in the center of the shot to the upper right corner. |
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| Looking east over Pughole Lake with the auroral oval running from the eastern horizon directly overhead. The more orange-colored lights along the horizon on the rightmost 40 percent of the image are mostly city lights. |