Tonight's Perseid Meteor Shower May Be Dipped in Aurora Sauce

On Sunday night, August 11-12, the annual Perseid blast will crest to a peak. Dozens of meteors will flash across the sky per hour especially after midnight, when the crescent Moon sets and the shower's streaming point climbs high in the northeastern sky. That's not all. In what could be a spectacular two-fer, there's an excellent possibility that roughly the northern third of the U.S. will also experience a G2 geomagnetic storm with aurora visible as far south as New York, Idaho and northern Iowa. Aurora and Perseids at the same time? Now that would be exciting!

Last night, the NOAA spaceweather forecast called for a similar moderate storm. At the time I was attending the annual Voyageurs Star Party at Voyageurs National Park near International Falls, Minnesota. Voyageurs received Dark Sky Park certification in 2020. Its pristine skies and location near the Canadian border make it one of the premier aurora-watching locations in the country.

As per forecast, the aurora first became visible at nightfall but remained fainter than expected and hovered low in the northern sky — until 11:30-midnight. All at once, the humdrum green arc thickened, brightened and grew faint, feather-like rays. They appeared pale white with the naked eye — as does so much of the aurora unless the storm intensifies — but glowed a luscious red in time-exposures made with the camera. After a half-hour of slow-dancing the lights reverted to featureless mush. Was the show over? Not by a long shot.

We waited and waited some more. Happily, around 1 a.m. the sky busted open. A reenergized green arc splintered into tall green and red rays so intense the colors were immediately obvious to the eye. As if on cue, Jupiter and Mars rose together and added a double-dash of beauty to the scene. Not to forget the Perseids. While we saw them zip past all night, their numbers increasing with each passing hour. Had I watched alone, I don't think I would have been able to keep track of such a busy sky. But with a half-dozen or so additional pairs of eyes we had it covered. Not to mention how much observing's fun factor increases when shared with other enthusiasts.

A steady stream of coronal mass ejections in the wake of solar flares from a VERY active and spotty Sun were behind the August 10-11 aurora and also what we may experience Sunday night, August 11-12. For your best chance at seeing the aurora, find a location with a dark northern sky so the cosmic lights don't have to compete with city light pollution. Bring a camera. Any camera. If you hold your smartphone to the sky it automatically will put itself in dark mode (or can be put in dark mode) and let you do handheld, 3-second-long time exposures. On an iPhone, if you tap the small white triangle at the top of the screen, it will open up a menu where you can expose up to 10 seconds — plenty of time to record a moderately bright aurora and colors. Be sure to tap your screen to focus the starry sky when your ready to take a picture.

With a DSLR or mirrorless camera and tripod it's super-easy to photograph the aurora. First, put everything in manual mode — lens and exposure selection alike. Then click the live-view button, center a bright star on the camera's backscreen, magnify it with the magnifier button and manually focus your lens until the star is a tight point. You're now ready to go! Try ISO 2500 with the lens wide open (f/3.5, 2.8 or 2) and an exposure of 10-15 seconds. Adjust as needed depending on the aurora's appearance on the backscreen.

Sunday night's aurora is expected to begin around 9:30-10 p.m. CDT at the minor storm level (G1) and then ramp up to a G2. Well after midnight it will decline to a G1 and linger until dawn. Should the forecast be dead-on (never a guarantee) the lights may become more intense and widespread than Saturday night's event. Let's hope so. And if not, you'll still have a great meteor shower to see plus Jupiter and Mars as icing on the cake. If you capture either aurora or a Perseid — or hopefully both at the same time — please share your image and comments with Sky & Telescope. Good luck!