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Check my feed every day this month for a daily "comet tracker" with finder charts and tips for viewing Comet Lemmon and Comet SWAN from mid-northern latitudes. Also read How To Photograph The Green Comets, Best Stargazing Apps For Finding The Comets and 25 Dark Sky Parks In The U.S. To See The Comets.
The Northern Lights may be visible from northern U.S. states and Canada after dark on Saturday, Oct. 18 through Sunday, Oct. 19, 2025, according to a forecast from the National Oceanic and Atmospheric Administration's Space Weather Prediction Center (SWPC). The forecast includes "unsettled to active geomagnetic activity" including the possibility of a G1-rated geomagnetic storm.
The forecast comes as two comets -- Lemmon (C/2025 A6) and SWAN (C/2025 R2) -- are brightening in post-sunset skies as seen from across the Northern Hemisphere, though both require binoculars. Skywatchers may also see occasional "shooting stars" from the Orionid meteor shower, which peaks on Monday, Oct. 20.
Spaceweather.com is reporting that Comet Lemmon has increased in brightness to magnitude +4.5, which will make it easier to see and photograph this weekend -- possibly with aurora in the background.
The latest forecast has a possible G1 geomagnetic storm on Saturday, Oct. 18 through Sunday, Oct. 19 as the lingering effect of two small coronal mass ejections that were hurled from the sun in the direction of Earth on Oct. 13. A CME is a cloud of magnetic fields and charged particles from the sun that stream into space at up to 1,900 miles (3,000 kilometers) per second.
"A chance for G1 (Minor) storming, is expected on 18 Oct with any glancing CME effects causing these activity levels to carry over into the early portions of 19 Oct.," states NOAA. In the weeks after the September equinox, geomagnetic activity is often amplified by celestial geometry. It could mean that the auroral oval is pushed farther south than usual.
U.S. states that may see aurora include Alaska and (northerly parts of) Washington, Idaho, Montana, Wyoming, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, New York and Maine. However, all forecasts for the aurora must be treated with caution. To check visibility in real time, use NOAA's 30-minute aurora forecast, or download apps such as Aurora Now, My Aurora Forecast or Glendale Aurora for up-to-the-minute alerts and live solar wind data.
A mirrorless or DSLR camera is ideal (ISO 1600, 2-10 seconds, f2.8), though newer smartphones are increasingly capable of stunning results. If your smartphone has a Night Mode or Pro Mode, you can capture a beautiful aurora photo with these steps:
Aurora, comets and "shooting stars" are greatly affected by urban light pollution, so use a light pollution map or visit a Dark Sky Park for the best views. The most important aspect is a dark northern, northwest and southwest horizon -- don't try to look for aurora or comets while east or south of a big city.
To photograph a comet, you'll need to use either a smartphone or a manual mirrorless or DSLR camera. If mounted on a tripod or similar, a smartphone's "night mode" or "pro mode" will take a long exposure (likely 30 seconds) and probably find the comet. If your smartphone has a RAW mode, use it -- but the tripod is critical.
Remarkably, a smartphone is also really handy to help you find the comet with a pair of binoculars, because even a handheld three-second exposure -- which most smartphones can offer -- will reveal a fuzzy blob.
For a manual camera, try ISO 800-1600, f/2.8-f/4 aperture, and a shutter speed of 10-30 seconds.