The aurora is a beautiful, if hard to predict, phenomenon, occurring year-round.
In Alaska, summers are marked by extremely long days. Thus, only in the fall, winter and early spring is there enough darkness to allow a chance of seeing the northern lights.
How to See Aurora
Aurora viewing takes luck and patience.
In general, viewing is more likely the farther north you are, as the phenomenon takes place around the poles. Sometimes aurora is active as far south as the upper midwest of the United States, but this is rare.
In Denali National Park, skies are dark enough from roughly mid-August to mid-April for good chances of aurora viewing. Visitors traveling to the park in June or July will certainly not see aurora, as it is far too bright that time of year.
Learn more about how, when, and where to see the aurora and consult one of several aurora forecasts to get an idea of how likely it is you'll see aurora (note: these forecasts, like weather forecasts, can be changeable and are looking mainly at the short-term, e.g., 3 days to a week).
The Science of AuroraThe aurora borealis (northern lights) occurs when a coronal mass ejection (CME), a massive burst of solar wind and magnetic fields, interacts with elements in the earth's atmosphere. Coronal mass ejections are often associated with other forms of solar activity, most notably solar flares. Near solar maxima the sun produces about three CMEs every day, whereas near solar minima there is about one CME every five days. Solar winds stream away from the sun at speeds of about 1 million miles per hour and reach the earth roughly 40 hours after leaving the sun. As the electrons enter the earth's upper atmosphere, they will encounter atoms of oxygen and nitrogen at altitudes from 20 to 200 miles above the earth's surface. The color of the aurora depends on which atom is struck, and the altitude of the meeting.
- Green - oxygen, up to 150 miles in altitude
- Red - oxygen, above 150 miles in altitude
- Blue - nitrogen, up to 60 miles in altitude
- Purple/violet - nitrogen, above 60 miles in altitude
The auroras generally occur along the auroral ovals, which center on the magnetic poles and roughly correspond with the Arctic and Antarctic circles. The lights can be visible at lower latitudes when solar activity is high.
In Denali National Park, pets are permitted on roads (when leashed) and in personal vehicles.
If you are viewing aurora elsewhere, check in advance to see if pets are permitted or not.
When you're in mainland Alaska, anywhere away from city lights is a decent place to hope for aurora viewing on a clear, dark night.
A few unpredictable things are needed to see the aurora:
- Dark enough
Alaska is bright in the summer, with the sun up around-the-clock above the Arctic Circle and days nearly as long just below the Arctic. In Denali, it is too bright to see the aurora in June and July, and is too bright for most of May and August.
- Clear enough
Even if the sky is dark, too many clouds will ruin your viewing opportunity. Clear skies are more common in the middle of winter, when the air is often very dry, but there can be plenty of clear nights in fall and spring, too.
- Aurora-y enough
The aurora happens year-round, and it can be forecast. Sometimes there is little or no auroral activity, and at other times it can be very active. Search "aurora forecast" with your favorite search engine to pick from among the many forecasting services on the internet.
Last updated: December 31, 2020