Best time of night for the aurora: magnetic midnight and the moon

The aurora can appear the moment the sky is dark enough, and during the polar night some of the best evenings start around dinner time. But the strongest and most dynamic outbursts cluster around what is called magnetic midnight. In Northern Norway that falls at roughly 11 pm Norwegian winter time, a little earlier in Finnmark and a little later in Lofoten. The best strategy is to be out from the moment it gets dark, but to make sure you are still out between about 10 pm and 1 am.

Why midnight? The auroral oval stays put while we rotate

The aurora forms in a ring around the magnetic pole, the auroral oval. The oval stays roughly fixed relative to the sun while the Earth turns underneath it. The part of the oval facing away from the sun, on the night side, is both the widest and the most active, because that is where energy stored in Earth's magnetic tail is released. More on this in what is the aurora.

The centre of the night side follows Earth's magnetic axis, not the clock. That is why scientists use magnetic local time, and magnetic midnight is the moment your location sits right on the night side of the oval.

NOAA's Space Weather Prediction Center says the best aurora is usually within an hour or two of midnight, between 10 pm and 2 am local time, and that this window widens towards evening and morning when activity is high. That rule of thumb is written for North America, so we worked out the numbers for Norway ourselves.

Magnetic midnight in Northern Norway

We calculated magnetic midnight with the AACGM-v2 coordinate model, widely used in aurora research, for an altitude of 110 km, where the aurora typically glows. The result, in Norwegian winter time (UTC+1):

The earlier time applies in autumn, the later in midwinter. Other coordinate models give somewhat different numbers, so treat this as a range rather than an exact time. Visit Lofoten itself says the aurora there typically appears between 6 pm and 1 am, with the best chance around 10–11 pm in winter.

Mind daylight saving time: until the last Sunday in October and from the last Sunday in March, Norwegian clocks are one hour ahead. In September and early October, magnetic midnight in Tromsø is therefore closer to 12:05–12:30 am on the clock.

How a typical aurora night unfolds

NOAA's walk-through of the aurora's phases describes a pattern many aurora hunters will recognise:

• Evening: Quiet arcs, often one or more green bands stretching east to west. They can hang in the sky for a long time without moving much.
• Around midnight: The arcs begin to ripple and fold. During a so-called substorm the aurora can suddenly brighten, spread across the sky and dance in swirls and curtains. Each outburst comes with a surge of activity travelling westward. On active nights there can be several of them.
• After midnight and towards morning: The aurora becomes more diffuse and patchy. The patches often pulsate, switching on and off within seconds, and can continue until dawn.

The most intense phase of an outburst can be over within minutes, although the aurora often flares up again later. If you went inside to warm up at that exact moment, you missed it. Morning aurora is fainter, but worth a glance out of the window if you wake early.

Darkness decides when the evening starts

How early you can start depends on the season. As a rule, the sun needs to be at least 12° below the horizon (the end of nautical twilight) before faint aurora is easy to see. Our calculations for Tromsø give roughly these windows of nautical darkness, in local time:

• 15 September: about 9:45 pm–3:30 am (summer time)
• 15 October: about 7:15 pm–5:45 am (summer time)
• 15 November: about 4:25 pm–6:35 am
• 15 January: about 4:20 pm–7:25 am
• 15 February: about 6:00 pm–5:55 am
• 15 March: about 7:55 pm–3:50 am
• 1 April: about 10:30 pm–3:05 am (summer time)

In September and April the whole aurora night is squeezed around midnight. In midwinter you have many hours to play with. See best time of year for the full season.

The moon: a nuisance, not a showstopper

A full moon brightens the sky and makes faint aurora look paler to the eye. NOAA points out that the moon affects how bright the aurora appears, not how bright it actually is. A strong outburst is easy to see under a full moon.

In Northern Norway the moon is a particular factor in midwinter, when the full moon rides high and can stay up around the clock. The full moon of 24 December 2026, for example, does not set at all in Tromsø, according to our calculations.

Full moons in the 2026–27 season (from the U.S. Naval Observatory, Norwegian date): 26 October, 24 November, 24 December, 22 January, 21 February and 22 March. New moons, with the darkest skies, are on 9 November, 9 December, 7 January, 6 February and 8 March.

For photographers the moon is not all bad: a little moonlight draws out mountains and snow and gives pictures more depth. See photographing the aurora with a camera.

How long should you wait?

A good aurora evening is rarely a quick step outside. Some practical advice:

• Go out when it is dark enough, but plan to stay until at least 12:30 am, and longer on high-activity nights.
• Check real-time data, not just the daily forecast. Solar wind data give a short heads-up that something is on its way; see solar wind, Bz and speed.
• Dress to stand still for several hours, with extra layers in your bag and a hot drink. See safety and clothing.
• Look north and east early in the evening. When the outburst comes, it can fill the whole sky, including straight overhead.
• Give your eyes time to adjust to the dark, and avoid staring at a bright phone screen.

In short

• Be out as soon as it is dark, but prioritise the time around magnetic midnight, roughly 10:30 pm to midnight Norwegian winter time.
• On summer time (September, October and from late March) add an hour.
• Outbursts start suddenly and often peak briefly; patience pays.
• A full moon dims faint aurora but does not stop a strong display.
• Before you head out: check tonight's verdict for your location.