It is often said that if one goes to the North or South Pole then the sun never rises (or sets depending on the season). But where can one see this? How far north does one need to go for the sun not to rise above the horizon?
In short, the answer is really really far. In fact, it is much further north than one needs to go to see the Northern Lights (that one can see in Alaska and Canada). It is possible to see it in the United States and there are some other places in the world that are perhaps more accessible.
The polar night is when the nighttime lasts for over 24 hours (when the sun does not rise at all and all day in the depth of winter it is only darkness. The opposite of this is the polar day (or midnight sun) when the Sun remains above the horizon and there is no darkness during the night.
- Amundsen-Scott South Pole Station: The Only Permanent Settlement That Experiences Astronomical Polar Nights
The sun does not need to be above the horizon for there to be light, this is because the atmosphere refracts sunlight. A consequence of this is that the polar day is actually longer than the polar night (and the zone of the polar nights is a bit smaller than the zone for the midnight sun).
In the Northern Hemisphere, the latitude is approximately 66.5 degrees.
The types of Polar Twilight are:
- Civil Polar Night: When Only a Faint Glow is Visible At Midday
- Nautical Polar Night: When There Is No Daylight Except Around Midday
- Astronomical Polar Night: Continuous Night (The Sun Is Below 18 Degrees Over The Horizon
Civil Polar Twilight
There are various kinds of twilight and what is perceived by observers on the ground is affected by factors like the presence of dense clouds. Twilight is defined as the illumination of the lower atmosphere when the Sun is below the horizon - it is produced by the sunlight scattering in the upper atmosphere.
This is a state when the Earth's surface is neither completely lit nor is it completely dark. It's why when the sun sets it continues to be bright for a while afterward.
- Farthest South: 67°24’ To See The Polar Twilight
Polar twilight occurs in areas that are located in the inner border of the polar circles on the winter solstice. At this time the sun is below or on the horizon all day. In these dark days of winter, the sun is not visible all day long, but there is still light for a time at midday, even though people on the surface will not see the sun at all.
- Polar Twilight: When The Sun Is Below The Horizon, but By Less Than 6° On The Winter Solstice
For this to happen the sun must be below the horizon but no more than 6 degrees. During the Polar Twilight, street lamps may remain on but the outdoor illuminance is less than that of a brightly lit room.
- Occurrence: At Latitude Between 67°24’ and 72°34’ North or South
Northern Hemisphere Polar Twilight Latitudes:
- 68° North: December 9 to January 2
- 69° North: December 1 to January 10
- 70° North: November 26 to January 16
- 71° North: November 21 to January 21
- 72° North: November 16 to January 25
Where To See The Polar Twilight
The northernmost settlement in the United States is at Point Barrow called Utqiaġvik (formerly Barrow). Its latitude is at 71°23′ North and so one can see the Polar Civil Twilight there. The Civil Twilight lasts from around November 21 to January 21.
- Utqiaġvik: Northernmost US Settlement At 71°23′ North
Fairbanks is the northernmost larger city in Alaska and the last city that is easily accessible by road. It is located at 64°50′37″ North - that is a tiny bit below the 66.5° North required to see the Polar twilight. So the sun will still pop up a little for a short period of time in the depth of winter. It is close but not quite close enough.
- Fairbanks: The Northernmost "Big City" in The USA At 64°50′37″ North
This means that if one wants to see the polar night, then one needs to go further north in Alaska. In short, the only place in the United States where the polar twilight occurs is in the extreme far north of Alaska where there are only remote and isolated settlements.
If one drives north of Fairbanks past Coldfoot (population 34) on can see the twilight (Coldfoot is at 67°15′5″ North).
A much easier place to see the polar twilight is Nordkapp at the northernmost point of Norway. This is easily accessible, there is accommodation, an airport, and easy road access. Nordkapp is located at 70°58′41″ North. If one is planning to visit Norway, plan on visiting Nordkapp - it is a stunning location at land's end.
Other places are in the extreme north in Canada, Greenland, and Russia.