![]() ![]() You can experience a polar twilight anywhere within the Arctic Circle at any point between the autumnal equinox (towards the end of September) and the vernal equinox (towards the end of March). Where can you experience the polar night? On these days, the dimmest stars visible to the naked eye will be visible at midday on a clear day. This is when the sun is 12 to 18 degrees below the horizon and, basically, illumination comes only from the stars.Īstronomical polar night occurs when there is no astronomical twilight. The next one up is nautical polar night, when there is only astronomical twilight. This is when the sun is below the horizon but by less than 6 degrees – known as civil twilight.Ībove this we have civil polar night, where there is no civil twilight, only nautical twilight, where the sun is between 6 and 12 degrees below the horizon. Polar twilight occurs at the inner borders of the polar circles. Where you are within the Arctic Circle will dictate which type(s) of polar night you will get and for how long. But as no one actually lives at the South Pole, this isn’t all that interesting to very many people! Types of polar night What this means is that the South Pole actually gets polar nights for one week longer than the North Pole. This is also what causes us to have seasons, equinoxes and solstices.Īnother factor is that the Earth’s orbit around the sun is elliptical. This means that there’s an area at the top and the bottom that gets 6 months of day followed by 6 months of night. Instead, the Earth is tilted by approximately 23.5 degrees. If the Earth rotated exactly perpendicular to its axis then we would all have 12 hour days and 12 hour nights no matter where we were. In fact, the Arctic Circle ‘marks the northernmost point at which the centre of the noon sun is just visible on the December solstice and the southernmost point at which the centre of the midnight sun is just visible on the June solstice’.ĭepending where you are within the Arctic Circle, polar nights will last from one day to six months! What causes the polar nights? Polar nights occur between the Autumnal and Spring Equinoxes inside the Arctic Circle. Where can you experience the polar night?. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |