# Polar Day/Night

This is my first question so any feedback is appreciated! I basically have an Earth analog that has an axial tilt of approximately 12 degrees instead of Earth's 23, and I wanted to find out how I could approximate the length of the longer polar nights the flora and fauna would be subjected too. Thanks!

Edit: I would also like to know how I could approximate how much of the planet would be affected by this polar night, as in what latitude to the pole would the polar night cover.

• Axial tilt doesn't matter. The longest polar night will still be half a year, as will the longest polar day. Those happen only exactly at the poles, though. The length of the longest polar day or night decreases from the pole to the polar circle (at 78 degrees latitude in your story), where there is exactly one day (at the summer solstice) and, half a year later, one night (at the winter solstice) longer than a full solar day. Jun 28 '18 at 3:42
• @AlexP you could elaborate that into an answer. Jun 28 '18 at 3:56
• @Renan: OK done. Jun 28 '18 at 4:40

The relationship between the axial tilt angle $\theta$ and the latitude of the polar circle, $90^{\circ} - \theta$. The planet is shown at the summer solstice. Own work, available on Flickr under the CC BY-2.0 license.