The midnight sun is a natural phenomenon that is observed in latitudes north of the Arctic Circle and south of the Antarctic Circle. During summer days, the Sun is visible for 24 hours or longer in these regions, provided the weather conditions are fair. This amazing natural phenomenon occurs in the Northern Hemisphere at the summer solstice, i.e., on June 21. But, in the Southern Hemisphere, it occurs at the winter solstice, i.e., on December 22. Solstice refers to the period when the Sun is at its greatest distance from the celestial equator. The midnight sun phenomenon, where the Sun does not set for 24 hours or more, occurs only in the polar regions. This phenomenon can be explained with the help of the axial tilt of the Earth. The Earth is tilted at an angle when it revolves around the Sun, which is known as axial tilt. This tilt is 23 degrees 26 minutes or approximately, 23.5 degrees. In other words, the Earth's rotational axis is tilted at an angle of 23.5 degrees with respect to a line perpendicular to the ecliptic. Ecliptic is the orbital plane, or the plane on which the Earth orbits the Sun. The axial tilt remains constant as the Earth revolves around the Sun and is responsible for the phenomenon known as midnight sun. As a result of this tilt, the Northern Hemisphere becomes inclined towards the Sun in such a way that it receives sunlight continuously for more than 24 hours at the summer solstice. In the same way, the Southern Hemisphere is tilted towards the Sun for six months at the winter solstice, and hence, experiences the midnight sun. The duration of this phenomenon depends on how far an area is from the Arctic and Antarctic Circles. Places which are located north of the Arctic Circle and south of the Antarctic Circle can receive sunlight continuously for more than one day during the year. The North Pole and the South Pole can have midnight sun for continuously six months in a year, which is also known as polar day. On the other hand, midnight sun can be visible for just one day during each year in the areas near the polar circles. White nights are a related phenomenon to midnight sun and can be observed in places above 60° 34' latitude. These places are located south of the Arctic Circle and north of the Atlantic Circle. Instead of midnight sun, these places experience late sunsets, early sunrise, and midnight twilight. The Sun does set in these areas, but does not dip far below the horizon, for which the nights are not completely dark. In fact, it is possible to carry out daytime activities, like reading without the need for artificial light. The term used for this phenomenon is white nights, and this period of the year is celebrated in many cities with cultural events. The White Nights Festival celebrated in Saint Petersburg, Russia is especially famous throughout the world. Norway is considered one of the best places to observe the amazing phenomenon of midnight sun. North Cape in Norway, which is the northernmost point of Europe, is known to have midnight sun for about 76 days from May 14 to July 30. Other places of Norway, where you can see this extraordinary natural phenomenon are Longyearbyen (Spitsbergen), Hammerfest, Tromso, Hausberg, and Narvik. In Hammerfest, the ideal time to view the midnight sun is from May 16 to July 27, while April 20 to August 20 is the best time to go to Longyearbyen for this purpose. In Tromso and Narvik, the midnight sun is visible from May 20 to July 22, and May 25 to July 18, respectively. Apart from Norway, Greenland, Northern Iceland, Finland, Northern Sweden, Canada, and Fairbanks, Alaska (USA) are some other good places to see the phenomenon. The midnight sun can create difficulty in getting enough sleep during the night. This problem is commonly faced by the visitors, who come to these places during this period. The local residents also get affected, though to a lesser extent. Midnight sun is also believed to be associated with hypomania, which is a milder form of mania, characterized by persistent excitement, unusual exhilaration, or an irritable mood. For Jewish people, midnight sun is responsible for the development of a new set of Jewish rules, specifically for the polar regions. The Jewish religious rites are based around the cycle of day and night, and therefore, it becomes really difficult to follow them in the polar regions. The followers of Islam also face some unique challenges in these regions. During Ramadan, the Muslims fast during the daytime, and end it at sunset. As the sun continues to shine for more than 24 hours in the polar regions, fasting during Ramadan could imply a total abstinence from food. As a result, fasting time is often modified according to the time of Mecca or Medina, or a place nearest to that area. The 5 obligatory prayers of the Muslims are also timed according to the position of the Sun. In the polar regions, Muslims can offer these prayers as per the timing of Mecca or a nearby place having normal day and night cycle. Despite the difficulties associated with the midnight sun phenomenon, it holds a special attraction for the tourists. Tourists across the world rush to those few cities, where the Sun simply refuses to set, thus offering an unusual experience of a lifetime.