Earth orbits the Sun Photo by Wikipedia
In this blog post, I will share how Earth orbits the Sun and interesting facts about Sun and Earth. I explored and realized why some Nordic countries (For example: Finland, Sweden and Norway) have Polar Night in Winter and Midnight Sun in Summer.
Polar Night: Polar Night is an extended period of nighttime that lasts 24 hours or more. In the other words, the Sun never rises over a period of 24 consecutive hours. So, that means we will not see Sunlight during this time in northernmost and southernmost regions of Earth. For example, In Norway, Polar Night generally begins on November and lasts until January.
Midnight Sun: Midnight is an extended period of daytime that lasts 24 hours or more. In the other words, the Sun does not set over a period of 24 consecutive hours in northernmost and southernmost regions of Earth. It’s opposite of Polar Night. For example, In Svalbard, Norway, Midnight Sun generally occurs between April and August.
Why does Polar Night occur?
Credit to: Polar Guidebook for photo
Firstly, we need to understand how Earth orbits the Sun. The Earth orbits around the Sun that takes 940 million km and 365.25 days or we call that’s one year and Earth also rotating on it’s own axis.
So, why does Earth orbit around the Sun?
Earth orbits around the Sun because the amount of gravity exerted by the Sun is much more than the Earth’s gravitational pull, the Earth is forced into an orbit around the sun.
The Earth rotates on a tilted axis of around 23.5 degrees. See in above photo. Polar Night refers to an extended period of nighttime that lasts 24 hours or more. In Winter, Arctic Circle region has no sunlight because of Earth’s position and is tilted on it’s axis by 23.5 degrees. So, that occurs 24 hours darkness in countries such as Finland, Sweden Norway and etc…
Why does Midnight Sun or Polar Day occur?
Credit to: offthemap for photo
If you now understand about Polar Night, Midnight Sun is opposite of Polar Night. Midnight Sun refers to an extended period of daytime that lasts 24 hours or more.
In Summer, the North Pole stays in full sunlight 24 hours also known as Sun never sets in Arctic Circle region because of Earth’s position and rotates on a tilted axis of around 23.5 degrees. See in above photo. So, that occurs Midnight Sun also know as Polar Day during the Summer in Arctic Circle region. In the other hand, Anterctic Circle has no Sunlight during this time.
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