- On what date and in what season does it begin?
- Why is it called that?
- Countries across the Tropic of Cancer
- What is it for?
- Seasons of the year in the tropics
- References
The Tropic of Cancer is at latitude 23.43694 °, north of the Earth's equator. It is also known as the North Tropic, and it is the highest circle of latitude on the planet where the Sun can be located directly on Earth. That is, a person located at this latitude can have the Sun directly overhead, from their perspective.
Any latitude above this would not allow the occurrence of such a phenomenon, since the planet's axis of rotation prevents the necessary angle from occurring. This phenomenon only occurs once a year, during the June solstice. Right now the northern hemisphere of the Earth is tilted as far towards the Sun as possible.
During the solstice process, the Sun is in the constellation Gemini. However, several centuries ago the June solstice showed the Sun in the constellation Cancer, which originally gave the name to the North Tropic. This tropic is one of the lines through which the planet is divided for the proper calculation of different measurements.
Given the humidity of this area, it is in the Tropic of Cancer where the largest tropical forests in the world are found. The area covered by this tropic is quite wide, since it crosses 16 different countries located on 3 continents, in addition to 6 bodies of water.
On what date and in what season does it begin?
The solar phenomenon of the Tropic of Cancer usually occurs on June 22 of each year. At this time, the position of the Earth in relation to the Sun causes the light of the star to be received in full throughout the northern tropics.
This occurs due to the translational movement of the planet: the same fact that makes the years and seasons exist on Earth in turn causes two solstices: one in summer and the other in winter.
A solstice occurs when the sun reaches its maximum height from the terrestrial point of view, in relation to the equator and the celestial sphere.
The seasons of the planet are directly related to these events and to the equinoxes (when, twice a year, the Sun is located directly on the equator).
The summer solstice occurs in the northern tropics, while the winter solstice occurs in the southern hemisphere of the Earth, in the tropic of Capricorn. The phenomenon is the same in both tropics, but it occurs at different times of the year.
Although the position of the tropics can vary slightly over time, it usually occurs around this same date.
Why is it called that?
When this tropic was named, humanity did not have extensive knowledge about the functioning of the universe, planets and stars.
There was a belief that the solar system revolved around the Earth. The solstices, equinoxes and phenomena related to the Sun occurred in the same way, but there was another perspective on these.
2000 years ago, when the tropics were first named, the Sun occupied the place of the constellation Cancer in the sky.
The movement of the solar system and the rest of the stars in relation to the center of the Milky Way (the galaxy where the Earth is located) have caused slow but incessant movements in the location of the stars in the terrestrial sky, bringing with it phenomena such as the change of location of the Sun in the constellations.
Today, the Sun is located within the constellation Gemini, but the name of the Tropic of Cancer does not change. Interestingly, the Sun will relocate the position of the constellation Cancer in approximately 24,000 years.
Countries across the Tropic of Cancer
The position of the tropics is not fixed. Every year, the tropics relocate 15 meters to the south of the planet.
The movement that causes this effect is constant and never stops; it is related to the movement of the earth's rotational axes and to the other circles of latitude. The Tropic of Capricorn is also moving at the same speed, but in a northerly direction.
Starting from the prime meridian, the Tropic of Cancer passes through 16 countries and other territories, which are:
- Algeria
- Niger
- Libya
- Egypt
- Red Sea
- Saudi Arabia
- United Arab Emirates
- Oman
- Indian Ocean
- India
- Bangladesh
- Myanmar
- China
- Taiwan
- Philippine Sea
- Pacific Ocean
- Mexico
- Gulf of california
- Bahamas
- Western Sahara (Morocco / Sahrawi Arab Democratic Republic)
- Mauritania
- Mali
The total length of this tropic is approximately 36,788 kilometers, but it is constantly changing.
What is it for?
The Tropic of Cancer defines part of the Earth's tropical zone and its location generally means that the zones and countries that are part of it have a hot and dry climate.
In certain parts of the eastern tropics there are heavy rainfalls. These occur due to the movements of the wind and the way in which they interact with the mountain formations in the area.
In the tropics, the average temperature generally remains above 18 ° C. The reason why there are relatively high amounts of rainfall in these areas is due to the large amount of water that condenses the Sun, which generates abundant rain, especially in the jungles and forests located in the tropics.
A large land area of the Tropic of Capricorn is occupied by the Sahara Desert, while the east generally has a monsoon climate, with strong breezes and rainfall that vary throughout the year.
Glaciers previously existed in the mountains of Taiwan within the tropics, but no glacial zone currently exists in this area. The closest glacier to the Tropic of Cancer is in the Himalayas.
Seasons of the year in the tropics
Regions outside the tropics typically have four seasons, but countries within the tropics generally only have two and rarely have snow at ground level.
The seasons of the countries located within the Tropic of Capricorn are summer and winter. Summer is also known as the dry season and where the highest temperatures of the year are appreciated, while winter is usually humid and with lower temperatures.
References
- Tropic of Cancer, (nd). Taken from brittanica.com
- Circles of Latitude & Longitude - The Equator, The Prime Meridian, The Tropic of Cancer and Capricorn, (nd). decom
- "Tropic of Cancer." The Columbia Encyclopedia, 6th ed… Taken from Encyclopedia.com
- Prime Meridian, Sara May, June 9, 2015. Taken from nasa.gov
- Tropic of Cancer, (nd), 2018. Taken from wikipedia.org
- Solstice, (nd), 2018. Taken from wikipedia.org
- Equinox, (nd), 2018. Taken from wikipedia.org