Equator
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World map showing the equator in red |
The
equator is an imaginary
circle drawn around a
planet (or other
astronomical object) at a distance halfway between the
poles. The equator divides the planet into a
Northern Hemisphere and a
Southern Hemisphere. The
latitude of the equator is, by definition, 0°. The length of
Earth's equator is about 40,075.0
km, or 24,901.5
miles.
The equator is one of the five main
circles of latitude based on the relationship of the Earth's
rotation and plane of
orbit around the sun. Additionally, the equator is the only line of latitude which is also a
great circle.
The
Sun, in its
seasonal movement through the sky, passes directly over the equator twice each
year on the
March and
September Equinoxes. At the equator, the rays of the sun are
perpendicular to the surface of the earth on these dates.
Places near the equator experience the quickest rates of
sunrise and
sunset in the world, taking minutes. Such places also have a relatively constant amount of day/night time on every day throughout the year compared with more northerly or southerly places.
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In tourist areas, the equator is often marked on the sides of roads |
Also, in relation to launching of
satellites, the closeness of the launch centre requires the thrust to be comparatively lesser, and as one moves away from the equator, one has to ensure that the
payload in the launch vehicle is not much, for to get into the right
orbit, more
thrust is required.
In many
tropical regions people identify 2
seasons, wet and dry, but most places very close to the equator are wet throughout the year, although seasons can vary depending on a variety of factors including elevation and proximity to an
ocean.
The surface of the Earth at the equator is mainly
ocean.
The highest point on the Equator is 4,690 m, at
77°59′31" W on the south slopes of
Volcán Cayambe (summit 5,790 m) in
Ecuador. This is a short distance above the
snow line, and is the only point on the Equator where
snow lies on the ground (
Google Earth satellite data and photos).
The equator traverses the land and/or water of 13
countries in total:
*
São Tomé and Príncipe - passing through
Ilhéu das Rolas, an
islet in this archipelago
*
Gabon*
Republic of the Congo*
Democratic Republic of Congo*
Uganda - including some islets in
Lake Victoria*
Kenya*
Somalia*
Maldives - misses every
island, passing between
Gaafu Dhaalu Atoll and
Gnaviyani Atoll*
Indonesia - crosses many islands, most notably
Sumatra,
Borneo,
Sulawesi, and
Halmahera*
Kiribati - misses every island, passing between
Aranuka and
Nonouti Atolls in the
Gilbert Islands*
Ecuador - including
Isabela Island in the
Galápagos Islands*
Colombia*
Brazil - including some islands in the mouth of the
Amazon River and passing through
Macapá, capital of
Amapá state
The equator narrowly misses the territory of the
United States near
Baker Island and
Jarvis Island in the
United States Minor Outlying Islands. The southern end of Baker Island lies just 13 minutes of latitude north of the equator, putting the equator just outside the 12-mile limit for territorial waters. However, the equator does pass through the
Contiguous Waters and the
Exclusive Economic Zone of the United States.
Contrary to its name, no part of
Equatorial Guinea lies on the equator.
Seafaring tradition maintains that all sailors who cross the equator during a nautical voyage must undergo rites of passage and elaborate rituals initiating them into The Solemn Mysteries of the Ancient Order of the Deep. These rituals date back to the Middle Ages, though the current ceremonies are most likely derived from
Viking traditions. Those who have never "crossed the line" are derisively referred to as "pollywogs" or simply "slimy wogs". Upon entering the domain of His Royal Majesty, Neptunus Rex, all wogs are subject to various initiation rituals performed by those members of the crew who have made the journey before. Upon completion of the initiation ceremony, the wogs are then known as "trusty Shellbacks". If the crossing of the equator is done at the
180th meridian, the title of "Golden Shellback" is conferred, recognizing the simultaneous entry into the realm of the Golden Dragon. If the crossing occurs at the Greenwich or
Prime Meridian, the sailor is considered to be an "Emerald Shellback".
*
Thermal equator*
Intertropical Convergence Zone*
Prime Meridian
