An annular

solar eclipse A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring the view of the Sun from a small part of Earth, totally or partially. Such an alignment occurs approximately every six months, during the eclipse season i ...

occurred at the Moon's

ascending node An orbital node is either of the two points where an orbit intersects a plane of reference to which it is inclined. A non-inclined orbit, which is contained in the reference plane, has no nodes. Planes of reference Common planes of referenc ...

of orbit on Wednesday, December 14, 1955, with a

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

of 0.9176. A solar eclipse occurs when the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

passes between

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

and the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's

apparent diameter The angular diameter, angular size, apparent diameter, or apparent size is an angular separation (in units of angle) describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the '' visual ...

is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an

annulus Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to: Human anatomy * ''Anulus fibrosus disci intervertebralis'', spinal structure * Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus comm ...

(ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring about 1 day before

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

(on December 15, 1955, at 7:10 UTC), the Moon's apparent diameter was smaller. The duration of annularity at maximum eclipse (closest to but slightly shorter than the longest duration) was 12 minutes, 9.17 seconds in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

. It was the longest annular solar eclipse from December 17, 168 to January 14, 3080. Among all the 23740 solar eclipses from 4000 BC to 6000 AD, 7881 are annular, and only 3 of them are longer than this one. This was the 20th member of Solar Saros 141, and the last of first set of solar eclipses without a penumbral internal contact (without a penumbra northern limit), the next event is the December 24, 1973 event, which is the first of 19 solar eclipses with a penumbral internal contact (has penumbral northern and southern limits) until 2298 Jul 09. Annularity was visible from

French Equatorial Africa French Equatorial Africa (, or AEF) was a federation of French colonial territories in Equatorial Africa which consisted of Gabon, French Congo, Ubangi-Shari, and Chad. It existed from 1910 to 1958 and its administration was based in Brazzav ...

(the part now belonging to

Chad Chad, officially the Republic of Chad, is a landlocked country at the crossroads of North Africa, North and Central Africa. It is bordered by Libya to Chad–Libya border, the north, Sudan to Chad–Sudan border, the east, the Central Afric ...

Libya Libya, officially the State of Libya, is a country in the Maghreb region of North Africa. It borders the Mediterranean Sea to the north, Egypt to Egypt–Libya border, the east, Sudan to Libya–Sudan border, the southeast, Chad to Chad–L ...

Anglo-Egyptian Sudan Anglo-Egyptian Sudan ( ') was a condominium (international law), condominium of the United Kingdom and Kingdom of Egypt, Egypt between 1899 and 1956, corresponding mostly to the territory of present-day South Sudan and Sudan. Legally, sovereig ...

(the part now belonging to

Sudan Sudan, officially the Republic of the Sudan, is a country in Northeast Africa. It borders the Central African Republic to the southwest, Chad to the west, Libya to the northwest, Egypt to the north, the Red Sea to the east, Eritrea and Ethiopi ...

) including the capital city

Khartoum Khartoum or Khartum is the capital city of Sudan as well as Khartoum State. With an estimated population of 7.1 million people, Greater Khartoum is the largest urban area in Sudan. Khartoum is located at the confluence of the White Nile – flo ...

French Somaliland French Somaliland (; ; ) was a French colony in the Horn of Africa. It existed between 1884 and 1967, at which became the French Territory of the Afars and the Issas. The Republic of Djibouti is its legal successor state. History French Somalil ...

(today's

Djibouti Djibouti, officially the Republic of Djibouti, is a country in the Horn of Africa, bordered by Somalia to the south, Ethiopia to the southwest, Eritrea in the north, and the Red Sea and the Gulf of Aden to the east. The country has an area ...

) including the capital

Djibouti City Djibouti (also called Djibouti City and Jibuti in early Western texts) is the capital city of the Djibouti, Republic of Djibouti. It is located in the coastal Djibouti Region on the Gulf of Tadjoura. Djibouti has a population of around 780,000 ...

British Somaliland British Somaliland, officially the Somaliland Protectorate (), was a protectorate of the United Kingdom in modern Somaliland. It was bordered by Italian Somalia, French Somali Coast and Ethiopian Empire, Abyssinia (Italian Ethiopia from 1936 ...

(today's

Somaliland Somaliland, officially the Republic of Somaliland, is an List of states with limited recognition, unrecognised country in the Horn of Africa. It is located in the southern coast of the Gulf of Aden and bordered by Djibouti to the northwest, E ...

) including the capital city

Hargeisa Hargeisa ( ; ; ) is the capital and largest city of the Republic of Somaliland, a ''List of states with limited recognition, de facto'' sovereign state in the Horn of Africa, still considered internationally to be part of Somalia. It is also th ...

, the

Trust Territory of Somaliland The Trust Territory of Somaliland, officially the Trust Territory of Somaliland under Italian Administration (), was a United Nations Trust Territory from 1950 to 1960, following the dissolution of the former British Military Administration. I ...

(today's

Somalia Somalia, officially the Federal Republic of Somalia, is the easternmost country in continental Africa. The country is located in the Horn of Africa and is bordered by Ethiopia to the west, Djibouti to the northwest, Kenya to the southwest, th ...

), the

Maldives The Maldives, officially the Republic of Maldives, and historically known as the Maldive Islands, is an Archipelagic state, archipelagic country in South Asia located in the Indian Ocean. The Maldives is southwest of Sri Lanka and India, abou ...

Andaman and Nicobar Islands The Andaman and Nicobar Islands is a union territory of India comprising 572 islands, of which only 38 are inhabited. The islands are grouped into two main clusters: the northern Andaman Islands and the southern Nicobar Islands, separated by a ...

Burma Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and ha ...

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

including the capital city

Bangkok Bangkok, officially known in Thai language, Thai as Krung Thep Maha Nakhon and colloquially as Krung Thep, is the capital and most populous city of Thailand. The city occupies in the Chao Phraya River delta in central Thailand and has an estim ...

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

Laos Laos, officially the Lao People's Democratic Republic (LPDR), is the only landlocked country in Southeast Asia. It is bordered by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the southeast, and Thailand to the west and ...

North Vietnam North Vietnam, officially the Democratic Republic of Vietnam (DRV; ; VNDCCH), was a country in Southeast Asia from 1945 to 1976, with sovereignty fully recognized in 1954 Geneva Conference, 1954. A member of the communist Eastern Bloc, it o ...

and

South Vietnam South Vietnam, officially the Republic of Vietnam (RVN; , VNCH), was a country in Southeast Asia that existed from 1955 to 1975. It first garnered Diplomatic recognition, international recognition in 1949 as the State of Vietnam within the ...

(now belonging to

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

British Hong Kong Hong Kong was under British Empire, British rule from 1841 to 1997, except for a Japanese occupation of Hong Kong, brief period of Japanese occupation during World War II from 1941 to 1945. It was a crown colony of the United Kingdom from 1841 ...

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

(including the

Pratas Island Pratas Island,, United States National Geospatial-Intelligence Agency also known as the Tungsha Islands or the Dongsha Islands (), is a coral island situated in the northern part of the South China Sea administered as part of Cijin District, K ...

s), and

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi Islands, Ōsumi, Tokara Islands, Tokara and A ...

. A partial eclipse was visible for parts of

East Africa East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the regi ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. This was the third of four central solar eclipses visible from Bangkok from

1948 Events January * January 1 ** The General Agreement on Tariffs and Trade (GATT) is inaugurated. ** The current Constitutions of Constitution of Italy, Italy and of Constitution of New Jersey, New Jersey (both later subject to amendment) ...

1958 Events January * January 1 – The European Economic Community (EEC) comes into being. * January 3 – The West Indies Federation is formed. * January 4 ** Edmund Hillary's Commonwealth Trans-Antarctic Expedition completes the thir ...

, where it is extremely rare for a large city to witness four central solar eclipses within 10 years.

Extreme duration

With a maximum length of annularity duration of 12 minutes and 9.17 seconds, this is the longest solar eclipse in the millennium, as well as the longest duration in Saros 141 and one of the longest eclipses ever observed. The annular path begins in northern

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

, then passing

(near the maximum eclipse), then crosses just southern edge of

Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

, then the track continues to some countries in

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

and the track ends just slightly after the track passes

Observation

A joint team of the

Georgetown University Astronomical Observatory The Georgetown University Astronomical Observatory (also the Heyden Observatory and Francis J. Heyden Observatory) was founded in 1841 by Father James Curley of the Department of Physics at Georgetown College. Father Curley chose a site on the c ...

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

and the

United States Air Force The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...

observed the annular eclipse in multiple locations around the world. Among them, in Khartoum, capital of Anglo-Egyptian Sudan, the partial phase started before sunrise, and the annular phase was shortly after sunrise. The team measured the refraction with the

zenith distance The zenith (, ) is the imaginary point on the celestial sphere directly "above" a particular location. "Above" means in the vertical direction (plumb line) opposite to the gravity direction at that location (nadir). The zenith is the "highest" p ...

between 80° and 90°.

Eclipse details

Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.

Eclipse season

This eclipse is part of an

eclipse season An eclipse season is a period, roughly every six months, when eclipses occur. Eclipse seasons are the result of the axial parallelism of the Orbit of the Moon, Moon's orbital plane (orbital inclination, tilted five degrees to the ecliptic, Earth ...

, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a

fortnight A fortnight is a unit of time equal to 14 days (two weeks). The word derives from the Old English term , meaning "" (or "fourteen days", since the Anglo-Saxons counted by nights). Astronomy and tides In astronomy, a ''lunar fortnight'' is hal ...

Related eclipses

Eclipses in 1955

* A penumbral lunar eclipse on January 8. * A penumbral lunar eclipse on June 5. * A total solar eclipse on June 20. * A partial lunar eclipse on November 29. * An annular solar eclipse on December 14.

Metonic

* Preceded by: Solar eclipse of February 25, 1952 * Followed by:

Solar eclipse of October 2, 1959 A total solar eclipse occurred at the Moon's ascending node of orbit on Friday, October 2, 1959, with a magnitude of 1.0325. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of th ...

Tzolkinex

* Preceded by:

Solar eclipse of November 1, 1948 A total solar eclipse occurred at the Moon's descending node of orbit on Monday, November 1, 1948, with a magnitude of 1.0231. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of ...

* Followed by:

Solar eclipse of January 25, 1963 An annular solar eclipse occurred at the Moon's descending node of orbit on Friday, January 25, 1963, with a magnitude of 0.9951. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image ...

Half-Saros

* Preceded by: Lunar eclipse of December 8, 1946 * Followed by: Lunar eclipse of December 19, 1964

Tritos

* Preceded by:

Solar eclipse of January 14, 1945 An annular solar eclipse occurred at the Moon's descending node of orbit on Sunday, January 14, 1945, with a magnitude of 0.997. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image o ...

* Followed by:

Solar eclipse of November 12, 1966 A total solar eclipse occurred at the Moon's descending node of orbit on Saturday, November 12, 1966, with a magnitude of 1.0234. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image ...

Solar Saros 141

* Preceded by: Solar eclipse of December 2, 1937 * Followed by: Solar eclipse of December 24, 1973

Inex

* Preceded by: Solar eclipse of January 3, 1927 * Followed by:

Solar eclipse of November 22, 1984 A total solar eclipse occurred at the Moon's descending node of orbit between Thursday, November 22 and Friday, November 23, 1984, with a magnitude of 1.0237. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally o ...

Triad

* Preceded by:

Solar eclipse of February 11, 1869 Solar may refer to: Astronomy * Of or relating to the Sun ** Solar telescope, a special purpose telescope used to observe the Sun ** A device that utilizes solar energy (e.g. "solar panels") ** Solar calendar, a calendar whose dates indicate t ...

* Followed by:

Solar eclipse of October 14, 2042 An annular solar eclipse will occur at the Moon's descending node of orbit on Tuesday, October 14, 2042, with a magnitude of 0.93. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image ...

Solar eclipses of 1953–1956

Saros 141

Metonic series

Tritos series

Inex series

Notes

References

{{Solar eclipses 1955 12 14 1955 in science 1955 12 14 December 1955