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John Caister Bennett
John Caister "Jack" Bennett (born 6 April 1914 in Estcourt, Natal, died 30 May 1990 in Pretoria), was a South African civil servant and amateur astronomer. His mother was British and his father was from Tasmania. He attended school in Ficksburg and began to work in public service after graduating in 1934, initially in the forestry administration in Elgin before moving to the administration of Transvaal Province in Pretoria. During World War II he served as a soldier in South Africa, Egypt and Italy. In 1974 he retired from the public service. From 1985 he began to suffer from arthritis and soon afterwards his health deteriorated so much that he had to sell his house in Pretoria's Riviera neighborhood and move into a nursing home. He died on 30 May 1990 at the age of 76. Amateur astronomer Bennett's interest in astronomy began early when his mother showed him the starry sky with the Southern Cross and the planets on the way home from evening church visits and told him about her ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
6 April
Events Pre–1600 *46 BC – Julius Caesar defeats Caecilius Metellus Scipio and Marcus Porcius Cato (Cato the Younger) at the Battle of Thapsus. * 402 – Stilicho defeats the Visigoths under Alaric in the Battle of Pollentia. *1320 – The Scots reaffirm their independence by signing the Declaration of Arbroath. *1453 – Mehmed II begins his siege of Constantinople. The city falls on May 29 and is renamed Istanbul. *1580 – One of the largest earthquakes recorded in the history of England, Flanders, or Northern France, takes place. 1601–1900 *1652 – At the Cape of Good Hope, Dutch sailor Jan van Riebeeck establishes a resupply camp that eventually becomes Cape Town. *1712 – The New York Slave Revolt of 1712 begins near Broadway. *1776 – American Revolutionary War: Ships of the Continental Navy fail in their attempt to capture a Royal Navy dispatch boat. *1782 – King Buddha Yodfa Chulaloke (Rama I) of Siam (modern day Thail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Satellite
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scientific research, and Earth observation. Additional military uses are reconnaissance, early warning, signals intelligence and, potentially, weapon delivery. Other satellites include the final rocket stages that place satellites in orbit and formerly useful satellites that later become defunct. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which are small CubeSats. Similar satellites can work together as groups, forming constellations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C/1974 V2
Comet Bennett, formally designated as C/1974 V2, is a non-periodic comet that was seen in 1974. During its most recent perihelion, the comet was observed to split apart and disintegrate. Discovery and observations On the morning of 13 November 1974, John Caister Bennett discovered his second comet as a diffuse 9th-magnitude object in the constellation Hydra using a refractor from Pretoria, South Africa. He had spent a total of 482 hours searching for a new comet since his first discovery in 1969. At the time, the comet had no discernible coma nor tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ..., however Bennett was of the opinion it experienced an outburst lasting about five days just before discovery References Notes Citations External links * Non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C/1969 Y1
Comet Bennett, formally known as C/1969 Y1 (old style 1970 II and 1969i), was one of the two bright comets observed in the 1970s, along with Comet West and is considered a great comet. The name is also borne by an altogether different comet, C/1974 V2. Discovered by John Caister Bennett on December 28, 1969, while still almost two AUs from the Sun, it reached perihelion on March 20, passing closest to Earth on 26 March 1970, as it receded, peaking at magnitude 0. It was last observed on 27 February 1971. Observational history The comet was discovered by John Caister Bennett on 28 December 1969 from Pretoria, South Africa, during his comet seeking routine. The comet was located in the constellation Tucana, in 65° south declination, and had an estimated magnitude of 8.5. At that time the comet was about 1.7 AU both from the Sun and the Earth. The orbit was computed by M. P. Candy of the Perth Observatory and it became apparent that the comet could become a bright object by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of South Africa
The University of South Africa (UNISA) is the largest university system in South Africa by enrollment. It attracts a third of all higher education students in South Africa. Through various colleges and affiliates, UNISA has over 400,000 students, including international students from 130 countries worldwide, making it one of the world's mega universities and the only such university in Africa. As a comprehensive university, Unisa offers both vocational and academic programmes, many of which have received international accreditation. It also has an extensive geographical footprint, providing its students with recognition and employability in many countries around the world. The university lists many notable South Africans among its alumni, including two Nobel Prize winners: Nelson Mandela, the first democratically elected president of South Africa, and Archbishop Desmond Tutu. Founded in 1873 as the University of the Cape of Good Hope, the University of South Africa (comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C/1974 V2 (Bennett)
Comet Bennett, formally designated as C/1974 V2, is a non-periodic comet that was seen in 1974. During its most recent perihelion, the comet was observed to split apart and disintegrate. Discovery and observations On the morning of 13 November 1974, John Caister Bennett discovered his second comet as a diffuse 9th-magnitude object in the constellation Hydra using a refractor from Pretoria, South Africa. He had spent a total of 482 hours searching for a new comet since his first discovery in 1969. At the time, the comet had no discernible coma nor tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ..., however Bennett was of the opinion it experienced an outburst lasting about five days just before discovery References Notes Citations External links * Non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C/1969 Y1 (Bennett)
Comet Bennett, formally known as C/1969 Y1 (old style 1970 II and 1969i), was one of the two bright comets observed in the 1970s, along with Comet West and is considered a great comet. The name is also borne by an altogether different comet, C/1974 V2. Discovered by John Caister Bennett on December 28, 1969, while still almost two AUs from the Sun, it reached perihelion on March 20, passing closest to Earth on 26 March 1970, as it receded, peaking at magnitude 0. It was last observed on 27 February 1971. Observational history The comet was discovered by John Caister Bennett on 28 December 1969 from Pretoria, South Africa, during his comet seeking routine. The comet was located in the constellation Tucana, in 65° south declination, and had an estimated magnitude of 8.5. At that time the comet was about 1.7 AU both from the Sun and the Earth. The orbit was computed by M. P. Candy of the Perth Observatory and it became apparent that the comet could become a bright object by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernova
A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed to form a diffuse nebula. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. The last supernova directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not long after Tycho's Supernova in 1572, both of which were visible to the naked eye. The supernova remnant, remnants of more recent supernovae have been found, and observations of supernovae in other galaxies suggest they occur in the Milky Way on average about three times every century. A supernova in the Milky Way would almost certainly be observable through mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydra (constellation)
Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees, and also the longest at over 100 degrees. Its southern end borders Libra (constellation), Libra and Centaurus (constellation), Centaurus and its northern end borders Cancer (constellation), Cancer. It was included among the 48 constellations listed by the 2nd century astronomer Ptolemy. Commonly represented as a water snake (other), water snake, it straddles the celestial equator. History and mythology Western mythology The Greek constellation of Hydra is an adaptation of a Babylonian astronomy, Babylonian constellation: the MUL.APIN includes a "serpent" constellation (MUL.DINGIR.MUŠ) that loosely corresponds to Hydra. It is one of two Babylonian "serpent" constellations (the other being the origin of the Greek Serpens), a mythological hybrid of serpent, lion and bird. The shape of Hydra resembles a twisting snake, and features as such in some Greek myths. One myth associates it w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 83
Messier 83 or M83, also known as the Southern Pinwheel Galaxy and NGC 5236, is a barred spiral galaxy approximately 15 million light-years away in the constellation borders of Hydra (constellation), Hydra and Centaurus. Nicolas-Louis de Lacaille discovered M83 on 17 February 1752 at the Cape of Good Hope. Charles Messier added it to his catalogue of nebulous objects (now known as the Messier object, Messier Catalogue) in March 1781. It is one of the closest and brightest barred spiral galaxies in the sky, and is visible with binoculars. It has an Galaxy#Isophotal diameter, isophotal diameter at about . Its nickname of the Southern Pinwheel derives from its resemblance to the Pinwheel Galaxy (M101). Characteristics M83 is a massive, grand design spiral galaxy. Its Galaxy morphological classification, morphological classification in the De Vaucouleurs system is SAB(s)c, where the 'SAB' denotes a weak-barred spiral, '(s)' indicates a pure spiral structure with no ring, and 'c' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier Catalog
The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ' (''Catalogue of Nebulae and Star Clusters''). Because Messier was interested only in finding comets, he created a list of those non-comet objects that frustrated his hunt for them. This list, which Messier created in collaboration with his assistant Pierre Méchain, is now known as the ''Messier catalogue''. The Messier catalogue is one of the most famous lists of astronomical objects, and many objects on the list are still referenced by their Messier numbers. The catalogue includes most of the astronomical deep-sky objects that can be easily observed from Earth's Northern Hemisphere; many Messier objects are popular targets for amateur astronomers. A preliminary version of the catalogue first appeared in 1774 in the ''Memoirs'' of the French Academy of Sciences for the year 1771. The first version of Messier's catalogue contained 45 objects, which wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet
A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding the nucleus, and sometimes a Comet tail, tail of gas and dust gas blown out from the coma. These phenomena are due to the effects of solar radiation and the outstreaming solar wind plasma acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently close and bright, a comet may be seen from Earth without the aid of a telescope and can Subtended angle, subtend an arc of up to 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
