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42 Isis
Isis, minor planet designation: 42 Isis, is a large main-belt asteroid, measuring 100.2 km in diameter with a stony ( S-type) composition. It was discovered by English astronomer N.R. Pogson on 23 May 1856 at Oxford, and was his first asteroid discovery. The asteroid's name was chosen by Manuel John Johnson, director of the Radcliffe Observatory in Oxford. Although Isis is the name of an Egyptian goddess, the name was chosen in homage to Pogson's astronomer daughter, (Elizabeth) Isis Pogson. In addition, the Isis is the stretch of the River Thames that runs through Oxford. This asteroid is orbiting the Sun with a period of 3.82 years. The light curve inversion technique, when applied to photometric observations of this asteroid, show multiple local irregularities. The overall shape displays little elongation, with a ratio between the major and minor axes equal to 1.1. The measured rotation period for this model is 13.6 hours. The spectrum of 42 Isis reveals the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norman Robert Pogson
Norman Robert Pogson, CIE (23 March 1829 – 23 June 1891) was an English astronomer who worked in India at the Madras observatory. He discovered several minor planets and made observations on comets. He introduced a mathematical scale of stellar magnitudes with the ratio of two successive magnitudes being the fifth root of one hundred (~2.512) and referred to as Pogson's ratio. Youth and education Norman was born in Nottingham, the son of George Owen Pogson, a hosiery manufacturer, lace dealer and commission agent, "with enough income to support an extended family", and his wife, Mary Ann. It was intended that he should follow his father into business, and he was accordingly sent for "commercial education", but he was fascinated by science, and his mother supported and encouraged this interest. His early education was largely informal. He left school at 16, intending to teach mathematics. At the age of eighteen, he calculated with the help of John Russell Hind of the Royal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radcliffe Observatory
Radcliffe Observatory was the astronomical observatory of the University of Oxford from 1773 until 1934, when the Radcliffe Trustees sold it and built a new observatory in Pretoria, South Africa. It is a Grade I listed building. Today, the observatory forms a part of Green Templeton College of the University of Oxford. History The observatory was founded and named after John Radcliffe by the Radcliffe Trustees. It was built on the suggestion of the astronomer Thomas Hornsby, who was occupying the Savilian Chair of Astronomy, following his observation of the notable transit of Venus across the sun's disc in 1769 from a room in the nearby Radcliffe Infirmary. The observatory building commenced to designs by Henry Keene in 1772, and was completed in 1794 to the designs of James Wyatt, with a prominent octagonal tower based on the Tower of the Winds in Athens. Its tower is topped with a statue by John Bacon of Atlas holding up the World. Until 1839, the Savilian Chair of As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discoveries By N
Discoveries may refer to: Music * ''Discoveries'' (Cannonball Adderley album), 1955 * ''Discoveries'' (Josh Nelson album), 2011 * ''Discoveries'' (Northlane album), 2011 Other uses * ''Discoveries'' (film), a 1939 British film * Discoveries (horse), a racehorse * ''Discoveries'' (Robertson Davies), a 2002 book by Robertson Davies * ''Discoveries'' (TV series), a Canadian youth science television series which aired on CBC Television in 1957 * ''Abrams Discoveries'', a series of illustrated non-fiction books published by Harry N. Abrams * ''Discoveries'', a work by William Butler Yeats, written in 1907 * ''Discoveries'', a magazine published by Cedars-Sinai Medical Center See also * Age of Discoveries * Discovery (other) * Explorations (other) Explorations may refer to: *The plural of exploration Exploration refers to the historical practice of discovering remote lands. It is studied by geographers and historians. Two major eras of exploration occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Background Asteroids
Background may refer to: Performing arts and stagecraft * Background actor * Background artist * Background light * Background music * Background story * Background vocals * ''Background'' (play), a 1950 play by Warren Chetham-Strode Recorded works * ''Background'' (1953 film), a British drama * ''Background'' (1973 film), a documentary * ''Background'' (TV series), a Canadian journalistic television series * ''Background'' (Lifetime album), 1992 * ''Background'' (Bassi Maestro album), 2002 Science and engineering * Background extinction rate * Background independence, a condition in theoretical physics * Background noise * Background radiation, the natural radiation that is always present in a location ** Background (astronomy), small amounts of light coming from otherwise dark parts of the sky ** Cosmic background (other) ** Gravitational wave background ** X-ray background * Background process, software that is running but not being displayed * String b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-type Asteroids (SMASS)
L-type asteroids are relatively uncommon asteroids with a strongly reddish spectrum shortwards of 0.75 μm, and a featureless flat spectrum longwards of this. In comparison with the K-type, they exhibit a more reddish spectrum at visible wavelengths and a flat spectrum in the infrared. These asteroids were described as "featureless" S-types in the Tholen classification. The L-type was formally introduced in the SMASS classification, although previous studies had noted the unusual spectra of two of its members 387 Aquitania and 980 Anacostia. There are 41 asteroids classified as L-types in the SMASS taxonomy. Ld-type asteroids The Ld type is a grouping proposed in the SMASS classification for asteroids with an L-like flat spectrum longwards of 0.75 μm, but even redder in visible wavelengths, like the D-type. An example may be 728 Leonisis, although it has also been classified as an A-type. References See also * Asteroid spectral types An asteroid spectral type is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-type Asteroids (Tholen)
S-type asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are of this type, making it the second most common after the carbonaceous C-type. Characteristics S-type asteroids, with an astronomical albedo of typically 0.20, are moderately bright and consist mainly of iron- and magnesium- silicates. They are dominant in the inner part of the asteroid belt within 2.2 AU, common in the central belt within about 3 AU, but become rare farther out. The largest are 3 Juno (about 240–250 km across) and 15 Eunomia (230 km), with other large S-types being 29 Amphitrite, 532 Herculina and 7 Iris. These largest S-types are visible in 10x50 binoculars at most oppositions; the brightest, 7 Iris, can occasionally become brighter than +7.0, which is a higher magnitude than any asteroid except the unusually reflective 4 Vesta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as molar percentages of forsterite (Fo) and fayalite (Fa) (''e.g.'', Fo70Fa30). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photometry (astronomy)
Photometry, from Greek '' photo-'' ("light") and '' -metry'' ("measure"), is a technique used in astronomy that is concerned with measuring the flux or intensity of light radiated by astronomical objects. This light is measured through a telescope using a photometer, often made using electronic devices such as a CCD photometer or a photoelectric photometer that converts light into an electric current by the photoelectric effect. When calibrated against standard stars (or other light sources) of known intensity and colour, photometers can measure the brightness or apparent magnitude of celestial objects. The methods used to perform photometry depend on the wavelength region under study. At its most basic, photometry is conducted by gathering light and passing it through specialized photometric optical bandpass filters, and then capturing and recording the light energy with a photosensitive instrument. Standard sets of passbands (called a photometric system) are defined to allow a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Curve
In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequency interval or band. Light curves can be periodic, as in the case of eclipsing binaries, Cepheid variables, other periodic variables, and transiting extrasolar planets, or aperiodic, like the light curve of a nova, a cataclysmic variable star, a supernova or a microlensing event or binary as observed during occultation events. The study of the light curve, together with other observations, can yield considerable information about the physical process that produces it or constrain the physical theories about it. Variable stars Graphs of the apparent magnitude of a variable star over time are commonly used to visualise and analyse their behaviour. Although the categorisation of variable star types is increasingly done from their s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Isis
"The Isis" () is an alternative name for the River Thames, used from its source in the Cotswolds until it is joined by the Thame at Dorchester in Oxfordshire. It derives from the ancient name for the Thames, ''Tamesis'', which in the Middle Ages was believed to be a combination of "Thame" and "Isis". Notably, the Isis flows through the city of Oxford. Rowing The name "Isis" is especially used in the context of rowing at the University of Oxford. A number of rowing regattas are held on the Isis, including Eights Week, the most important Oxford University regatta, in the Trinity term (summer), Torpids in the Hilary term (early spring) and Christ Church Regatta for novices in the Michaelmas term (autumn). Because the width of the river is restricted at Oxford, rowing eights normally have a staggered start near Donnington Bridge and must then aim to "bump" the eight in front (i.e. catch up and touch or overlap with it sufficiently). The leading eight aims to "row over" (i.e. fin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isis Pogson
Isis Pogson, (born Elizabeth Isis Pogson; 28 September 1852 – 14 May 1945), was a British astronomer and meteorologist, who was one of the first women to be elected as a fellow of the Royal Astronomical Society. Biography Early life Pogson was born in Oxford, England, the eldest daughter of Norman Pogson by his first marriage to Elizabeth Jane Ambrose (died 1869). She was probably named after the River Isis, the part of the River Thames that flows through Oxford. Assisting astronomer Norman Pogson was an assistant at Radcliffe Observatory and then at Hartwell Observatory. He discovered the asteroid 42 Isis on 23 May 1856, for which he was awarded the Lalande Prize. The asteroid was named by Professor Manuel John Johnson, director of the Radcliffe Observatory, presumably in honour of Pogson's daughter Isis; it could also have been a reference to the River Isis. When her father became director of the Madras Observatory in Madras, India, in October 1860, he travelled to his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egyptian Goddess
Ancient Egyptian deities are the gods and goddesses worshipped in ancient Egypt. The beliefs and rituals surrounding these gods formed the core of ancient Egyptian religion, which emerged sometime in prehistory. Deities represented natural forces and phenomena, and the Egyptians supported and appeased them through offerings and rituals so that these forces would continue to function according to ''maat'', or divine order. After the founding of the Egyptian state around 3100 BC, the authority to perform these tasks was controlled by the pharaoh, who claimed to be the gods' representative and managed the temples where the rituals were carried out. The gods' complex characteristics were expressed in myths and in intricate relationships between deities: family ties, loose groups and hierarchies, and combinations of separate gods into one. Deities' diverse appearances in art—as animals, humans, objects, and combinations of different forms—also alluded, through symbolism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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