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Phosphorus Mononitride
Phosphorus mononitride is an inorganic compound with the chemical formula . Containing only phosphorus and nitrogen, this material is classified as a binary nitride. From the Lewis structure perspective, it can be represented with a P-N triple bond with a lone pair on each atom. It is isoelectronic with , CO, , CS, , and SiO. The compound is highly unstable in standard conditions, tending to rapidly self polymerize. It can be isolated within argon and krypton matrices at . Due to its instability, documentation of reactions with other molecules is limited. Most of its reactivity has thus far been probed and studied at transition metal centers. Phosphorus mononitride was the first identified phosphorus compound in the interstellar medium and is even thought to be an important molecule in the atmospheres of Jupiter and Saturn. Discovery and interstellar occurrence The existence of free, gas-phase phosphorus mononitride was confirmed spectroscopically in 1934 by Nobel laure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Phosphorus Monoxide
Phosphorus monoxide is an unstable radical inorganic compound with molecular formula P O. Phosphorus monoxide is notable as one of the few molecular compounds containing phosphorus that has been detected outside of Earth. Other phosphorus containing molecules found in space include PN, PC, PC2, HCP and PH3. It was detected in the circumstellar shell of VY Canis Majoris and in the star forming region catalogued as AFGL 5142. The compound has been found to have been initially produced in star-forming regions, and speculated to be carried by interstellar comets throughout outer space, including to the early Earth. Phosphorus monoxide plays a role in the phosphorescence of phosphorus. Discovery In 1894 W. N. Hartley was the first to report an observation of ultraviolet emission from a phosphorus compound, that was later expanded on by Geuter. The source of the spectral lines and bands were known to be related to phosphorus, but the exact nature was unknown. In 1927 H. J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sculptor Galaxy
The Sculptor Galaxy (also known as the Silver Coin Galaxy, Silver Dollar Galaxy, NGC 253, or Caldwell 65) is an intermediate spiral galaxy in the constellation Sculptor. The Sculptor Galaxy is a starburst galaxy, which means that it is currently undergoing a period of intense star formation. Observation Observational history The galaxy was discovered by Caroline Herschel in 1783 during one of her systematic comet searches. About half a century later, John Herschel observed it using his 18-inch metallic mirror reflector at the Cape of Good Hope. He wrote: "very bright and large (24′ in length); a superb object.... Its light is somewhat streaky, but I see no stars in it except 4 large and one very small one, and these seem not to belong to it, there being many near..." In 1961, Allan Sandage wrote in the ''Hubble Atlas of Galaxies'' that the Sculptor Galaxy is "the prototype example of a special subgroup of Sc systems....photographic images of galaxies of the group are domin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Interstellar Cloud
An interstellar cloud is an accumulation of gas, plasma, and cosmic dust in galaxies. Put differently, an interstellar cloud is a denser-than-average region of the interstellar medium, the matter and radiation that exists in the space between the star systems in a galaxy. Depending on the density, size, and temperature of a given cloud, its hydrogen can be neutral, making an H I region; ionized, or plasma making it an H II region; or molecular, which are referred to simply as molecular clouds, or sometime dense clouds. Neutral and ionized clouds are sometimes also called ''diffuse clouds''. An interstellar cloud is formed by the gas and dust particles from a red giant in its later life. Chemical compositions The chemical composition of interstellar clouds is determined by studying electromagnetic radiation that they emanate, and we receive – from radio waves through visible light, to gamma rays on the electromagnetic spectrum – that we receive from them. Large radio tele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
67P/Churyumov–Gerasimenko
67P/Churyumov–Gerasimenko (abbreviated as 67P or 67P/C–G) is a Jupiter-family comet. It is originally from the Kuiper belt and has an orbital period of 6.45 years as of 2012, a rotation period of approximately 12.4 hours, and a maximum velocity of . Churyumov–Gerasimenko is approximately at its longest and widest dimensions. It was first observed on photographic plates in 1969 by Soviet astronomers Klim Churyumov, Klim Ivanovych Churyumov and Svetlana Gerasimenko, Svetlana Ivanovna Gerasimenko, after whom it is Naming of comets, named. It most recently came to Perihelion and aphelion, perihelion (closest approach to the Sun) on 2 November 2021, and will next come to perihelion on 9 April 2028. Churyumov–Gerasimenko was the destination of the European Space Agency's Rosetta (spacecraft), ''Rosetta'' mission, launched on 2 March 2004. ''Rosetta'' space rendezvous, rendezvoused with Churyumov–Gerasimenko on 6 August 2014 and entered orbit on 10 September 2014. ''Rosetta' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Rosetta (spacecraft)
''Rosetta'' was a space probe built by the European Space Agency that launched on 2 March 2004. Along with ''Philae'', its lander module, ''Rosetta'' performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft performed flybys of Earth, Mars, and the asteroids 21 Lutetia and 2867 Šteins. It was launched as the third cornerstone mission of the ESA's Horizon 2000 programme, after ''SOHO' Cluster'' and '' XMM-Newton''. On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvers to eventually orbit the comet at distances of . On 12 November, its lander module ''Philae'' performed the first successful landing on a comet, though its battery power ran out two days later. Communications with ''Philae'' were briefly restored in June and July 2015, but due to diminishing solar power, ''Rosetta'' communications module with the lander was turned off on 27 July 2016. On 30 September 2016, the ''Rosett ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Atacama Large Millimeter Array
The Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of 66 radio telescopes in the Atacama Desert of northern Chile, which observe electromagnetic radiation at millimeter and submillimeter wavelengths. The array has been constructed on the elevation Chajnantor plateau – near the Llano de Chajnantor Observatory and the Atacama Pathfinder Experiment. This location was chosen for its high elevation and low humidity, factors which are crucial to reduce noise and decrease signal attenuation due to Earth's atmosphere. ALMA provides insight on star birth during the early Stelliferous era and detailed imaging of local star and planet formation. ALMA is an international partnership amongst Europe, the United States, Canada, Japan, South Korea, Taiwan, and Chile. Costing about US$1.4 billion, it is the most expensive ground-based telescope in operation. ALMA began scientific observations in the second half of 2011 and the first images were rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
NML Cygni
NML Cygni or V1489 Cygni (abbreviated to NML Cyg or V1489 Cyg) is a M-type star, red hypergiant or red supergiant (RSG) in the constellation Cygnus (constellation), Cygnus. It is possibly one of the List of largest stars, largest known stars currently known, and is also possibly list of most luminous stars, one of the most luminous and List of most massive stars, massive cool hypergiants, as well as one of the most luminous stars in the Milky Way. The distance of NML Cygni from Earth is estimated to be around 1.6 Parsec#Parsecs and kiloparsecs, kpc, about . It is a part of the Cygnus OB2 association, one of the closest massive associations to the Sun, spanning nearly 2° on the sky or ~ in radius at the distance of . Based on the estimated distance and a measurement of its angular diameter of , NML Cygni's physical radius is estimated to be . If placed at the center of the Solar System, its surface would potentially extend past the orbit of Jupiter. Observational history ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
R Cassiopeiae
R Cassiopeiae is a variable star in the northern constellation of Cassiopeia. It is located approximately 570 light years distant from the Sun, but is drifting closer with a radial velocity of −23 km/s. This is a pulsating Mira-type variable star with a brightness that varies from magnitude +4.4 down to +13.5 over a period of 433.6 days. At its maximum brightness, R Cassiopeiae is visible to the naked eye as a faint, red-hued star. Norman Robert Pogson discovered the star, in 1853. This aging red giant star has a stellar classification that varies from M6e to M10e, where the 'e' suffix indicates emission features in the spectrum. Currently on the asymptotic giant branch, it has 59% of the mass of the Sun with an oxygen rich chemical abundance. Having exhausted the supply of hydrogen at its core, the star has expanded to 263 times the Sun's radius. On average, the star is radiating 3,837 times the luminosity of the Sun from its swollen photosphere with an eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
TX Camelopardalis
TX Camelopardalis (abbreviated TX Cam) is a Mira-type variable star in the constellation Camelopardalis. It is a classical long period variable star with pulsational period of 558.7 days. Water maser A maser is a device that produces coherent electromagnetic waves ( microwaves), through amplification by stimulated emission. The term is an acronym for microwave amplification by stimulated emission of radiation. Nikolay Basov, Alexander Pr ...s have been observed around the star. References Camelopardalis Mira variables Camelopardalis, TX M-type giants {{var-star-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
VY Canis Majoris
VY Canis Majoris (abbreviated to VY CMa) is an extreme oxygen-rich red hypergiant or red supergiant (O-rich RHG or RSG) and pulsating variable star from the Solar System in the slightly southern constellation of Canis Major. It is one of the largest known stars, one of the most luminous and massive red supergiants, and one of the most luminous stars in the Milky Way. No evidence has been found that it is part of a multiple-star system. Its great infrared (IR) excess makes it one of the brightest objects in the local part of the galaxy ( Orion Arm) at wavelengths of 5 to 20 microns (μm) and indicates a dust shell or heated disk. It is about times the mass of the Sun (). It is surrounded by a complex asymmetric circumstellar envelope (CSE) caused by its mass loss. It produces strong molecular maser emission and was one of the first radio masers discovered. VY CMa is embedded in the large molecular cloud Sh2-310, a large, quite local star-forming H II region— ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Methylidynephosphane
Methylidynephosphane (phosphaethyne) is a chemical compound with the chemical formula . It was the first phosphaalkyne compound discovered, containing the unusual C≡P carbon-phosphorus triple bond. Although isolated samples of methylidynephosphane are impractical, other derivatives have been well studied such as ''tert''-butylphosphaacetylene. The conjugate base of methylidynephosphane is cyaphide. Description Methylidynephosphane is the phosphorus analogue of hydrogen cyanide, with the nitrile nitrogen replaced by phosphorus. Methylidynephosphane can be synthesized via the reaction of phosphine with carbon, but it is extremely reactive and polymerises readily at temperatures above −120 °C. However, several types of derivatives, with bulky groups, such as ''tert''-butyl or trimethylsilyl, substituted for the hydrogen atom, are much more stable, and are useful reagents for the synthesis of various organophosphorus compounds. The (cyaphate) and (thiocyaphate) anions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
