PV Telescopii Variable

picture info	PV Telescopii Variable PV Telescopii variable is a type of variable star that is established in the ''General Catalogue of Variable Stars'' with the acronym PVTEL. This class of variables are defined as "helium supergiant Bp stars with weak hydrogen lines and enhanced lines of He and C". That is, the hydrogen spectral lines of these stars are weaker than normal for a star of stellar class B, while the lines of helium and carbon are stronger. They are a type of extreme helium star. The prototype for this category of variable is PV Telescopii, which undergoes small but complex luminosity variations and radial velocity fluctuations. The PV Tel stars are extremely hydrogen-deficient compared to other B-class stars and vary in luminosity on time scales ranging from a few hours to several years. As of 2008, there are twelve confirmed PV Tel variables in the ''General Catalogue of Variable Stars''. PV Telescopii variables are subdivided into three distinct types on the basis of spectral type In astronom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Eclipsing Binary A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in which case they are called ''visual binaries''. Many visual binaries have long orbital periods of several centuries or millennia and therefore have orbits which are uncertain or poorly known. They may also be detected by indirect techniques, such as spectroscopy (''spectroscopic binaries'') or astrometry (''astrometric binaries''). If a binary star happens to orbit in a plane along our line of sight, its components will eclipse and transit each other; these pairs are called ''eclipsing binaries'', or, together with other binaries that change brightness as they orbit, ''photometric binaries''. If components in binary star systems are close enough they can gravitationally distort their mutual outer stellar atmospheres. In some cases, these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	BD -9 4395 BD, Bd or bd may refer to: In arts and entertainment * B. D. (Doonesbury), a major character in the ''Doonesbury'' comic strip * ''Bande dessinée'' (or "bédé"), a French term for comics * Bass drum, in sheet music notation * Brahe Djäknar, a Finnish choir * Broder Daniel, a Swedish indie pop band * ''Ben Drowned'', a web serial and web series, focused on the character of the same name * ВD, shorthand name for the Russian gaming magazine, ''Velikij Drakon'', where the "В" character is actually the Russian letter "ve". * Bette Davis's production company In business Business / Technology * B&D Australia, manufacturing company * Big data, a marketing term for technology of large data sets * Broker-dealer * Business day, a day of the week on which business is conducted * Business development, techniques aimed at attracting customers and penetrating markets * Business directory, a website or printed listing of information which lists all businesses within some category Busin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	CPD -58 2721 CPD may refer to: Science and technology * CPD (gene), a human gene encoding the protein Carboxypeptidase D * Chronic pulmonary disease, a pathological condition * Cephalopelvic disproportion, when the capacity of the pelvis is inadequate to allow the fetus to negotiate the birth canal * Cyclobutane pyrimidine dimer, a common UV product * Cyclopentadiene, an organic compound * Canonical polyadic decomposition, in mathematics * Copy/Paste Detector, software to find duplicate computer code * Chemical compound, a substance formed by chemical union * Cyproterone acetate, a progestin and antiandrogen * Conditional probability distribution, a kind of distribution in statistics Organizations * Centre for Policy Development, an Australian think tank * Centre for Policy Dialogue, Bangladesh * Centres of Plant Diversity, a classification initiative * Commission on Presidential Debates, a US nonprofit * Committee on the Present Danger, an American foreign policy interest group Police * Cambr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	V1920 Cygni V19 may refer to: * * LFG Stralsund V 19 Putbus, a German floatplane * V-19 Torrent starfighter, a fictional vehicle in the ''Star Wars'' franchise * Vivo V19, a smartphone * V19, a family history of other conditions, in the ICD-9 V codes (E000) External cause status * External cause status Civilian activity done for income or pay Military activity Volunteer activity Other external cause status ** Unspecified external cause status (E001–E030) Activity * Activ ... {{Letter-NumberCombDisambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	NO Serpentis No (and variant writings) may refer to one of these articles: English language * ''Yes'' and ''no'' (responses) * A determiner in noun phrases Alphanumeric symbols * No (kana), a letter/syllable in Japanese script * No symbol, displayed 🚫 * Numero sign, a typographic symbol for the word 'number', also represented as "No." or similar variants Geography * Norway (ISO 3166-1 country code NO) Norwegian language (ISO 639-1 code "no"), a North Germanic language that is also the official language of Norway .no, the internet ccTLD for Norway * Lake No, in South Sudan * No, Denmark, village in Denmark * Nō, Niigata, a former town in Japan * No Creek (other) * Acronym for the U.S. city of New Orleans, Louisiana or its professional sports teams New Orleans Saints of the National Football League New Orleans Pelicans of the National Basketball Association Arts and entertainment Film and television * ''Dr. No'' (film), a 1962 ''James Bond'' film Julius No ... [...More Info...] [...Related Items...] OR:** [Wikipedia] [Google] [Baidu]
	HD 124448 HD 124448, also called Popper's Star and V821 Centauri, is an extreme helium star in the Centaurus constellation. Discovered by astronomer Daniel Popper, this star has a spectral classification In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the ... of B2-B3 and a radius of . References Centaurus B-type stars PV Telescopii variables 124448 Centauri, V821 069619 {{supergiant-star-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	CD -35 11760 The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then released in October 1982 in Japan and branded as '' Digital Audio Compact Disc''. The format was later adapted (as CD-ROM) for general-purpose data storage. Several other formats were further derived, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video CD (VCD), Super Video CD (SVCD), Photo CD, Picture CD, Compact Disc-Interactive (CD-i) and Enhanced Music CD. Standard CDs have a diameter of and are designed to hold up to 74 minutes of uncompressed stereo digital audio or about 650 MiB of data. Capacity is routinely extended to 80 minutes and 700 MiB by arranging data more closely on the same sized disc. The Mini CD has various diameters ranging from ; they are sometimes used for CD singles, storing up to 24 minu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	BD +1 4381 BD, Bd or bd may refer to: In arts and entertainment * B. D. (Doonesbury), a major character in the ''Doonesbury'' comic strip * ''Bande dessinée'' (or "bédé"), a French term for comics * Bass drum, in sheet music notation * Brahe Djäknar, a Finnish choir * Broder Daniel, a Swedish indie pop band * ''Ben Drowned'', a web serial and web series, focused on the character of the same name * ВD, shorthand name for the Russian gaming magazine, ''Velikij Drakon'', where the "В" character is actually the Russian letter "ve". * Bette Davis's production company In business Business / Technology * B&D Australia, manufacturing company * Big data, a marketing term for technology of large data sets * Broker-dealer * Business day, a day of the week on which business is conducted * Business development, techniques aimed at attracting customers and penetrating markets * Business directory, a website or printed listing of information which lists all businesses within some category Busin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	KS Persei KS Persei is a binary system in the equatorial constellation of Perseus. It is sometimes known as Bidelman's Star, named after William P. Bidelman. The star is invisible to the naked eye with a mean apparent visual magnitude of 7.70. As of 2018, the structure and evolutionary history of this system remain uncertain, although some form of mass transfer is likely to have occurred to explain the observed properties. The peculiar nature of the spectra for this star was noted in the '' Henry Draper Catalogue'' and was the subject of a study by W. P. Bidelman published in 1950. He found extremely weak lines of hydrogen, similar to those for Upsilon Sagittarii but at a lower temperature. The data strongly suggested the star has an abnormally low abundance of hydrogen in the stellar atmosphere. Bidelman noted that the radial velocity of the star is variable, demonstrating that it has an unseen companion. Preliminary orbital elements for this single-lined spectroscopic binary were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]