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Musca
is a small constellation in the deep southern sky. It was one of 12 constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman, and it first appeared on a celestial globe in diameter published in 1597 (or 1598) in Amsterdam by Plancius and Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in Johann Bayer's '' Uranometria'' of 1603. It was also known as for 200 years. Musca remains below the horizon for most Northern Hemisphere observers. Many of the constellation's brighter stars are members of the Scorpius–Centaurus association, a loose group of hot blue-white stars that appears to share a common origin and motion across the Milky Way. These include Alpha, Beta, Gamma, Zeta2 and (probably) Eta Muscae, as well as HD 100546, a blue-white Herbig Ae/Be star that is surrounded by a complex debris disk containing a large planet or brown dwarf and possible protoplanet. Two further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Muscae
Beta Muscae, Latinized from β Muscae, is a binary star in the southern circumpolar constellation of Musca. With a combined apparent visual magnitude of 3.07, it is the second brightest star (or star system) in the constellation. Judging by the parallax results, it is located at a distance of roughly from the Earth. This is a binary star system with a period of about 194 years at an orbital eccentricity of 0.6. As of 2007, the two stars had an angular separation of 1.206 arcseconds at a position angle of 35°. The components are main sequence stars of similar size and appearance. The primary component, β Muscae A, has an apparent magnitude of 3.51, a stellar classification of B2 V, and about 7.35 times the Sun's mass. The secondary component, β Muscae B, has an apparent magnitude of 4.01, a stellar classification of B3 V, and is about 6.40 times the mass of the Sun. This is a confirmed member of the Scorpius–Centaurus association, which is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Muscae
Alpha Muscae, Latinized from α Muscae, is a star in the southern circumpolar constellation of Musca. With an apparent visual magnitude of +2.7, it is the brightest star in the constellation. The distance to this star has been determined using parallax measurements, giving an estimate of about from Earth. With a stellar classification of B2 IV-V, this star appears to be in the process of evolving away from the main sequence of stars like the Sun and turning a subgiant star, as the supply of hydrogen at its core becomes exhausted. It is larger than the Sun, with nearly nine times the mass and 5.2 times the radius. This star is radiating around 4,300 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of 20,400 K, giving it the blue-white hue of a B-type star. Alpha Muscae appears to be a Beta Cephei variable star. Telting and colleagues report it as a Beta Cephei with a high degree of confidence as they found regular puls ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta2 Muscae
Zeta2 Muscae, Latinized from ζ2 Muscae, is a star in the southern constellation of Musca. Its apparent magnitude is 5.16. This is a white main sequence star of spectral type A5V around 330 light-years distant from Earth. Like several other stars in the constellation, it is a member of the Lower Centaurus–Crux subgroup of the Scorpius–Centaurus association The Scorpius–Centaurus association (sometimes called Sco–Cen or Sco OB2) is the nearest OB association to the Sun. This stellar association is composed of three subgroups (Upper Scorpius, Upper Centaurus–Lupus, and Lower Centaurus–Crux) ..., a group of predominantly hot blue-white stars that share a common origin and proper motion across the galaxy. It is part of a triple star system with faint companions at 0.5 and 32.4 arc seconds distance. The former is an infrared source, the latter has a visual magnitude of 10.7. References Lower Centaurus Crux Musca Muscae, Zeta2 4703 060320 107566 BD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Muscae
γ Muscae, Latinised as Gamma Muscae, is a blue-white hued star in the southern circumpolar constellation of Musca, the Fly. It can be seen with the naked eye, having an apparent visual magnitude of 3.87. Based upon an annual parallax shift of 10.04 mas as seen from Earth, it is located about 325 light years from the Sun. This is a B-type main-sequence star with a stellar classification of B5 V. It is a variable star that ranges between magnitudes 3.84 and 3.86 over a period of 2.7 days, and is classed as a slowly pulsating B star. It is around five times as massive as the Sun. The star is spinning rapidly with a projected rotational velocity of 205 km/s. This is giving it an oblate shape with an equatorial bulge that is 7% larger than the polar radius. Gamma Muscae is a proper motion Proper motion is the astrometric measure of changes in the apparent places of stars or other celestial objects as they move relative to the center of mass o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Muscae
Eta Muscae is a multiple star system in the southern constellation of Musca. It is visible to the naked eye as a faint, blue-white hued point of light with an apparent visual magnitude of 4.79. The system is located around 406 light years away from the Sun. It is a member of the Lower Centaurs Crux subgroup of the Sco OB2 stellar association of co-moving stars. The two main components of this system form a double-lined spectroscopic binary with a period of 2.4 days in a circular orbit. They are a detached eclipsing binary with a spectral type of B8V and a brightness that dips by 0.05 magnitude once per orbit. This pair consists of two components of similar mass and type. Further away from the primary system are stars of magnitude 7.3 and 10, designated Eta Muscae B and C. It is unclear if these stars are gravitationally–bound to the main pair. Evidence for an additional component has been found with a 30-year cycle in the orbital behavior of the main pair. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LP 145-141
Gliese 440, also known as LP 145-141 or LAWD 37, is a white dwarf located from the Solar System in the constellation Musca, the nearest star in this constellation. It is the fourth closest white dwarf, after Sirius B, Procyon B, and van Maanen's star. Despite its closeness, Gliese 440 is intrinsically faint with just 0.05% the luminosity of the Sun, and can not be viewed to the naked eye with an apparent magnitude of +11.5. History of observations Gliese 440 is known at least from 1917, when its proper motion was published by R. T. A. Innes and H. E. Wood in Volume 37 of ''Circular of the Union Observatory''. The corresponding designation is UO 37. (Note: this designation is not unique for this star, that is all other stars, listed in the table in the Volume 37 of this Circular, also could be called by this name). Space motion Gliese 440 may be a member of the Wolf 219 moving group, which has seven possible members. These stars share a similar motion through space, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 100546
HD 100546, also known as KR Muscae, is a pre-main sequence star of spectral type B8 to A0 located from Earth in the southern constellation of Musca. The star is surrounded by a circumstellar disk from a distance of 0.2 to 4 AU, and again from 13 AU out to a few hundred AU, with evidence for a protoplanet forming at a distance of around 47 AU. Estimated to be less than 10 million years old, it belongs to Herbig Ae/Be stars, and also the nearest example to the Solar System. Planetary system The HD 100546 system as a whole has evidence for three protoplanets, thus it is considered an important evolutionary precursor to intermediate-mass stars with multiple super-jovian planets at moderate/wide separations like HR 8799. While other hypothetical planets have been claimed to exist around the star, none of the discoveries have been confirmed. Planet b In 2013, researchers reported that they had found what seems to be a planet in the process of being formed, emb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classical Cepheid Variable
Classical Cepheids are a type of Cepheid variable star. They are young, population I variable stars that exhibit regular radial pulsations with periods of a few days to a few weeks and visual amplitudes ranging from a few tenths of a magnitude up to about 2 magnitudes. Classical Cepheids are also known as Population I Cepheids, Type I Cepheids, and Delta Cepheid variables. There exists a well-defined relationship between a classical Cepheid variable's luminosity and pulsation period, securing Cepheids as viable standard candles for establishing the galactic and extragalactic distance scales. Hubble Space Telescope (HST) observations of classical Cepheid variables have enabled firmer constraints on Hubble's law, which describes the expansion rate of the observable Universe. Classical Cepheids have also been used to clarify many characteristics of our galaxy, such as the local spiral arm structure and the Sun's distance from the galactic plane. Around 3,600 classical Cepheids ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apus
Apus is a small constellation in the Southern Celestial Hemisphere, southern sky. It represents a bird-of-paradise, and its name means "without feet" in Greek language, Greek because the bird-of-paradise was once wrongly believed to lack feet. First depicted on a celestial globe by Petrus Plancius in 1598, it was charted on a star atlas by Johann Bayer in his 1603 ''Uranometria''. The French explorer and astronomer Nicolas Louis de Lacaille charted and gave the brighter stars their Bayer designations in 1756. The five brightest stars are all reddish in hue. Shading the others at apparent magnitude 3.8 is Alpha Apodis, an orange giant that has around 48 times the diameter and 928 times the luminosity of the Sun. Marginally fainter is Gamma Apodis, another aging giant star. Delta Apodis is a double star, the two components of which are 103 Minute and second of arc, arcseconds apart and visible with the naked eye. Two star systems have been found to have exoplanet, planets. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrus Plancius
Petrus Plancius (; born Pieter Platevoet ; 1552 – 15 May 1622) was a Dutch- Flemish astronomer, cartographer and clergyman. Born, in Dranouter, now in Heuvelland, West Flanders, he studied theology in Germany and England. At the age of 24 he became a minister in the Dutch Reformed Church. Plancius fled from Brussels to Amsterdam to avoid religious persecution by the Inquisition after the city fell into Spanish hands in 1585. In Amsterdam he became interested in navigation and cartography and, having access to nautical charts recently brought from Portugal, he was soon recognized as an expert on safe maritime routes to India and the nearby "spice islands". This enabled colonies and port trade in both, including what would become the Dutch East Indies, named after the Dutch East India Company set up in 1602. He saw strong potential in the little-mapped Arctic Sea and strongly believed in the idea of a Northeast Passage until the failure of Willem Barentsz's third vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Family
Constellation families are collections of constellations sharing some defining characteristic, such as proximity on the celestial sphere, common historical origin, or common mythological theme. In the Western tradition, most of the northern constellations stem from Ptolemy's list in the ''Almagest'' (which in turn has roots that go back to Mesopotamian astronomy), and most of the far southern constellations were introduced by sailors and astronomers who traveled to the south in the 16th to 18th centuries. Separate traditions arose in India and China. Menzel's families Donald H. Menzel, director of the Harvard Observatory, gathered several traditional groups in his popular account, ''A Field Guide to the Stars and Planets'' (1975), and adjusted and regularized them so that his handful of groups covered all 88 of the modern constellations. Of these families, one (Zodiac) straddles the ecliptic which divides the sky into north and south; one (Hercules) has nearly equal porti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellations were likely defined in prehistory. People used them to relate stories of their beliefs, experiences, creation myth, creation, and mythology. Different cultures and countries invented their own constellations, some of which lasted into the early 20th century before today's constellations were internationally recognized. The recognition of constellations has changed significantly over time. Many changed in size or shape. Some became popular, only to drop into obscurity. Some were limited to a single culture or nation. Naming constellations also helped astronomers and navigators identify stars more easily. Twelve (or thirteen) ancient constellations belong to the zodiac (straddling the ecliptic, which the Sun, Moon, and planets all traver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
