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List Of Stars In Mensa
This is the list of notable stars in the constellation Mensa (constellation), Mensa, sorted by decreasing brightness. See also *List of stars by constellation References * * * * * * * {{Stars of Mensa Mensa (constellation), *List Lists of stars by constellation, Mensa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make them appear as fixed points of light. The most prominent stars have been categorised into constellations and asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its total mass is the main factor determining its evolution and eventual fate. A star shines for most of its active life due t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Star
In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a binary system of stars in mutual orbit, gravitationally bound to each other) or is an ''optical double'', a chance line-of-sight alignment of two stars at different distances from the observer. Binary stars are important to stellar astronomers as knowledge of their motions allows direct calculation of stellar mass and other stellar parameters. The only (possible) case of "binary star" whose two components are separately visible to the naked eye is the case of Mizar and Alcor (though actually a multiple-star system), but it is not known for sure whether Mizar and Alcor are gravitationally bound. Since the beginning of the 1780s, both professional and amateur double star observers have telescopically measured the distances and angles betwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Mensae
Delta Mensae, Latinized from δ Mensae, is a binary star system in the southern constellation of Mensa. It is faintly visible to the naked eye, having an apparent visual magnitude of 5.69. Based upon an annual parallax shift of 7.70 mas as seen from the Earth, it is 420 light years from the Sun. The primary, designated component A, is a K-type giant star with a stellar classification of K2/3 III. With the supply of hydrogen at its core exhausted, it has cooled and expanded to 13 times the radius of the Sun. The star is radiating 112 times the Sun's luminosity from its photosphere at an effective temperature of 5,180 K. Its companion, component B, is an A-type star about 0.9 magnitudes fainter than the primary. References {{DEFAULTSORT:Delta Mensae K-type giants A-type stars Binary stars Mensa (constellation) Mensae, Delta Durchmusterung objects 028525 028525 1426 Year 1426 ( MCDXXVI) was a common year starting on Tuesday (link will dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi Mensae C
Pi Mensae (π Men), also known as HD 39091, is a yellow dwarf star in the constellation of Mensa. This star has a high proper motion. The apparent magnitude is 5.67, which can be visible to the naked eye in exceptionally dark, clear skies. It is nearly 60 light-years away. The star is slightly larger than the Sun in terms of mass, size, luminosity, temperature and metallicity, and is about 730 million years younger. It hosts three known planets. Planetary system On October 15, 2001, an extrasolar planet was found orbiting the star. Pi Mensae b is one of the most massive planets ever discovered, and has a very eccentric orbit that takes approximately to complete. Because of its eccentricity, and being a massive brown dwarf that passes through the habitable zone, it would have disrupted the orbits of any Earth-like planets, and possibly thrown them into the star, or out into the interstellar medium. Incorporating more accurate ''Hipparcos'' data yields a mass range f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi Mensae B
Pi Mensae b (π Men b, π Mensae b), also known as HD 39091 b, is an extrasolar planet approximately 59 light-years away in the constellation of Mensa. The planet was announced orbiting the yellow main-sequence star Pi Mensae in October 2001. Detection and discovery On October 15, 2001, a team of astronomers including Jones, Butler, Tinney, Marcy, Penny, McCarthy, Carter, and Pourbaix announced the discovery of one of the most massive extrasolar planets that have yet been observed. It was discovered by the Anglo-Australian Planet Search team, using a Doppler spectrometer mounted on the Anglo-Australian Telescope. Physical characteristics Pi Mensae b has a very eccentric orbit and takes 5.72 years to revolve around the star. The semi-major axis of the planet's orbit around the star is 3.31 AU. This planet passes through the star's habitable zone at periastron (1.19 AU) while at apastron, it passes to around Jupiter-Sun distance (5.44 AU). The gravitational influence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extrasolar Planet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, multiple planets have been observed around a star. About 1 in 5 Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 statistic, Earth-sized means 1–2 Earth radii. planet in the habitable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi Mensae
Pi Mensae (π Men), also known as HD 39091, is a yellow dwarf star in the constellation of Mensa. This star has a high proper motion. The apparent magnitude is 5.67, which can be visible to the naked eye in exceptionally dark, clear skies. It is nearly 60 light-years away. The star is slightly larger than the Sun in terms of mass, size, luminosity, temperature and metallicity, and is about 730 million years younger. It hosts three known planets. Planetary system On October 15, 2001, an extrasolar planet was found orbiting the star. Pi Mensae b is one of the most massive planets ever discovered, and has a very eccentric orbit that takes approximately to complete. Because of its eccentricity, and being a massive brown dwarf that passes through the habitable zone, it would have disrupted the orbits of any Earth-like planets, and possibly thrown them into the star, or out into the interstellar medium. Incorporating more accurate ''Hipparcos'' data yields a mass range f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Mensae
Zeta Mensae, Latinized from ζ Mensae, is a solitary, white-hued star in the southern constellation of Mensa. It is faintly visible to the naked eye, having an apparent visual magnitude of +5.64. Based upon an annual parallax shift of as seen from GAIA, it is located around 394 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.088 due to interstellar dust. Eggen (1995) listed it as a proper motion candidate for membership in the IC 2391 supercluster. The stellar classification of A5 III suggests this is an A-type giant star. It is spinning rapidly, showing a projected rotational velocity of 200 km/s, giving the star an oblate shape with an equatorial bulge that is an estimated 26% larger than the polar radius. The star is radiating about 69 times the Sun's luminosity from its photosphere at an effective temperature of around 7,555 K. It displays a faint infrared excess at a wavelengt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Mensae
Epsilon Mensae, Latinized to ε Mensae, is a single star in the southern circumpolar constellation Mensa. It has an apparent magnitude of 5.52, making it faintly visible to the naked eye under ideal conditions. The object has a heliocentric radial velocity of , meaning it is receding from the Solar System, and is estimated to be 454 light years away. Epsilon Mensae has a stellar classification of K2/3 III — intermediate between a K2 and K3 giant star. It has 115% the mass of the Sun and an enlarged radius of . It shines at 170 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it an orange glow. Epsilon Mensae has a metallicity 49% that of the Sun and is believed to be a member of the young disk population. It spins leisurely with a projected rotational velocity Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu Mensae
μ Mensae, Latinized as Mu Mensae, is a solitary, blue-white-hued star in the southern constellation of Mensa. With an apparent visual magnitude of 5.54, it is just bright enough to be faintly visible to the naked eye. Based upon an annual parallax shift of 6.8405 mas as seen from GAIA, this star is located roughly 477 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.09 due to interstellar dust. The stellar classification of suggests that it is a B-type star with a spectrum that shows mixed traits of a giant and a bright giant star. It may be chemically peculiar with an overabundance of silicon in its outer atmosphere. The estimated radius of the star is 3.3 times that of the Sun. It is radiating 216 times the Sun's luminosity from its photosphere at an effective temperature of 12,550 K. References {{DEFAULTSORT:Mu Mensae B-type giants B-type bright giants Ap stars Mensa (constellation) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Star
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either: * Intrinsic variables, whose luminosity actually changes; for example, because the star periodically swells and shrinks. * Extrinsic variables, whose apparent changes in brightness are due to changes in the amount of their light that can reach Earth; for example, because the star has an orbiting companion that sometimes eclipses it. Many, possibly most, stars have at least some variation in luminosity: the energy output of the Sun, for example, varies by about 0.1% over an 11-year solar cycle. Discovery An ancient Egyptian calendar of lucky and unlucky days composed some 3,200 years ago may be the oldest preserved historical document of the discovery of a variable star, the eclipsing binary Algol. Of the modern astronomers, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Mensae
Eta Mensae, Latinized from η Mensae, is the Bayer designation for a solitary, orange-hued star in the southern constellation of Mensa. This object has an apparent visual magnitude of 5.47, which is sufficiently luminous to be faintly visible to the naked eye. Based upon an annual parallax shift of 4.88 mas as seen from Earth, this star is located roughly 670 light years from the Sun. This is an evolved K-type giant star with a stellar classification of K4 III. It is radiating 616 times the Sun's luminosity from its photosphere at an effective temperature of 4,055 K. The star displays an infrared excess that suggests the presence of circumstellar dust. Eta Mensae is a probable member of the stream of stars associated with the Hyades cluster. References {{DEFAULTSORT:Eta Mensae K-type giants Circumstellar disks Mensa (constellation) Mensae, Eta Durchmusterung objects 032440 1629 Events January–March * January 7– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
