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Ursa Major Moving Group
The Ursa Major Moving Group, also known as Collinder 285 and the Ursa Major association, is the closest Stellar kinematics#Moving groups, stellar moving group – a set of stars with common velocities in space and thought to have a common origin in space and time. In the case of the Ursa Major group, all the stars formed about 300 million years ago. Its core is located roughly 80 light years away and part of the Local Bubble. It is rich in bright stars including most of the stars of the Big Dipper. Discovery and constituents All stars in the Ursa Major Moving Group are moving in roughly the same direction at similar velocities, and also have similar chemical compositions and estimated ages. This evidence suggests to astronomers that the stars in the group share a common origin. Based on the numbers of its constituent stars, the Ursa Major Moving Group is believed to have once been an open cluster, having formed from a protostellar nebula approximately 500 million years ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PSM V04 D306 Ursa Major
PSM, an acronym, may refer to: Organizations * Pakistan School Muscat, a Pakistani co-educational institute in Oman * Palestine Solidarity Movement, a student organization in the United States * Panhellenic Socialist Movement, a centre-left party in Greece * Parti Socialiste Mauricien, a political party in Mauritius, founded by Harish Boodhoo * Parti Sosialis Malaysia, a socialist political party in Malaysia * Sepaktakraw Association of Malaysia (; PSM), a national governing body in Malaysia * Photographic Society of Madras, a not for profit organisation involved in promoting photography, in Chennai * PlayStation: The Official Magazine, a magazine originally known as PlayStation Magazine or PSM * Ponce School of Medicine, a post-graduate medical school located in Ponce, Puerto Rico * Power Systems Manufacturing, a subsidiary of Alstom, specializing in aftermarket gas turbine servicing for power generating industry. * ''Poznańska Spółdzielnia Mieszkaniowa'', a housing cooperativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Aurigae
Beta Aurigae is a binary star system in the northern constellation of Auriga (constellation), Auriga. Its identifier is a Bayer designation that is Romanization of Greek, Latinized from β Aurigae, and abbreviated Beta Aur or β Aur. This star has the official name Menkalinan, pronounced . The combined apparent visual magnitude of the system is 1.9, making it the second-brightest member of the constellation after Capella (star), Capella. Using the stellar parallax, parallax measurements made during the Hipparcos mission, the distance to this star system can be estimated as , give or take a half-light-year margin of error. It is drifting closer to the Sun with a radial velocity of −18 km/s. Along their respective orbits around the Milky Way, Beta Aurigae and the Sun are closing in on each other, so that in around one million years it will become the brightest star in the night sky. It is predicted to come as close as in 1.31 million years. Nomenclature ''β ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ursa Majoris Gaia DR3
Ursa is a Latin word meaning bear. Derivatives of this word are ursine or Ursini. Ursa or URSA may also refer to: General * Ursa (Finland), a Finnish astronomical association * ''Ursa'' (spider), a spider genus in the family Araneidae * Ursa Major, the Great Bear constellation * Ursa Minor, the Small Bear constellation * '' Ursa the Bear'', a former public sculpture in Bristol * HMS ''Ursa'', the name of two ships of the Royal Navy * Blackmagic URSA, a digital movie camera Places * Ursa, Illinois, a village in the United States * Ursa, a village in Gârcov Commune, Olt County, Romania * Ursa Motoșeni, the former name of Motoșeni Commune, Bacău County, Romania * Ursolovo - place in Radilovo - Bulgaria People * Urša, feminine given name Media * Ursa, a monster in the film ''After Earth'' * Ursa, a mother of Zuko and Azula in the franchise '' Avatar: The Last Airbender'' * Ursa, a girlfriend of Bear in the television series ''Bear in the Big Blue House'' * Ursa, a char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mizar And Alcor
Mizar and Alcor are two stars forming a naked eye double in the handle of the Big Dipper (or Plough) asterism in the constellation of Ursa Major. Their magnitudes are 2.2 and 3.9, and the pair can easily be seen without the aid of a telescope. Mizar and its fainter companion Alcor are actually a four-star binary system consisting of two pairs of double stars that are gravitationally bound to each other. The traditional name Mizar derives from the Arabic المئزر or miʼzar, meaning "apron; wrapper, covering, cover". Alcor was originally the Arabic سها or Suhā/Sohā, meaning either the "forgotten" or "neglected" one. The ancient Persians and the Bedouins used distinguishing Mizar and Alcor as a test of vision. Mizar, also designated Zeta Ursae Majoris (ζ Ursae Majoris, abbreviated Zeta UMa, ζ UMa), is itself a quadruple system and Alcor, also designated 80 Ursae Majoris (80 UMa), is a binary, the pair together forming a sextuple system. In fact, Mizar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main-sequence
In astronomy, the main sequence is a classification of stars which appear on plots of stellar color versus brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or dwarf stars, and positions of stars on and off the band are believed to indicate their physical properties, as well as their progress through several types of star life-cycles. These are the most numerous true stars in the universe and include the Sun. Color-magnitude plots are known as Hertzsprung–Russell diagrams after Ejnar Hertzsprung and Henry Norris Russell. After condensation and ignition of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass but also based on its chemical composition and age. The cores of main-sequence stars are in hydrostatic equilibrium, where outward thermal p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Classification
In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grating into a spectrum exhibiting the Continuum (spectrum), rainbow of colors interspersed with spectral lines. Each line indicates a particular chemical element or molecule, with the line strength indicating the abundance of that element. The strengths of the different spectral lines vary mainly due to the temperature of the photosphere, although in some cases there are true abundance differences. The ''spectral class'' of a star is a short code primarily summarizing the ionization state, giving an objective measure of the photosphere's temperature. Most stars are currently classified under the Morgan–Keenan (MK) system using the letters ''O'', ''B'', ''A'', ''F'', ''G'', ''K'', and ''M'', a sequence from the hottest (''O'' type) to the cool ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaia Mission
''Gaia'' was a space observatory of the European Space Agency (ESA) that was launched in 2013 and operated until March 2025. The spacecraft was designed for astrometry: measuring the positions, distances and motions of stars with unprecedented precision, and the positions of exoplanets by measuring attributes about the stars they orbit such as their apparent magnitude and color. , the mission data processing continues, aiming to construct the largest and most precise 3D space catalog ever made, totalling approximately 1 billion astronomical objects, mainly stars, but also planets, comets, asteroids and quasars, among others. To study the precise position and motion of its target objects, the spacecraft monitored each of them about 70 times over the five years of the nominal mission (2014–2019), and about as many during its extension. Due to its detectors not degrading as fast as initially expected, the mission was given an extension. As of March 2023, the spacecraft had en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Space Agency
The European Space Agency (ESA) is a 23-member International organization, international organization devoted to space exploration. With its headquarters in Paris and a staff of around 2,547 people globally as of 2023, ESA was founded in 1975 in the context of European integration. Its 2025 annual budget was €7.7 billion. The ESA Human and Robotic Exploration programme includes human spaceflight (mainly through participation in the International Space Station programme); as well as the launch and operation of missions to Mars and Moon. Further activities include science missions to Jupiter, Mercury, the Sun, Earth observation, Asteroid impact avoidance and Telecommunications missions, designing launch vehicles; and maintaining Europe's Spaceport, the Guiana Space Centre at Kourou (French Guiana). Further programmes include space safety, satellite navigation, applications and commercialisation. The main European launch vehicle Ariane 6 is operated through Arianespace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Parallax
Stellar parallax is the apparent shift of position (''parallax'') of any nearby star (or other object) against the background of distant stars. By extension, it is a method for determining the distance to the star through trigonometry, the stellar parallax method. Created by the different orbital positions of Earth, the extremely small observed shift is largest at time intervals of about six months, when Earth arrives at opposite sides of the Sun in its orbit, giving a baseline (the shortest side of the triangle made by a star to be observed and two positions of Earth) distance of about two astronomical units between observations. The parallax itself is considered to be half of this maximum, about equivalent to the observational shift that would occur due to the different positions of Earth and the Sun, a baseline of one astronomical unit (AU). Stellar parallax is so difficult to detect that its existence was the subject of much debate in astronomy for hundreds of years. Thomas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Magnitude
Apparent magnitude () is a measure of the Irradiance, brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction (astronomy), extinction of the object's light caused by interstellar dust along the sightline, line of sight to the observer. Unless stated otherwise, the word ''magnitude'' in astronomy usually refers to a celestial object's apparent magnitude. The magnitude scale likely dates to before the ancient Ancient Greek astronomy#Astronomy in the Greco-Roman and Late Antique eras, Roman astronomer Ptolemy, Claudius Ptolemy, whose Star catalogue, star catalog popularized the system by listing stars from First-magnitude star, 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined to closely match this historical system by Norman Robert Pogson, Norman Pogson in 1856. The scale is reverse logarithmic scale, logarithmic: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 of the Solar System. It is measured relative to the distant stars or a stable reference such as the International Celestial Reference Frame (ICRF). Patterns in proper motion reveal larger structures like stellar streams, the general rotation of the Milky Way disk, and the random motions of stars in the Galactic halo. The components for proper motion in the equatorial coordinate system (of a given epoch, often J2000.0) are given in the direction of right ascension (''μ''α) and of declination (''μ''δ). Their combined value is computed as the ''total proper motion'' (''μ''). It has dimensions of angle per time, typically arcseconds per year or milliarcseconds per year. Knowledge of the proper motion, distance, and radial velocity allows calculations of an object's motion from the Solar System's frame of reference an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
