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M94 Group
The M94 Group (Canes I Group or Canes Venatici I Group) is a loose, extended group of galaxies located about 13 million light-years away in the constellations Canes Venatici and Coma Berenices. The group is one of many groups that lies within the Virgo Supercluster (i.e. the Local Supercluster) and one of the closest groups to the Local Group. Although the galaxies in this cluster appear to be from a single large cloud-like structure, many of the galaxies within the group are only weakly gravitationally bound, and some have not yet formed stable orbits around the center of this group. Instead, most of the galaxies in this group appear to be moving with the expansion of the universe. Members The table below lists galaxies that have been consistently identified as group members in the Nearby Galaxies Catalog, the Lyons Groups of Galaxies (LGG) Catalog, and the three group lists created from the Nearby Optical Galaxy sample of Giuricin et al. Additionally, NGC 4105 and DDO 16 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a celestial body, as they are subject to perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodies) can be used to generate an ephemeris, a table of values giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press was the university press of the University of Cambridge. Granted a letters patent by King Henry VIII in 1534, it was the oldest university press in the world. Cambridge University Press merged with Cambridge Assessment to form Cambridge University Press and Assessment under Queen Elizabeth II's approval in August 2021. With a global sales presence, publishing hubs, and offices in more than 40 countries, it published over 50,000 titles by authors from over 100 countries. Its publications include more than 420 academic journals, monographs, reference works, school and university textbooks, and English language teaching and learning publications. It also published Bibles, runs a bookshop in Cambridge, sells through Amazon, and has a conference venues business in Cambridge at the Pitt Building and the Sir Geoffrey Cass Sports and Social Centre. It also served as the King's Printer. Cambridge University Press, as part of the University of Cambridge, was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4244
NGC 4244, also known as Caldwell 26, is an edge-on loose spiral galaxy in the constellation Canes Venatici, and is part of the M94 Group or Canes Venatici I Group, a galaxy group relatively close to the Local Group containing the Milky Way. In the sky, it is located near the yellow naked-eye star, Beta Canum Venaticorum, but also near the barred spiral galaxy NGC 4151 and irregular galaxy NGC 4214. With an apparent V-band magnitude of 10.18, NGC 4244 lies approximately 4.3 megaparsecs The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (AU), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, and ... (14 million light years) away. A nuclear star cluster and halo is located near the centre of this galaxy. See also * IC 5052 - a similar edge-on galaxy Notes References * * External links * * {{DEFAULTSORT:NGC 4244 Unbarred sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4214
NGC 4214 is a dwarf barred irregular galaxy located around 10 million light-years away in the constellation Canes Venatici. It was discovered on 28 April 1785 by German-British astronomer William Herschel. NGC 4214 is a member of the M94 Group. Characteristics NGC 4214 is both larger and brighter than the Small Magellanic Cloud as well as a starburst galaxy, with the largest star-forming regions (''NGC 4214-I'' and ''NGC 4214-II'') in the galaxy's center. Of the two, ''NGC 4214-I'' contains a super star cluster rich in Wolf–Rayet stars and ''NGC 4214-II'' is younger (age less than 3 million years), including a number of star clusters and stellar associations. NGC 4214 also has two older super star clusters, both with an age of 200 million years and respective masses of and solar masses. Two satellites are known to exist around the vicinity of NGC 4214. One is DDO 113, which has an absolute V-band magnitude of −12.2. It stopped star formation around 1 billion yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4190
NGC may refer to: Companies * NGC Corporation, the name of US electric company Dynegy, Inc. from 1995 to 1998 * National Gas Company of Trinidad and Tobago, a state-owned natural gas company in Trinidad and Tobago * National Grid plc, a former name of National Grid Electricity Transmission plc, the operator of the British electricity transmission system * Northrop Grumman Corporation, an aerospace and defense conglomerate formed from the merger of Northrop Corporation and Grumman Corporation in 1994 * Numismatic Guaranty Company, a coin certification company in the United States * National Garden Clubs, headquartered in St. Louis, Missouri * Network General Corporation, a defunct networking hardware company Other uses * National Gallery of Canada, an art gallery founded in 1880 in Ottawa, Canada * National Games of China, the national multi-sport event of China * National Geographic (American TV channel), a documentary and reality television channel established in the United Stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4144
NGC 4144 is a barred spiral galaxy located in the Ursa Major constellation. It was discovered by the German-born British astronomer William Herschel on April 10, 1788. The galaxy is also known by several other catalog names, including IRAS F12074+4644, 2MASX J12095860+4627258, UGC 7151, and PGC 38688. It has an apparent magnitude of 12.17 in the blue band. Description NGC 4144 is a barred spiral galaxy classified as Im/BCD C, meaning it displays features of both irregular and blue compact dwarf galaxies. The galaxy is situated approximately 40 million light-years away from Earth. It is part of the Ursa Major Group, which consists of several galaxies in close proximity to each other. NGC 4144 is particularly notable for its faint appearance and for being relatively difficult to observe without a telescope due to its low luminosity. Gallery NGC4144 - SDSS DR14.jpg, NGC 4144 by the Sloan Digital Sky Survey NGC 4144 GALEX WikiSky.jpg, NGC 4144 by GALEX NGC 4144 HST 9765 R814G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IC 4182
IC 4182 is a Magellanic spiral galaxy in the constellation Canes Venatici. The galaxy lies about 14 million light years away from Earth, which means, given its apparent dimensions, that IC 4182 is approximately 28,000 light years across. It was discovered by German astronomer Max Wolf on 21 March 1903. IC 4182 is seen nearly face-on. It has a low surface brightness disk with patch of star formation and no spiral pattern. The galaxy is close enough for its brightest stars to be resolvable through large telescopes, having a photometric blue filter apparent magnitude of 19.2, and a visual magnitude of around 20 for the brightest blue stars and around 21 for the brightest red stars. The density of ultraviolet sources decreases monotonically with radius. IC 4182 has been the home of one supernova, SN 1937C ( type Ia, mag. 8.4). Fritz Zwicky discovered the supernova, which was located 30 arcseconds north and 40 arcseconds east of the nucleus, on 24 August 1937. The supernova was a ... [...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] |
Second
The second (symbol: s) is a unit of time derived from the division of the day first into 24 hours, then to 60 minutes, and finally to 60 seconds each (24 × 60 × 60 = 86400). The current and formal definition in the International System of Units (SI) is more precise: The second ..is defined by taking the fixed numerical value of the caesium frequency, Δ''ν''Cs, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be when expressed in the unit Hz, which is equal to s−1. This current definition was adopted in 1967 when it became feasible to define the second based on fundamental properties of nature with caesium clocks. As the speed of Earth's rotation varies and is slowing ever so slightly, a leap second is added at irregular intervals to civil time to keep clocks in sync with Earth's rotation. The definition that is based on of a rotation of the earth is still used by the Universal Time 1 (UT1) system. Etymology "Minute" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilometer
The kilometre ( SI symbol: km; or ), spelt kilometer in American and Philippine English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is the preferred measurement unit to express distances between geographical places on land in most of the world; notable exceptions are the United States and the United Kingdom where the statute mile is used. Pronunciation There are two common pronunciations for the word. # # The first pronunciation follows a pattern in English whereby SI units are pronounced with the stress on the first syllable (as in kilogram, kilojoule and kilohertz) and the pronunciation of the actual base unit does not change irrespective of the prefix (as in centimetre, millimetre, nanometre and so on). It is generally preferred by the British Broadcasting Corporation (BBC), the Canadian Broadcasting Corporation (CBC), and the Australian Broadcasting Corporation (ABC). Man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and energy, is known as a #Blueshift, blueshift. The terms derive from the colours red and blue which form the extremes of the Visible spectrum, visible light spectrum. Three forms of redshift occur in astronomy and cosmology: Doppler effect, Doppler redshifts due to the relative motions of radiation sources, gravitational redshift as radiation escapes from gravitational potentials, and cosmological redshifts of all light sources proportional to their distances from Earth, a fact known as Hubble's law that implies the expansion of the universe, universe is expanding. All redshifts can be understood under the umbrella of Frame of reference, frame transformation laws. Gravitational waves, which also travel at Speed of light, the speed of light, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
