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NGC 1487
NGC 1487 is an irregular galaxy in the constellation Eridanus (constellation), Eridanus. It was discovered by James Dunlop on Oct 29, 1826. It is thought to be the remnant of two galaxies, which are the components NGC 1487E and NGC 1487W, that collided about 500 million years ago. See also * List of NGC objects (1001–2000) Gallery NGC 1487 GALEX WikiSky.jpg, NGC 1487 by GALEX References External links * Interacting galaxies Spiral galaxies Eridanus (constellation) NGC objects, 1487 Dorado Group Principal Galaxies Catalogue objects, 014117 {{Spiral-galaxy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New General Catalogue
The ''New General Catalogue of Nebulae and Clusters of Stars'' (abbreviated NGC) is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the ''Index Catalogues'' (abbreviated IC), describing a further 5,386 astronomical objects. Thousands of these objects are best known by their NGC or IC numbers, which remain in widespread use. The NGC expanded and consolidated the cataloguing work of William and Caroline Herschel, and John Herschel's ''General Catalogue of Nebulae and Clusters of Stars''. Objects south of the celestial equator are catalogued somewhat less thoroughly, but many were included based on observation by John Herschel or James Dunlop. The NGC contained multiple errors, but attempts to eliminate them were made by the ''Revised New General Catalogue'' (RNGC) by Jack W. Sulent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detaile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eridanus (constellation)
Eridanus () is a constellation in the southern celestial hemisphere. It is represented as a river. One of the 48 constellations listed by the 2nd century astronomer Ptolemy, it remains one of the 88 modern constellations. It is the sixth largest of the modern constellations, and the one that extends farthest in the sky from north to south. The same name was later taken as a Latin name for the real Po River and also for the name of a minor river in Athens. Features Stars At its southern end is the magnitude 0.5 star Achernar, designated Alpha Eridani. It is a blue-white hued main sequence star 144 light-years from Earth, whose traditional name means "the river's end". Achernar is a very peculiar star because it is one of the flattest stars known. Observations indicate that its radius is about 50% larger at the equator than at the poles. This distortion occurs because the star is spinning extremely rapidly. There are several other noteworthy stars in Eridanus, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, 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 Astronomical object, celestial body, as they are subject to Perturbation (astronomy), 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 Perihelion and aphelion, 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 bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metre Per Second
The metre per second is the unit of both speed (a scalar (physics), scalar quantity) and velocity (a Vector (mathematics and physics), vector quantity, which has direction and magnitude) in the International System of Units (SI), equal to the speed of a body covering a distance of one metre in a time of one second. The International System of Units, SI unit symbols are m/s, m·s−1, m s−1, or . Sometimes it is abbreviated as "mps". Conversions is equivalent to: : = 3.6 kilometres per hour, km/h (exactly) : ≈ 3.2808 feet per second (approximately) : ≈ 2.2369 miles per hour (approximately) : ≈ 1.9438 knot (unit), knots (approximately) 1 feet per second, foot per second = (exactly) 1 miles per hour, mile per hour = (exactly) 1 kilometres per hour, km/h = (exactly) Relation to other measures The benz, named in honour of Karl Benz, has been proposed as a name for one metre per second. Although it has seen some support as a practical unit, primarily from German ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphological Catalogue Of Galaxies
The Morphological Catalogue of Galaxies (MCG) or Morfologiceskij Katalog Galaktik, is a Russian catalogue of 30,642 galaxies compiled by Boris Vorontsov-Velyaminov and V. P. Arkhipova. It is based on scrutiny of prints of the Palomar Sky Survey plates, and putatively complete to a photographic magnitude of 15. Including galaxies to magnitude 16 would have resulted in an unmanageably large dataset. Publication The catalogue was published in five parts (chapters) between 1962 and 1974, the final chapter including a certain number of galaxies with a photographic magnitude above 15. HEASARC Gallery |
Lyon-Meudon Extragalactic Database
The Lyon-Meudon Extragalactic Database (LEDA) was a database of galaxies, created in 1983 at the Lyon Observatory. Each galaxy had a number assigned to it, which is now known as its PGC number. The Principal Galaxies Catalogue The Catalogue of Principal Galaxies (PGC) is an astronomical catalog published in 1989 that lists B1950 and J2000 equatorial coordinates and cross-identifications for 73,197 galaxies. It is based on the Lyon-Meudon Extragalactic Database (LEDA), ... (PGC), published in 1989, was based on the Lyon-Meudon Extragalactic Database and contained cross-identifications for it. LEDA was eventually merged with Hypercat to become HyperLEDA in 2000, itself also known as PGC2003. LEDA originally contained information on more than 60 parameters for about 100,000 galaxies, and now contains information on over 3 million celestial objects, of which about 1.5 million are galaxies. The database allows astronomers around the world access to its information. References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irregular Galaxy
An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure. Collectively they are thought to make up about a quarter of all galaxies. Some irregular galaxies were once spiral or elliptical galaxies but were deformed by an uneven external gravitational force. Irregular galaxies may contain abundant amounts of gas and dust. This is not necessarily true for dwarf irregulars. Irregular galaxies are commonly small, about one tenth the mass of the Milky Way galaxy. Due to their small sizes, they are prone to environmental effects like crashing with large galaxies and intergalactic clouds. Types There are three major types of irregular galaxies: * An Irr-I galaxy (Irr I) is an irregular galaxy that features some structure but not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Dunlop
James Dunlop FRSE (31 October 1793 – 22 September 1848) was a Scottish astronomer, noted for his work in Australia. He was employed by Sir Thomas Brisbane to work as astronomer's assistant at his private observatory, once located at Paramatta (now named Parramatta), New South Wales, about west of Sydney during the 1820s and 1830s. Dunlop was mostly a visual observer, doing stellar astrometry work for Brisbane, and after its completion, then independently discovered and catalogued many new telescopic southern double stars and deep-sky objects. He later became the Superintendent of Paramatta Observatory when it was finally sold to the New South Wales Government. Early life James Dunlop was born in Dalry, Ayrshire, Scotland, the son of John Dunlop, a weaver, and his wife Janet, ''née'' Boyle. Dunlop was educated at a primary school in Dalry and went to work at a thread factory in Beith when he was 14. He also attended a night-school in Beith kept by a man named Gardiner. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of NGC Objects (1001–2000)
This is a list of NGC objects 1001–2000 from the New General Catalogue (NGC). The astronomical catalogue is composed mainly of star clusters, nebulae, and galaxies. Other objects in the catalogue can be found in the other subpages of the list of NGC objects. The constellation information in these tables is taken from ''The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters by J. L. E. Dreyer'', which was accessed using the "VizieR Service". Galaxy morphological types and objects that are members of the Large Magellanic Cloud are identified using the ''NASA/IPAC Extragalactic Database''. The other data of these tables are from Wolfgang Steinicke's ''Revised New General Catalogue and Index Catalogue'' and/or the SIMBAD Astronomical Database unless otherwise stated. 1001–1100 1101–1200 1201–1300 1301–1400 1401–1500 1501–1600 1601–1700 1701–1800 1801–1900 1901–2000 See also * Lists of astronomical objects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GALEX
Galaxy Evolution Explorer (GALEX or Explorer 83 or SMEX-7) was a NASA orbiting space telescope designed to observe the universe in ultraviolet wavelengths to measure the history of star formation in the universe. In addition to paving the way for future ultraviolet missions, the space telescope allowed astronomers to uncover mysteries about the early universe and how it evolved, as well as better characterize phenomena like black holes and dark matter. The mission was extended three times over a period of 10 years before it was decommissioned in June 2013. GALEX was launched on 28 April 2003 and decommissioned in June 2013. Spacecraft The spacecraft was three-axis stabilized, with power coming from four fixed solar panels. The satellite bus is from Orbital Sciences Corporation based on OrbView 4. The telescope was a Modified Ritchey–Chrétien with a rotating grism. GALEX used the first ever UV light dichroic beam-splitter flown in space to direct photons to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interacting Galaxies
Interacting galaxies (''colliding galaxies'') are galaxies whose gravitational fields result in a disturbance of one another. An example of a minor interaction is a satellite galaxy disturbing the primary galaxy's spiral arms. An example of a major interaction is a galactic collision, which may lead to a galaxy merger. Satellite interaction A giant galaxy interacting with its satellites is common. A satellite's gravity could attract one of the primary's spiral arms. Alternatively, the secondary satellite can dive into the primary galaxy, as in the Sagittarius Dwarf Elliptical Galaxy diving into the Milky Way. That can possibly trigger a small amount of star formation. Such orphaned clusters of stars were sometimes referred to as "blue blobs" before they were recognized as stars. Galaxy collision Colliding galaxies are common during galaxy evolution. The extremely tenuous distribution of matter in galaxies means these are not collisions in the traditional sense of the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
