|
Ursa Major Cluster
The Ursa Major Cluster (Ursa Major I Cluster, UMa I ClG) is a spiral-rich galaxy cluster of the Virgo Supercluster. Some of its largest members are NGC 3631, NGC 3953, M109 on North (M109 Group) and NGC 3726, NGC 3938, NGC 4051 on South. The Ursa Major cluster is located at a distance of 18.6 megaparsecs (60 million light-years) and contains about 30% of the light emitted but only 5% of the mass of the nearby Virgo Cluster The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the Virgo constellation. Comprising approximately 1,300 (and possibly up to 2,000) member galaxies, the cluster forms the heart of the larger .... Reference External links Galaxy clusters Virgo Supercluster Ursa Major {{galaxy-cluster-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy Cluster
A galaxy cluster, or a cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by gravity, with typical masses ranging from 1014 to 1015 solar masses. Clusters consist of galaxies, heated gas, and dark matter. They are the second-largest known gravitationally bound structures in the universe after superclusters. They were believed to be the largest known structures in the universe until the 1980s, when superclusters were discovered. Small aggregates of galaxies are referred to as galaxy groups rather than clusters of galaxies. Together, galaxy groups and clusters form superclusters. Basic properties Galaxy clusters typically have the following properties: * They contain 100 to 1,000 galaxies, hot X-ray emitting gas and large amounts of dark matter. Details are described in the "Composition" section. * They have total masses of 1014 to 1015 solar masses. * They typically have diameters from 1 to 5 Mpc ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virgo Supercluster
The Local Supercluster (LSC or LS), or Virgo Supercluster is a formerly defined supercluster containing the Virgo Cluster and Local Group, which itself contains the Milky Way and Andromeda galaxies, as well as others. At least 100 galaxy groups and clusters are located within its diameter of 33 megaparsecs (110 million light-years). The Virgo Supercluster is one of about 10 million superclusters in the observable universe, with the main body of the supercluster, the Virgo Strand, connecting the Hydra-Centaurus and the Perseus–Pisces Superclusters. The Virgo Supercluster is part of the Pisces–Cetus Supercluster Complex, a galaxy filament. A 2014 study indicates that the Local Supercluster is only a part of an even greater supercluster, Laniakea, a larger group centered on the Great Attractor, thus subsuming the former Virgo Supercluster under Laniakea. Background Beginning with the first large sample of nebulae published by William and John Herschel in 1863, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 3631
NGC 3631 is a spiral galaxy located in the constellation Ursa Major. It is located at a distance of about 35 million light years from Earth, which, given its apparent dimensions, means that NGC 3631 is about 60,000 light years across. It was discovered by William Herschel on April 14, 1789. It is a grand design spiral galaxy seen face on. Characteristics NGC 3631 is a grand design spiral galaxy and features two principal spiral arms, which begin near the center. The two main arms branch into secondary arms with lower surface brightness. The galaxy shows moderate-to-high star formation rate and bright HII regions are present in all the arms. The star formation rate of the galaxy is 4.6 per year. Halton Arp observed "straight arms", and an "absorption tube crossing from inside to outside of southern arm" and added the galaxy to his Atlas of Peculiar Galaxies. At inclination of 17 degrees, the galaxy is seen nearly face on. The HI imaging shows the spiral arms distinguished well ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 3953
NGC 3953 is a barred spiral galaxy located in the constellation Ursa Major. It was discovered by Pierre Méchain on 12 March 1781. The galaxy is known to exhibit an inner ring structure that encircles the bar. NGC 3953 is a member of the M109 Group, a large group of galaxies located within the constellation Ursa Major that may contain over 50 galaxies. Two supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...e have been identified within NGC 3953: the type Ia supernova SN 2001dp and SN 2006bp. References External links Spiral Galaxy NGC 3953 – Supernova 2001 dp Barred spiral galaxies M109 Group Ursa Major 3953 06870 037306 17810312 {{Spiral-galaxy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 109
Messier 109 (also known as NGC 3992 or the Vacuum Cleaner Galaxy) is a barred spiral galaxy exhibiting a weak inner ring structure around the central bar approximately away in the northern constellation Ursa Major. M109 can be seen south-east of the star Phecda (γ UMa, Gamma Ursa Majoris). History Messier 109 was discovered by Pierre Méchain in 1781. Two years later Charles Messier catalogued the object, as an appended object to his publication. Between the 1920s through the 1950s, it was considered that Messier objects over 103 were not official, but later the additions, further referred target objects from Méchain, became more widely accepted. David H. Levy mentions the modern 110 object catalog while Sir Patrick Moore places the limit at 104 objects but has M105 to 109 listed as addenda. By the late 1970s all 110 objects are commonly used among astronomers and remain so. General information This galaxy is the most distant object in the Messier Catalog, followed by M9 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M109 Group M109.
The M109 Group (also known as the NGC 3992 Group or Ursa Major cloud) is a group of galaxies about 55 million light-years away in the constellation Ursa Major. The group is named after the brightest galaxy within the group, the spiral galaxy Spiral galaxies form a galaxy morphological classification, class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae'' 
Members The table below lists galaxies that have been consistently identified as group members in the Nearby Galaxies Catalog, the survey of Fouque et al.,[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 3726
NGC 3726 is a barred spiral galaxy located in the constellation Ursa Major. It is located at a distance of circa 45 million light years from Earth, which, given its apparent dimensions, means that NGC 3726 is about 85,000 light years across. It was discovered by William Herschel on February 5, 1788. Structure NGC 3726 is a spiral galaxy with a small bar, seen with medium inclination. The bar is 1.38 arcseconds across and it ends at an inner ring with 1.50 arcseconds diameter. The bluest regions of star formation are located at the ring. Three arms emanate from the ring. The southern is the brightest and the north is the best defined. The third arm emanates from the east side of the ring, moves towards NNW and then bends sharply to the southwest. The spiral arms are thick and well defined and can be traced for half a revolution. The arms then branch into fragments. The spiral pattern of the galaxy is a bit disturbed and asymmetrical. Numerous bright HII regions are present in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 3938
NGC 3938 is an unbarred spiral galaxy in the Ursa Major constellation. It was discovered by German-British astronomer William Herschel on 6 February 1788. It is one of the brightest spiral galaxies in the Ursa Major South galaxy group and is roughly 76,000 light years in diameter. It is approximately 41.4 million light years away from Earth. NGC 3938 is classified as type Sc under the Hubble sequence, a loosely wound spiral galaxy with a smaller and dimmer bulge. The spiral arms of the galaxy contain many areas of ionized atomic hydrogen gas, more so towards the center. NGC 3938 is a member of the NGC 4111 Group, which is part of the Ursa Major Cloud and is the second largest group in the cloud after the NGC 3992 Group. Supernovae and Luminous Red Nova Five supernovae have been identified within NGC 3938: * SN 1961U ( typeII, mag. 13.7) was discovered by Paul Wild on 28 December 1961. ote: some sources incorrectly list the discovery date as 2 January 1962.* SN 1964L ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4051
NGC 4051 is an intermediate spiral galaxy in the constellation of Ursa Major. It was discovered on 6 February 1788 by John Herschel. NGC 4051 contains a supermassive black hole with a mass of 1.73 million . This galaxy was studied by the Multicolor Active Galactic Nuclei Monitoring 2m telescope. The galaxy is a Seyfert galaxy that emits bright X-rays. However, in early 1998 the X-ray emission ceased as observed by the Beppo-SAX satellite. X-ray emission had risen back to normal by August 1998. NGC 4051 is a member of the Ursa Major Cluster. Its peculiar velocity is −490 ± 34 km/s, consistent with the rest of the cluster. It is a member of the NGC 4111 Group, which is part of the Ursa Major Cloud and is the second largest group in the cloud after the NGC 3992 Group. Supernovae Three supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parsec
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 is defined as the distance at which 1 AU subtended angle, subtends an angle of one arcsecond ( of a degree (angle), degree). The nearest star, Proxima Centauri, is about from the Sun: from that distance, the gap between the Earth and the Sun spans slightly less than one arcsecond. Most Naked-eye stars, stars visible to the naked eye are within a few hundred parsecs of the Sun, with the most distant at a few thousand parsecs, and the Andromeda Galaxy at over 700,000 parsecs. The word ''parsec'' is a shortened form of ''a distance corresponding to a parallax of one second'', coined by the British astronomer Herbert Hall Turner in 1913. The unit was introduced to simplify the calculation of astronomical distances from raw observational data. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-year
A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Despite its inclusion of the word "year", the term should not be misinterpreted as a unit of time. The ''light-year'' is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist contexts and popular science publications. The unit most commonly used in professional astronomy is the parsec (symbol: pc, about 3.26 light-years). Definitions As defined by the International Astronomical Union (IAU), the light-year is the product of the Julian year (365.25 days, as opposed to the 365.2425-day Gregorian year or the 365.24219-day Tropical year that both approxim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virgo Cluster
The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the Virgo constellation. Comprising approximately 1,300 (and possibly up to 2,000) member galaxies, the cluster forms the heart of the larger Virgo Supercluster, of which the Local Group (containing the Milky Way galaxy) is a member. The Local Group actually experiences the mass of the Virgo Supercluster as the Virgocentric flow. It is estimated that the Virgo Cluster's mass is 1.2 out to 8 degrees of the cluster's center or a radius of about 2.2 Mpc. Many of the brighter galaxies in this cluster, including the giant elliptical galaxy Messier 87, were discovered in the late 1770s and early 1780s and subsequently included in Charles Messier's catalogue of non-cometary fuzzy objects. Described by Messier as nebulae without stars, their true nature was not recognized until the 1920s. The cluster extends across approximately 8 degrees centered in the constellation Virgo. Some of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
