Get it on Google Play
New! Download Unionpedia on your Android™ device!
Faster access than browser!

Messier 81

Index Messier 81

Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a spiral galaxy about 12 million light-years away, in the constellation Ursa Major. [1]

60 relations: Active galactic nucleus, Alpha Ursae Majoris, Amateur astronomy, Andromeda Galaxy, Aperture, Astronomer, Binoculars, Cambridge University Press, Central Bureau for Astronomical Telegrams, Charles Messier, Constellation, Cosmic dust, Earth, Galaxies in fiction, Galaxy group, Helium, Hydrogen, IAU Circular, Interacting galaxy, Interstellar medium, Johann Elert Bode, Light-year, List of galaxies, List of Messier objects, Local Group, Low-ionization nuclear emission-line region, M81 Group, Messier 82, Messier object, Micrometre, Milky Way, Minute and second of arc, Morphological Catalogue of Galaxies, Nature (journal), New General Catalogue, NGC 3077, Nova, Orders of magnitude (length), Parsec, Pierre Méchain, Polycyclic aromatic hydrocarbon, Principal Galaxies Catalogue, SN 1993J, Spain, Spectral line, Spiral galaxy, Spitzer Space Telescope, Star formation, Starburst galaxy, Stellar classification, ..., Supermassive black hole, Supernova, Telescope, The Astronomical Journal, The Astrophysical Journal, Triangulum Galaxy, Type II supernova, Uppsala General Catalogue, Ursa Major, Virgo Supercluster. Expand index (10 more) »

Active galactic nucleus

An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much higher than normal luminosity over at least some portion—and possibly all—of the electromagnetic spectrum, with characteristics indicating that the excess luminosity is not produced by stars.

New!!: Messier 81 and Active galactic nucleus · See more »

Alpha Ursae Majoris

Alpha Ursae Majoris (α Ursae Majoris, abbreviated Alpha UMa, α UMa), also named Dubhe, is (despite being designated 'alpha') the second-brightest star in the constellation of Ursa Major.

New!!: Messier 81 and Alpha Ursae Majoris · See more »

Amateur astronomy

Amateur astronomy is a hobby whose participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes.

New!!: Messier 81 and Amateur astronomy · See more »

Andromeda Galaxy

The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way.

New!!: Messier 81 and Andromeda Galaxy · See more »


In optics, an aperture is a hole or an opening through which light travels.

New!!: Messier 81 and Aperture · See more »


An astronomer is a scientist in the field of astronomy who concentrates their studies on a specific question or field outside the scope of Earth.

New!!: Messier 81 and Astronomer · See more »


Binoculars or field glasses are two telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects.

New!!: Messier 81 and Binoculars · See more »

Cambridge University Press

Cambridge University Press (CUP) is the publishing business of the University of Cambridge.

New!!: Messier 81 and Cambridge University Press · See more »

Central Bureau for Astronomical Telegrams

The Central Bureau for Astronomical Telegrams (CBAT) is the official international clearing house for information relating to transient astronomical events.

New!!: Messier 81 and Central Bureau for Astronomical Telegrams · See more »

Charles Messier

Charles Messier (26 June 1730 – 12 April 1817) was a French astronomer most notable for publishing an astronomical catalogue consisting of nebulae and star clusters that came to be known as the 110 "Messier objects".

New!!: Messier 81 and Charles Messier · See more »


A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.

New!!: Messier 81 and Constellation · See more »

Cosmic dust

Cosmic dust, also called extraterrestrial dust or space dust, is dust which exists in outer space, as well as all over planet Earth.

New!!: Messier 81 and Cosmic dust · See more »


Earth is the third planet from the Sun and the only astronomical object known to harbor life.

New!!: Messier 81 and Earth · See more »

Galaxies in fiction

Galaxies other than the Milky Way are popular settings for creators of science fiction, particularly those working with broad-scale space opera settings.

New!!: Messier 81 and Galaxies in fiction · See more »

Galaxy group

A galaxy group or group of galaxies (GrG) is an aggregation of galaxies comprising about 50 or fewer gravitationally bound members, each at least as luminous as the Milky Way (about 1010 times the luminosity of the Sun); collections of galaxies larger than groups that are first-order clustering are called galaxy clusters.

New!!: Messier 81 and Galaxy group · See more »


Helium (from lit) is a chemical element with symbol He and atomic number 2.

New!!: Messier 81 and Helium · See more »


Hydrogen is a chemical element with symbol H and atomic number 1.

New!!: Messier 81 and Hydrogen · See more »

IAU Circular

The International Astronomical Union Circulars (IAUCs) are notices that give information about astronomical phenomena.

New!!: Messier 81 and IAU Circular · See more »

Interacting galaxy

Interacting galaxies (colliding galaxies) are galaxies whose gravitational fields result in a disturbance of one another.

New!!: Messier 81 and Interacting galaxy · See more »

Interstellar medium

In astronomy, the interstellar medium (ISM) is the matter and radiation that exists in the space between the star systems in a galaxy.

New!!: Messier 81 and Interstellar medium · See more »

Johann Elert Bode

Johann Elert Bode (19 January 1747 – 23 November 1826) was a German astronomer known for his reformulation and popularisation of the Titius–Bode law.

New!!: Messier 81 and Johann Elert Bode · See more »


The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.

New!!: Messier 81 and Light-year · See more »

List of galaxies

The following is a list of notable galaxies.

New!!: Messier 81 and List of galaxies · See more »

List of Messier objects

The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his "Catalogue des Nébuleuses et des Amas d'Étoiles" ("Catalogue of Nebulae and Star Clusters").

New!!: Messier 81 and List of Messier objects · See more »

Local Group

The Local Group is the galaxy group that includes the Milky Way.

New!!: Messier 81 and Local Group · See more »

Low-ionization nuclear emission-line region

A low-ionization nuclear emission-line region (LINER) is a type of galactic nucleus that is defined by its spectral line emission.

New!!: Messier 81 and Low-ionization nuclear emission-line region · See more »

M81 Group

The M81 Group is a galaxy group in the constellations Ursa Major and Camelopardalis that includes the galaxies Messier 81 and Messier 82, as well as several other galaxies with high apparent brightnesses.

New!!: Messier 81 and M81 Group · See more »

Messier 82

Messier 82 (also known as NGC 3034, Cigar Galaxy or M82) is a starburst galaxy approximately 12 million light-years away in the constellation Ursa Major.

New!!: Messier 81 and Messier 82 · See more »

Messier object

The Messier objects are a set of 110 astronomical objects, of which 103 were included in lists published by French astronomer Charles Messier in 1771 and 1781.

New!!: Messier 81 and Messier object · See more »


The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is an SI derived unit of length equaling (SI standard prefix "micro-".

New!!: Messier 81 and Micrometre · See more »

Milky Way

The Milky Way is the galaxy that contains our Solar System.

New!!: Messier 81 and Milky Way · See more »

Minute and second of arc

A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.

New!!: Messier 81 and Minute and second of arc · See more »

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.

New!!: Messier 81 and Morphological Catalogue of Galaxies · See more »

Nature (journal)

Nature is a British multidisciplinary scientific journal, first published on 4 November 1869.

New!!: Messier 81 and Nature (journal) · See more »

New General Catalogue

The New General Catalogue of Nebulae and Clusters of Stars (abbreviated as NGC) is a catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888.

New!!: Messier 81 and New General Catalogue · See more »

NGC 3077

NGC 3077 is a small galaxy, a member of the M81 Group, which is located in the northern constellation Ursa Major.

New!!: Messier 81 and NGC 3077 · See more »


A nova (plural novae or novas) or classical nova (CN, plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months.

New!!: Messier 81 and Nova · See more »

Orders of magnitude (length)

The following are examples of orders of magnitude for different lengths.

New!!: Messier 81 and Orders of magnitude (length) · See more »


The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System.

New!!: Messier 81 and Parsec · See more »

Pierre Méchain

Pierre François André Méchain (16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep sky objects and comets.

New!!: Messier 81 and Pierre Méchain · See more »

Polycyclic aromatic hydrocarbon

Polycyclic aromatic hydrocarbons (PAHs, also polyaromatic hydrocarbons or polynuclear aromatic hydrocarbons) are hydrocarbons—organic compounds containing only carbon and hydrogen—that are composed of multiple aromatic rings (organic rings in which the electrons are delocalized).

New!!: Messier 81 and Polycyclic aromatic hydrocarbon · See more »

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.

New!!: Messier 81 and Principal Galaxies Catalogue · See more »

SN 1993J

SN 1993J is a supernova observed in the galaxy M81.

New!!: Messier 81 and SN 1993J · See more »


Spain (España), officially the Kingdom of Spain (Reino de España), is a sovereign state mostly located on the Iberian Peninsula in Europe.

New!!: Messier 81 and Spain · See more »

Spectral line

A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.

New!!: Messier 81 and Spectral line · See more »

Spiral galaxy

Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae(pp. 124–151) and, as such, form part of the Hubble sequence.

New!!: Messier 81 and Spiral galaxy · See more »

Spitzer Space Telescope

The Spitzer Space Telescope (SST), formerly the Space Infrared Telescope Facility (SIRTF), is an infrared space telescope launched in 2003 and still operating as of 2018.

New!!: Messier 81 and Spitzer Space Telescope · See more »

Star formation

Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as "stellar nurseries" or "star-forming regions", collapse and form stars.

New!!: Messier 81 and Star formation · See more »

Starburst galaxy

A starburst galaxy is a galaxy undergoing an exceptionally high rate of star formation, as compared to the long-term average rate of star formation in the galaxy or the star formation rate observed in most other galaxies.

New!!: Messier 81 and Starburst galaxy · See more »

Stellar classification

In astronomy, stellar classification is the classification of stars based on their spectral characteristics.

New!!: Messier 81 and Stellar classification · See more »

Supermassive black hole

A supermassive black hole (SMBH or SBH) is the largest type of black hole, on the order of hundreds of thousands to billions of solar masses, and is found in the centre of almost all currently known massive galaxies.

New!!: Messier 81 and Supermassive black hole · See more »


A supernova (plural: supernovae or supernovas, abbreviations: SN and SNe) is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion.

New!!: Messier 81 and Supernova · See more »


A telescope is an optical instrument that aids in the observation of remote objects by collecting electromagnetic radiation (such as visible light).

New!!: Messier 81 and Telescope · See more »

The Astronomical Journal

The Astronomical Journal (often abbreviated AJ in scientific papers and references) is a peer-reviewed monthly scientific journal owned by the American Astronomical Society and currently published by IOP Publishing.

New!!: Messier 81 and The Astronomical Journal · See more »

The Astrophysical Journal

The Astrophysical Journal, often abbreviated ApJ (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler.

New!!: Messier 81 and The Astrophysical Journal · See more »

Triangulum Galaxy

The Triangulum Galaxy is a spiral galaxy approximately 3 million light-years (ly) from Earth in the constellation Triangulum.

New!!: Messier 81 and Triangulum Galaxy · See more »

Type II supernova

A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star.

New!!: Messier 81 and Type II supernova · See more »

Uppsala General Catalogue

The Uppsala General Catalogue of Galaxies (UGC) is a catalogue of 12,921 galaxies visible from the northern hemisphere.

New!!: Messier 81 and Uppsala General Catalogue · See more »

Ursa Major

Ursa Major (also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory.

New!!: Messier 81 and Ursa Major · See more »

Virgo Supercluster

The Virgo Supercluster (Virgo SC) or the Local Supercluster (LSC or LS) is a mass concentration of galaxies containing the Virgo Cluster and Local Group, which in turn contains the Milky Way and Andromeda galaxies.

New!!: Messier 81 and Virgo Supercluster · See more »

Redirects here:

Bode Galaxy, Bode's Galaxy, Bode's Nebula, Bodes Galaxy, M 81, Messier Object 81, NGC 3031, NGC3031, PGC 28630, Spiral Galaxy M81.


[1] https://en.wikipedia.org/wiki/Messier_81

Hey! We are on Facebook now! »