26 relations: Amateur astronomy, Apparent magnitude, Brady Haran, Charles Messier, Constellation, Epoch (astronomy), Equator, Eskimo Nebula, European Southern Observatory, Helix Nebula, Light-year, List of Messier objects, List of planetary nebulae, Messier object, Minute and second of arc, New General Catalogue, Photoionization, Planetary nebula, Radius, Semi-minor axis, Spheroid, Spitzer Space Telescope, The Astronomical Journal, Vulpecula, White dwarf, 10 exametres.
Amateur astronomy is a hobby whose participants enjoy watching the sky, and the abundance of objects found in it with the unaided eye, binoculars, or telescopes.
The apparent magnitude (m) of a celestial object is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere.
Brady John Haran (born 18 June 1976) is an Australian independent film-maker and video journalist who is known for his educational videos and documentary films produced for BBC News and for his YouTube channels, such as Numberphile and Periodic Videos.
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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!!: Dumbbell Nebula and Charles Messier ·
In modern astronomy, a constellation is a specific area of the celestial sphere as defined by the International Astronomical Union (IAU).
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In astronomy, an epoch is a moment in time used as a reference point for some time-varying astronomical quantity, such as the celestial coordinates or elliptical orbital elements of a celestial body, because these are subject to perturbations and vary with time.
An equator is the intersection of a sphere's surface with the plane perpendicular to the sphere's axis of rotation and midway between the poles.
New!!: Dumbbell Nebula and Equator ·
The Eskimo Nebula (NGC 2392), also known as the Clownface Nebula or Caldwell 39, is a bipolar double-shell planetary nebula (PN).
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The European Southern Observatory (ESO, formally: European Organisation for Astronomical Research in the Southern Hemisphere; Observatoire européen austral) is a 16-nation intergovernmental research organisation for astronomy.
The Helix Nebula, also known as The Helix, NGC 7293, is a large planetary nebula (PN) located in the constellation Aquarius.
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A light-year (abbreviation: ly), sometimes written light year, is a unit of length used informally to express astronomical distances.
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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").
The following is an incomplete list of known planetary nebulae.
The Messier objects are a set of over 100 astronomical objects first listed by French astronomer Charles Messier in 1771.
New!!: Dumbbell Nebula and Messier object ·
A minute of arc (MOA), arcminute (arcmin) or minute arc is a unit of angular measurement equal to one-sixtieth of one degree.
The New General Catalogue of Nebulae and Clusters of Stars (abbreviated as NGC) is a well-known catalogue of deep-sky objects in astronomy compiled by John Louis Emil Dreyer in 1888, as a new version of John Herschel's Catalogue of Nebulae and Clusters of Stars.
Photoionization is the physical process in which an ion is formed from the interaction of a photon with an atom or molecule.
New!!: Dumbbell Nebula and Photoionization ·
A planetary nebula, often abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding glowing shell of ionized gas ejected from old red giant stars late in their lives.
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In classical geometry, the radius of a circle or sphere is the length of a line segment from its center to its perimeter.
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In geometry, the semi-minor axis (also semiminor axis) is a line segment associated with most conic sections (that is, with ellipses and hyperbolas) that is at right angles with the semi-major axis and has one end at the center of the conic section.
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A spheroid, or ellipsoid of revolution, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters.
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The Spitzer Space Telescope (SST), formerly the Space Infrared Telescope Facility (SIRTF), is an infrared space observatory launched in 2003.
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.
Vulpecula is a faint constellation in the northern sky.
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A white dwarf, also called a degenerate dwarf, is a stellar remnant composed mostly of electron-degenerate matter.
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To help compare different orders of magnitude, this page lists distances starting at 10 Em (1019 m or 1,100 light years).
New!!: Dumbbell Nebula and 10 exametres ·