Seyfert galaxy
Seyfert galaxies are spiral or irregular galaxies containing an extremely bright nucleus, most likely caused by a supermassive black hole, that can sometimes outshine the surrounding galaxy.
Seyfert Galaxy :
A Seyfert galaxy is any of a class of galaxies known to have active nuclei. Such galaxies were named for the American astronomer Carl K. Seyfert, who first called attention to them in 1944.
Seyfert 2 Galaxy
Active galaxies which are brightest at infrared wavelengths. They show narrow lines and appear to be cool and dusty.
Active Galactic Nucleus, Seyfert 1 Galaxy ...
Seyfert's Sextet
Colliding Galaxies
Y'know, if you login, you can write something here. You can also Create a New User if you don't already have an account.
Definition: Seyfert galaxy: A spiral galaxy whose nucleus shows bright emission lines; one of a class of galaxies first described by C. Seyfert.
Space Tragedies9 Planets in Nine DaysAstronomy 101
Related Articles ...
Seyfert galaxy
Wikipedia, the free encyclopedia - Cite This Source ...
Seyfert galaxies are, almost by definition, mostly in spirals and S0s (Simkin et al 1980 ApJ 237, 404; Heckman 1980 PASP 90, 241; Adams 1977 ApJSuppl 33, 19). Companions and distortions are often present (see p. 83).
Seyfert Galaxies
Seyfert galaxies are lower-luminosity active galactic nuclei, with MB -21.
Seyfert's Sextet (NGC6027) in Serpens
(RA 15h 59.2m , Dec. +20°45', 15 mag., 2 x 1 arcmin.)
This compact group of interacting galaxies is located 1°50' E of r Serpentis (see finder chart below).
Seyfert galaxy Type of active galaxy whose emission comes from a very small region within the nucleus of an otherwise normal-looking sprial system.
SEYFERT GALAXY
A Seyfert galaxy is an active spiral galaxy. Its nucleus (center) has bright emission lines, including visible wavelengths. The brightness varies over relatively short time periods (less than a year).
Seyfert galaxies are the next strange beasts in the astronomical zoo. There are actually two types of these. Like BL Lac, Seyferts show very abnormally bright cores. However, unlike BL Lac galaxies, these have emission lines (hurray!).
Seyfert Galaxy
(a) A type of spiral galaxy first discovered by Karl Seyfert in the 1940s. The central region of a Seyfert galaxy is distinguished by powerful radiation, much of it focused into narrow frequencies.
Seyfert Galaxy: A galaxy that appears to be a normal spiral galaxy, but whose core fluctuates in brightness. It is believed that these fluctuations are caused by powerful eruptions in the core of the galaxy.
Seyfert galaxy- a galaxy that has a small, bright nucleus and faint spiral arms; it is often a strong radio source
Shepherd moon- a satellite which constrains the extent of a planetary ring through gravitational forces ...
Seyfert galaxy
A spiral galaxy whose nucleus shows bright emission lines; one of a class of galaxies first described by C. Seyfert.
Seyfert Galaxy
An otherwise normal spiral galaxy with an unusually bright, small core that fluctuates in brightness; believed to indicate the core is erupting.
Shear (S) Waves ...
Seyfert Galaxy
a main-sequence star which rotates rapidly, causing a loss of matter to an ever-expanding shell.
Shield volcano
a volcano in the shape of a flattened dome, broad and low, built by flows of very fluid lava.
Seyfert galaxies. A kind of so-called 'active' galaxy. Seyfert galaxies have fairly small but bright nuclei and weak spiral arms. These galaxies are also strong emitters of radio wave energy.
Seyfert Galaxy - A barred or normal spiral galaxy with a small, very bright nucleus
SETI - The search for extraterrestrial intelligence ...
Seyferts
Consider NGC 4151, a spiral galaxy 15 Mpc away. Photographs by Carl Seyfert in the 1940s showed a very bright point-like nucleus.
Seyfert 2 galaxy NGC 7742
Credit: AURA/STScI/NASA
As well as Seyferts, other galaxies are also classified as AGN. These include radio galaxies, quasars, blazars and LINERs.
Seyfert galaxy - (n.)
A type of spiral galaxy that has a bright nucleus and whose spectrum shows emission lines.
Seyfert galaxy Type of active galaxy that exhibits intense energetic activity from a small region within the nucleus of an otherwise normal-looking spiral galaxy.
Seyfert Galaxy
A galaxy characterized by a moderately bright, compact active galactic nucleus, presumably powered by a black hole.
Shock Wave ...
Seyfert galaxies
Galaxies with small bright centers. Many Seyfert galaxies are good sources of radio waves.
Shooting star ...
Seyfert's Sextet is an example of a compact galaxy group.
Most galaxies in the universe are gravitationally bound to a number of other galaxies.
Seyfert Galaxy: Seyferts are spirals galaxies that have bright starlike cores. Seyferts have strong emission lines, and the emission lines are very broad, implying velocities from 500 to 4000 km/sec.
The Seyfert galaxy NGC 1566.
The energy of Seyfert galaxy nuclei fluctuates quickly like the quasar fluctuations, so the energy generator must be quite small.
Galaxia Seyfert, NGC 1566. (Cortesía del Observatorio Anglo-Australiano/Observatorio Real de Edimburgo)
(69K GIF)
Galaxia espiral Barred, NGC 1365. (Cortesía del Observatorio Anglo-Australiano/Observatorio Real de Edimburgo)
(97K GIF) ...
Carl K. Seyfert
1911-1960
American
discovered the first active galaxy, part of a group now called Seyfert galaxies ...
1943 - Carl Keenan Seyfert identifies six spiral galaxies with unusually broad emission lines, named Seyfert galaxies,
1949 - J.G. Bolton, G.J. Stanley, and O.B. Slee identify NGC 4486 (M87) and NGC 5128 as extragalactic radio sources, ...
The Laws List The Barnard-Seyfert Astronomical Society Resources from the Nashville, Tennessee astronomical organization.
AGN are found at the heart of active galaxies, including quasars, Seyfert galaxies, blazars, and radio galaxies. In addition to their great energy output, they can be highly variable.
Astronomers classify NGC 4945 as a Seyfert galaxy, after Ameriacn astronomer Carl Seyfert, who first identified this family of galaxies - a subclass of active galactic nuclei - to have curious light signatures emanating from their central engines.
NGC 1808 is a Seyfert galaxy, a barred spiral galaxy with notable similarities to the Milky Way, approximately 40 million light-years distant.
M77 (NGC 1068) is a small spiral galaxy seen face on, one of the so-called Seyfert gallaxies, which means it has a radio source - a feeble example of a quasar.
M77 is about 50 million light years away, and is found one degree SE of delta Ceti.
The Seyfert galaxy in Dorado, NGC 1566
UKS 14. The Large Magellanic Cloud
UKS 15. The 30 Doradus nebula in the LMC
UKS 16. Star clouds north of the the Large Magellanic Cloud
UKS 27. Henize 44 (NGC 1929-37), LMC nebula
UKS 28.
Double stars alpha Cet, gamma Cet
Variable stars omicron Cet
Nearby star tau Cet
Spiralgalaxy M 77 (Seyfert-Galaxy), NGC 247
Planetary nebula NGC 246
Meteor Showers: October Cetids, Eta Cetids, Omicron Cetids ...
active galaxies
Energetic galaxies that release huge amounts of energy, mostly in the form of long-wavelength radiation. The two most common types are Seyfert galaxies and Radio galaxies.
Gamma rays from outside the Milky Way have been found emanating from radio galaxies (galaxies whose radio emissions constitute an extraordinarily large amount of their total energy output), Seyfert galaxies (galaxies with extremely bright ...
These may range in mass from about 106 to 109 solar masses. Such supermassive black holes are likely to be responsible for phenomena such as active galactic nuclei (AGNs), Seyfert galaxies, BL Lacerate Objects and quasars or QSOs.
Active galactic nuclei are believed to contain supermassive black holes that power the nonstellar phenomena associated with active galaxies. Examples of active galaxies include: Seyfert galaxies, Radio galaxies (image), and BL Lac objects.
 See also: Galaxy, Galaxies, Light, Black Hole, Quasar
|
