text:
Main sequence
From Wikipedia, the free encyclopedia
Jump to: navigation, search
For the racehorse, see Main Sequence (horse).
A Hertzsprung–Russell diagram plots the actual brightness (or absolute magnitude) of a star against its color index (represented as B−V). The main sequence is visible as a prominent diagonal band that runs from the upper left to the lower right. This plot shows 22,000 stars from the Hipparcos Catalogue together with 1,000 low-luminosity stars (red and white dwarfs) from the Gliese Catalogue of Nearby Stars.
Star formation
Object classes
Interstellar medium
Molecular cloud
Bok globule
Dark nebula
Young stellar object
Protostar
T Tauri star
Pre-main-sequence star
Herbig Ae/Be star
Herbig–Haro object
Theoretical concepts
Accretion
Initial mass function
Jeans instability
Kelvin–Helmholtz mechanism
Nebular hypothesis
Planetary migration
Star portal
v
t
e
In astronomy, the main sequence is a continuous and distinctive band of stars that appear on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or dwarf stars.[1][2] These are the most numerous true stars in the universe, and include the Earth's Sun.
After condensation of mass and ignition of a star, it generates thermal energy in the dense core region through nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.
The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (1.5 M☉) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases. Main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.
In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage.[3] More massive stars can explode as a supernova,[4] or collapse directly into a black hole.
In April, 2018, astronomers reported the detection of the most distant "ordinary" (i.e., main sequence) star, named Icarus (formally, MACS J1149 Lensed Star 1), at 9 billion light-years away from Earth.[5][6]
Contents
[hide]
1 History
2 Formation and evolution
3 Properties
4 Dwarf terminology
5 Parameters
5.1 Sample parameters
6 Energy generation
7 Structure
8 Luminosity-color variation
9 Lifetime
10 Evolutionary tracks
11 See also
12 Notes
13 References
14 Further reading
14.1 General
14.2 Technical
History[edit]
Hot and brilliant O-type main-sequence stars in star-forming regions. These are all regions of star formation that contain many hot young stars including several bright stars of spectral type O.[7]
In the early part of the 20th century, information about the types and distances of stars became more readily available. The spectra of stars were shown to have distinctive features, which allowed them to be categorized. Annie Jump Cannon and Edward C. Pickering at Harvard College Observatory developed a method of categorization that became known as the Harvard Classification Scheme, published in the Harvard Annals in 1901.[8]
In Potsdam in 1906, the Danish astronomer Ejnar Hertzsprung noticed that the reddest stars—classified as K and M in the Harvard scheme—could be divided into two distinct groups. These stars are either much brighter than the Sun, or much fainter. To distinguish these groups, he called them "giant" and "dwarf" stars. The following year he began studying star clusters; large groupings of stars that are co-located at approximately the same distance. He published the first plots of color versus luminosity for these stars. These plots showed a prominent and continuous sequence of stars, which he named the Main Sequence.[9]
At Princeton University, Henry Norris Russell was following a similar course of research. He was studying the relationship between the spectral classification of stars and their actual brightness as corrected for distance—their absolute magnitude. For this purpose he used a set of stars that had reliable parallaxes and many of which had been categorized at Harvard. When he plotted the spectral types of these stars against their absolute magnitude, he found that dwarf stars followed a distinct relationship. This allowed the real brightness of a dwarf star to be predicted with reasonable accuracy.[10]
Of the red stars observed by Hertzsprung, the dwarf stars also followed the spectra-luminosity relationship discovered by Russell. However, the giant stars are much brighter than dwarfs and so do not follow the same relationship. Russell proposed that the "giant stars must have low density or great surface-brightness, and the reverse is true of dwarf stars". The same curve also showed that there were very few faint white stars.[10]
In 1933, Bengt Strömgren introduced the term Hertzsprung–Russell diagram to denote a luminosity-spectral class diagram.[11] This name reflected the parallel development of this technique by both Hertzsprung and Russell earlier in the century.[9]
As evolutionary models of stars were developed during the 1930s, it was shown that, for stars of a uniform chemical composition, a relationship exists between a star's mass and its luminosity and radius. That is, for a given mass and composition, there is a unique solution for determining the star's radius and luminosity. This became known as the Vogt-Russell theorem; named after Heinrich Vogt and Henry Norris Russell. By this theorem, when a star's chemical composition and its position on the main sequence is known, so too is the star's mass and radius. (However, it was subsequently discovered that the theorem breaks down somewhat for stars of non-uniform composition.)[12]
A refined scheme for stellar classification was published in 1943 by William Wilson Morgan and Philip Childs Keenan.[13] The MK classification assigned each star a spectral type—based on the Harvard classification—and a luminosity class. The Harvard classification had been developed by assigning a different letter to each star based on the strength of the hydrogen spectral line, before the relationship between spectra and temperature was known. When ordered by temperature and when duplicate classes were removed, the spectral types of stars followed, in order of decreasing temperature with colors ranging from blue to red, the sequence O, B, A, F, G, K and M. (A popular mnemonic for memorizing this sequence of stellar classes is "Oh Be A Fine Girl/Guy, Kiss Me".) The luminosity class ranged from I to V, in order of decreasing luminosity. Stars of luminosity class V belonged to the main sequence.[14]
In April, 2018, astronomers reported the detection of the most distant "ordinary" (i.e., main sequence) star, named Icarus (formally, MACS J1149 Lensed Star 1), at 9 billion light-years away from Earth.[5][6]
Formation and evolution[edit]
Main articles: Star formation, Protostar, Pre-main-sequence star, and Stellar evolution § Main sequence
When a protostar is formed from the collapse of a giant molecular cloud of gas and dust in the local interstellar medium, the initial composition is homogeneous throughout, consisting of about 70% hydrogen, 28% helium and trace amounts of other elements, by mass.[15] The initial mass of the star depends on the local conditions within the cloud. (The mass distribution of newly formed stars is described empirically by the initial mass function.)[16] During the initial collapse, this pre-main-sequence star generates energy through gravitational contraction. Upon reaching a suitable density, energy generation is begun at the core using an exothermic nuclear fusion process that converts hydrogen into helium.[14]
Hertzsprung–Russell diagram
Spectral type
Brown dwarfs
White dwarfs
Red dwarfs
Subdwarfs
Main sequence
("dwarfs")
Subgiants
Giants
Bright giants
Supergiants
Hypergiants
absolute
magni-
tude
(MV)
When nuclear fusion of hydrogen becomes the dominant energy production process and the excess energy gained from gravitational contraction has been lost,[17] the star lies along a curve on the Hertzsprung–Russell diagram (or HR diagram) called the standard main sequence. Astronomers will sometimes refer to this stage as "zero age main sequence", or ZAMS.[18][19] The ZAMS curve can be calculated using computer models of stellar properties at the point when stars begin hydrogen fusion. From this point, the brightness and surface temperature of stars typically increase with age.[20]
A star remains near its initial position on the main sequence until a significant amount of hydrogen in the core has been consumed, then begins to evolve into a more luminous star. (On the HR diagram, the evolving star moves up and to the right of the main sequence.) Thus the main sequence represents the primary hydrogen-burning stage of a star's lifetime.[14]
Properties[edit]
The majority of stars on a typical HR diagram lie along the main-sequence curve. This line is pronounced because both the spectral type and the luminosity depend only on a star's mass, at least to zeroth-order approximation, as long as it is fusing hydrogen at its core—and that is what almost all stars spend most of their "active" lives doing.[21]
The temperature of a star determines its spectral type via its effect on the physical properties of plasma in its photosphere. A star's energy emission as a function of wavelength is influenced by both its temperature and composition. A key indicator of this energy distribution is given by the color index, B − V, which measures the star's magnitude in blue (B) and green-yellow (V) light by means of filters.[note 1] This difference in magnitude provides a measure of a star's temperature.
Dwarf terminology[edit]
Main-sequence stars are called dwarf stars, but this terminology is partly historical and can be somewhat confusing. For the cooler stars, dwarfs such as red dwarfs, orange dwarfs, and yellow dwarfs are indeed much smaller and dimmer than other stars of those colors. However, for hotter blue and white stars, the size and brightness difference between so-called "dwarf" stars that are on the main sequence and the so-called "giant" stars that are not becomes smaller; for the hottest stars it is not directly observable. For those stars the terms "dwarf" and "giant" refer to differences in spectral lines which indicate if a star is on the main sequence or off it. Nevertheless, very hot main-sequence stars are still sometimes called dwarfs, even though they have roughly the same size and brightness as the "giant" stars of that temperature.[22]
The common use of "dwarf" to mean main sequence is confusing in another way, because there are dwarf stars which are not main-sequence stars. For example, a white dwarf is the dead core of a star that is left after the star has shed its outer layers, that is much smaller than a main-sequence star, roughly the size of Earth. These represent the final evolutionary stage of many main-sequence stars.[23]
Parameters[edit]
Comparison of main sequence stars of each spectral class
By treating the star as an idealized energy radiator known as a black body, the luminosity L and radius R can be related to the effective temperature Teff by the Stefan–Boltzmann law:
L = 4 π σ R 2 T e f f 4 {\displaystyle L=4\pi \sigma R^{2}T_{eff}^{4}}
where σ is the Stefan–Boltzmann constant. As the position of a star on the HR diagram shows its approximate luminosity, this relation can be used to estimate its radius.[24]
The mass, radius and luminosity of a star are closely interlinked, and their respective values can be approximated by three relations. First is the Stefan–Boltzmann law, which relates the luminosity L, the radius R and the surface temperature Teff. Second is the mass–luminosity relation, which relates the luminosity L and the mass M. Finally, the relationship between M and R is close to linear. The ratio of M to R increases by a factor of only three over 2.5 orders of magnitude of M. This relation is roughly proportional to the star's inner temperature TI, and its extremely slow increase reflects the fact that the rate of energy generation in the core strongly depends on this temperature, whereas it has to fit the mass–luminosity relation. Thus, a too high or too low temperature will result in stellar instability.
A better approximation is to take ε = L/M, the energy generation rate per unit mass, as ε is proportional to TI15, where TI is the core temperature. This is suitable for stars at least as massive as the Sun, exhibiting the CNO cycle, and gives the better fit R ∝ M0.78.[25]
Sample parameters[edit]
The table below shows typical values for stars along the main sequence. The values of luminosity (L), radius (R) and mass (M) are relative to the Sun—a dwarf star with a spectral classification of G2 V. The actual values for a star may vary by as much as 20–30% from the values listed below.[26]
Table of main-sequence stellar parameters[27]
Stellar
Class
Radius
Mass
Luminosity
Temp.
Examples[28]
R/R☉
M/M☉
L/L☉
K
O6 18 40 500,000 38,000 Theta1 Orionis C
B0 07.4 18 020,000 30,000 Phi1 Orionis
B5 03.8 06.5 000,800 16,400 Pi Andromedae A
A0 02.5 03.2 000,080 10,800 Alpha Coronae Borealis A
A5 01.7 02.1 000,020 08,620 Beta Pictoris
F0 01.3 01.7 000,006 07,240 Gamma Virginis
F5 01.2 01.3 000,002.5 06,540 Eta Arietis
G0 01.05 01.10 000,001.26 05,920 Beta Comae Berenices
G2 01.00 01.00 000,001.00 05,780 Sun[note 2]
G5 00.93 00.93 000,000.79 05,610 Alpha Mensae
K0 00.85 00.78 000,000.40 05,240 70 Ophiuchi A
K5 00.74 00.69 000,000.16 04,410 61 Cygni A[29]
M0 00.63 00.47 000,000.063 03,920 Gliese 185[30]
M5 00.32 00.21 000,000.0079 03,120 EZ Aquarii A
M8 00.13 00.10 000,000.0008 02,660 Van Biesbroeck's star[31]
Energy generation[edit]
Logarithm of the relative energy output (ε)
Proton-Proton (PP), CNO and Triple-α fusion processes at different temperatures:
The dashed line shows the combined energy generation of the PP and CNO processes within a star. At the Sun's core temperature, the PP process is more efficient.
See also: Stellar nucleosynthesis
All main-sequence stars have a core region where energy is generated by nuclear fusion. The temperature and density of this core are at the levels necessary to sustain the energy production that will support the remainder of the star. A reduction of energy production would cause the overlaying mass to compress the core, resulting in an increase in the fusion rate because of higher temperature and pressure. Likewise an increase in energy production would cause the star to expand, lowering the pressure at the core. Thus the star forms a self-regulating system in hydrostatic equilibrium that is stable over the course of its main sequence lifetime.[32]
Main-sequence stars employ two types of hydrogen fusion processes, and the rate of energy generation from each type depends on the temperature in the core region. Astronomers divide the main sequence into upper and lower parts, based on which of the two is the dominant fusion process. In the lower main sequence, energy is primarily generated as the result of the proton-proton chain, which directly fuses hydrogen together in a series of stages to produce helium.[33] Stars in the upper main sequence have sufficiently high core temperatures to efficiently use the CNO cycle. (See the chart.) This process uses atoms of carbon, nitrogen and oxygen as intermediaries in the process of fusing hydrogen into helium.
At a stellar core temperature of 18 million Kelvin, the PP process and CNO cycle are equally efficient, and each type generates half of the star's net luminosity. As this is the core temperature of a star with about 1.5 M☉, the upper main sequence consists of stars above this mass. Thus, roughly speaking, stars of spectral class F or cooler belong to the lower main sequence, while A-type stars or hotter are upper main-sequence stars.[20] The transition in primary energy production from one form to the other spans a range difference of less than a single solar mass. In the Sun, a one solar-mass star, only 1.5% of the energy is generated by the CNO cycle.[34] By contrast, stars with 1.8 M☉ or above generate almost their entire energy output through the CNO cycle.[35]
The observed upper limit for a main-sequence star is 120–200 M☉.[36] The theoretical explanation for this limit is that stars above this mass can not radiate energy fast enough to remain stable, so any additional mass will be ejected in a series of pulsations until the star reaches a stable limit.[37] The lower limit for sustained proton–proton nuclear fusion is about 0.08 M☉ or 80 times the mass of Jupiter.[33] Below this threshold are sub-stellar objects that can not sustain hydrogen fusion, known as brown dwarfs.[38]
Structure[edit]
Main article: Stellar structure
This diagram shows a cross-section of a Sun-like star, showing the internal structure.
Because there is a temperature difference between the core and the surface, or photosphere, energy is transported outward. The two modes for transporting this energy are radiation and convection. A radiation zone, where energy is transported by radiation, is stable against convection and there is very little mixing of the plasma. By contrast, in a convection zone the energy is transported by bulk movement of plasma, with hotter material rising and cooler material descending. Convection is a more efficient mode for carrying energy than radiation, but it will only occur under conditions that create a steep temperature gradient.[32][39]
In massive stars (above 10 M☉)[40] the rate of energy generation by the CNO cycle is very sensitive to temperature, so the fusion is highly concentrated at the core. Consequently, there is a high temperature gradient in the core region, which results in a convection zone for more efficient energy transport.[33] This mixing of material around the core removes the helium ash from the hydrogen-burning region, allowing more of the hydrogen in the star to be consumed during the main-sequence lifetime. The outer regions of a massive star transport energy by radiation, with little or no convection.[32]
Intermediate-mass stars such as Sirius may transport energy primarily by radiation, with a small core convection region.[41] Medium-sized, low-mass stars like the Sun have a core region that is stable against convection, with a convection zone near the surface that mixes the outer layers. This results in a steady buildup of a helium-rich core, surrounded by a hydrogen-rich outer region. By contrast, cool, very low-mass stars (below 0.4 M☉) are convective throughout.[16] Thus the helium produced at the core is distributed across the star, producing a relatively uniform atmosphere and a proportionately longer main sequence lifespan.[32]
Luminosity-color variation[edit]
The Sun is the most familiar example of a main-sequence star
As non-fusing helium ash accumulates in the core of a main-sequence star, the reduction in the abundance of hydrogen per unit mass results in a gradual lowering of the fusion rate within that mass. Since it is the outflow of fusion-supplied energy that supports the higher layers of the star, the core is compressed, producing higher temperatures and pressures. Both factors increase the rate of fusion thus moving the equilibrium towards a smaller, denser, hotter core producing more energy whose increased outflow pushes the higher layers further out. Thus there is a steady increase in the luminosity and radius of the star over time.[20] For example, the luminosity of the early Sun was only about 70% of its current value.[42] As a star ages this luminosity increase changes its position on the HR diagram. This effect results in a broadening of the main sequence band because stars are observed at random stages in their lifetime. That is, the main sequence band develops a thickness on the HR diagram; it is not simply a narrow line.[43]
Other factors that broaden the main sequence band on the HR diagram include uncertainty in the distance to stars and the presence of unresolved binary stars that can alter the observed stellar parameters. However, even perfect observation would show a fuzzy main sequence because mass is not the only parameter that affects a star's color and luminosity. Variations in chemical composition caused by the initial abundances, the star's evolutionary status,[44] interaction with a close companion,[45] rapid rotation,[46] or a magnetic field can all slightly change a main-sequence star's HR diagram position, to name just a few factors. As an example, there are metal-poor stars (with a very low abundance of elements with higher atomic numbers than helium) that lie just below the main sequence and are known as subdwarfs. These stars are fusing hydrogen in their cores and so they mark the lower edge of main sequence fuzziness caused by variance in chemical composition.[47]
A nearly vertical region of the HR diagram, known as the instability strip, is occupied by pulsating variable stars known as Cepheid variables. These stars vary in magnitude at regular intervals, giving them a pulsating appearance. The strip intersects the upper part of the main sequence in the region of class A and F stars, which are between one and two solar masses. Pulsating stars in this part of the instability strip that intersects the upper part of the main sequence are called Delta Scuti variables. Main-sequence stars in this region experience only small changes in magnitude and so this variation is difficult to detect.[48] Other classes of unstable main-sequence stars, like Beta Cephei variables, are unrelated to this instability strip.
Lifetime[edit]
This plot gives an example of the mass-luminosity relationship for zero-age main-sequence stars. The mass and luminosity are relative to the present-day Sun.
The total amount of energy that a star can generate through nuclear fusion of hydrogen is limited by the amount of hydrogen fuel that can be consumed at the core. For a star in equilibrium, the energy generated at the core must be at least equal to the energy radiated at the surface. Since the luminosity gives the amount of energy radiated per unit time, the total life span can be estimated, to first approximation, as the total energy produced divided by the star's luminosity.[49]
For a star with at least 0.5 M☉, when the hydrogen supply in its core is exhausted and it expands to become a red giant, it can start to fuse helium atoms to form carbon. The energy output of the helium fusion process per unit mass is only about a tenth the energy output of the hydrogen process, and the luminosity of the star increases.[50] This results in a much shorter length of time in this stage compared to the main sequence lifetime. (For example, the Sun is predicted to spend 130 million years burning helium, compared to about 12 billion years burning hydrogen.)[51] Thus, about 90% of the observed stars above 0.5 M☉ will be on the main sequence.[52] On average, main-sequence stars are known to follow an empirical mass-luminosity relationship.[53] The luminosity (L) of the star is roughly proportional to the total mass (M) as the following power law:
L ∝ M 3.5 {\displaystyle {\begin{smallmatrix}L\ \propto \ M^{3.5}\end{smallmatrix}}}
This relationship applies to main-sequence stars in the range 0.1–50 M☉.[54]
The amount of fuel available for nuclear fusion is proportional to the mass of the star. Thus, the lifetime of a star on the main sequence can be estimated by comparing it to solar evolutionary models. The Sun has been a main-sequence star for about 4.5 billion years and it will become a red giant in 6.5 billion years,[55] for a total main sequence lifetime of roughly 1010 years. Hence:[56]
τ M S ≈ 10 10 years ⋅ [ M M ⨀ ] ⋅ [ L ⨀ L ] = 10 10 years ⋅ [ M M ⨀ ] − 2.5 {\displaystyle {\begin{smallmatrix}\tau _{\rm {MS}}\ \approx \ 10^{10}{\text{years}}\cdot \left[{\frac {M}{M_{\bigodot }}}\right]\cdot \left[{\frac {L_{\bigodot }}{L}}\right]\ =\ 10^{10}{\text{years}}\cdot \left[{\frac {M}{M_{\bigodot }}}\right]^{-2.5}\end{smallmatrix}}}
where M and L are the mass and luminosity of the star, respectively, M ⨀ {\displaystyle {\begin{smallmatrix}M_{\bigodot }\end{smallmatrix}}} is a solar mass, L ⨀ {\displaystyle {\begin{smallmatrix}L_{\bigodot }\end{smallmatrix}}} is the solar luminosity and τ M S {\displaystyle \tau _{\rm {MS}}} is the star's estimated main sequence lifetime.
Although more massive stars have more fuel to burn and might intuitively be expected to last longer, they also radiate a proportionately greater amount with increased mass. This is required by the stellar equation of state; for a massive star to maintain equilibrium, the outward pressure of radiated energy generated in the core not only must but will rise to match the titanic inward gravitational pressure of its envelope. Thus, the most massive stars may remain on the main sequence for only a few million years, while stars with less than a tenth of a solar mass may last for over a trillion years.[57]
The exact mass-luminosity relationship depends on how efficiently energy can be transported from the core to the surface. A higher opacity has an insulating effect that retains more energy at the core, so the star does not need to produce as much energy to remain in hydrostatic equilibrium. By contrast, a lower opacity means energy escapes more rapidly and the star must burn more fuel to remain in equilibrium.[58] Note, however, that a sufficiently high opacity can result in energy transport via convection, which changes the conditions needed to remain in equilibrium.[20]
In high-mass main-sequence stars, the opacity is dominated by electron scattering, which is nearly constant with increasing temperature. Thus the luminosity only increases as the cube of the star's mass.[50] For stars below 10 M☉, the opacity becomes dependent on temperature, resulting in the luminosity varying approximately as the fourth power of the star's mass.[54] For very low-mass stars, molecules in the atmosphere also contribute to the opacity. Below about 0.5 M☉, the luminosity of the star varies as the mass to the power of 2.3, producing a flattening of the slope on a graph of mass versus luminosity. Even these refinements are only an approximation, however, and the mass-luminosity relation can vary depending on a star's composition.[16]
Evolutionary tracks[edit]
See also: Stellar evolution
This shows the Hertzsprung–Russell diagrams for two open clusters. NGC 188 (blue) is older, and shows a lower turn off from the main sequence than that seen in M67 (yellow). The dots outside the two sequences are mostly foreground and background stars with no relation to the clusters.
When a main-sequence star consumes the hydrogen at its core, the loss of energy generation causes its gravitational collapse to resume. Stars with less than 0.23 M☉,[3] are predicted to directly become white dwarfs when energy generation by nuclear fusion of hydrogen at their core comes to a halt. In stars between this threshold and 10 M☉, the hydrogen surrounding the helium core reaches sufficient temperature and pressure to undergo fusion, forming a hydrogen-burning shell. In consequence of this change, the outer envelope of the star expands and decreases in temperature, turning it into a red giant. At this point the star is evolving off the main sequence and entering the giant branch. The path which the star now follows across the HR diagram, to the upper right of the main sequence, is called an evolutionary track.
The helium core of a red giant continues to collapse until it is entirely supported by electron degeneracy pressure—a quantum mechanical effect that restricts how closely matter can be compacted. For stars of more than about 0.5 M☉,[59] the core eventually reaches a temperature where it becomes hot enough to burn helium into carbon via the triple alpha process.[60][61] Stars with more than 5–7.5 M☉ can additionally fuse elements with higher atomic numbers.[62][63] For stars with ten or more solar masses, this process can lead to an increasingly dense core that finally collapses, ejecting the star's overlying layers in a Type II supernova explosion,[4] Type Ib supernova or Type Ic supernova.
When a cluster of stars is formed at about the same time, the life span of these stars will depend on their individual masses. The most massive stars will leave the main sequence first, followed steadily in sequence by stars of ever lower masses. Thus the stars will evolve in order of their position on the main sequence, proceeding from the most massive at the left toward the right of the HR diagram. The current position where stars in this cluster are leaving the main sequence is known as the turn-off point. By knowing the main sequence lifespan of stars at this point, it becomes possible to estimate the age of the cluster.[64]
See also[edit]
Star portal
Astronomy portal
Hydrogen-burning process
Red dwarf
Supergiant
Sun
Notes[edit]
Jump up ^ By measuring the difference between these values, this eliminates the need to correct the magnitudes for distance. However, see extinction.
Jump up ^ The Sun is a typical type G2V star.
References[edit]
Jump up ^ Harding E. Smith (1999-04-21). "The Hertzsprung-Russell Diagram". Gene Smith's Astronomy Tutorial. Center for Astrophysics & Space Sciences, University of California, San Diego. Retrieved 2009-10-29.
Jump up ^ Richard Powell (2006). "The Hertzsprung Russell Diagram". An Atlas of the Universe. Retrieved 2009-10-29.
^ Jump up to: a b Adams, Fred C.; Laughlin, Gregory (April 1997). "A Dying Universe: The Long Term Fate and Evolution of Astrophysical Objects". Reviews of Modern Physics. 69 (2): 337–372. arXiv:astro-ph/9701131  . Bibcode:1997RvMP...69..337A. doi:10.1103/RevModPhys.69.337.
^ Jump up to: a b Gilmore, Gerry (2004). "The Short Spectacular Life of a Superstar". Science. 304 (5697): 1915–1916. doi:10.1126/science.1100370. PMID 15218132. Retrieved 2007-05-01.
^ Jump up to: a b Kelly, Patrick L.; et al. (2 April 2018). "Extreme magnification of an individual star at redshift 1.5 by a galaxy-cluster lens". Nature. 2 (4): 334–342. doi:10.1038/s41550-018-0430-3. Retrieved 2 April 2018. CS1 maint: Explicit use of et al. (link)
^ Jump up to: a b Howell, Elizabeth (2 April 2018). "Rare Cosmic Alignment Reveals Most Distant Star Ever Seen". Space.com. Retrieved 2 April 2018.
Jump up ^ "The Brightest Stars Don't Live Alone". ESO Press Release. Retrieved 27 July 2012.
Jump up ^ Longair, Malcolm S. (2006). The Cosmic Century: A History of Astrophysics and Cosmology. Cambridge University Press. pp. 25–26. ISBN 0-521-47436-1.
^ Jump up to: a b Brown, Laurie M.; Pais, Abraham; Pippard, A. B., eds. (1995). Twentieth Century Physics. Bristol; New York: Institute of Physics, American Institute of Physics. p. 1696. ISBN 0-7503-0310-7. OCLC 33102501.
^ Jump up to: a b Russell, H. N. (1913). ""Giant" and "dwarf" stars". The Observatory. 36: 324–329. Bibcode:1913Obs....36..324R.
Jump up ^ Strömgren, Bengt (1933). "On the Interpretation of the Hertzsprung-Russell-Diagram". Zeitschrift für Astrophysik. 7: 222–248. Bibcode:1933ZA......7..222S.
Jump up ^ Schatzman, Evry L.; Praderie, Francoise (1993). The Stars. Springer. pp. 96–97. ISBN 3-540-54196-9.
Jump up ^ Morgan, W. W.; Keenan, P. C.; Kellman, E. (1943). An atlas of stellar spectra, with an outline of spectral classification. Chicago, Illinois: The University of Chicago press. Retrieved 2008-08-12.
^ Jump up to: a b c Unsöld, Albrecht (1969). The New Cosmos. Springer-Verlag New York Inc. p. 268. ISBN 0-387-90886-2.
Jump up ^ Gloeckler, George; Geiss, Johannes (2004). "Composition of the local interstellar medium as diagnosed with pickup ions". Advances in Space Research. 34 (1): 53–60. Bibcode:2004AdSpR..34...53G. doi:10.1016/j.asr.2003.02.054.
^ Jump up to: a b c Kroupa, Pavel (2002). "The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems". Science. 295 (5552): 82–91. arXiv:astro-ph/0201098  . Bibcode:2002Sci...295...82K. doi:10.1126/science.1067524. PMID 11778039. Retrieved 2007-12-03.
Jump up ^ Schilling, Govert (2001). "New Model Shows Sun Was a Hot Young Star". Science. 293 (5538): 2188–2189. doi:10.1126/science.293.5538.2188. PMID 11567116. Retrieved 2007-02-04.
Jump up ^ "Zero Age Main Sequence". The SAO Encyclopedia of Astronomy. Swinburne University. Retrieved 2007-12-09.
Jump up ^ Hansen, Carl J.; Kawaler, Steven D. (1999), Stellar Interiors: Physical Principles, Structure, and Evolution, Astronomy and Astrophysics Library, Springer Science & Business Media, p. 39, ISBN 038794138X
^ Jump up to: a b c d Clayton, Donald D. (1983). Principles of Stellar Evolution and Nucleosynthesis. University of Chicago Press. ISBN 0-226-10953-4.
Jump up ^ "Main Sequence Stars". Australia Telescope Outreach and Education. Retrieved 2007-12-04.
Jump up ^ Moore, Patrick (2006). The Amateur Astronomer. Springer. ISBN 1-85233-878-4.
Jump up ^ "White Dwarf". COSMOS—The SAO Encyclopedia of Astronomy. Swinburne University. Retrieved 2007-12-04.
Jump up ^ "Origin of the Hertzsprung-Russell Diagram". University of Nebraska. Retrieved 2007-12-06.
Jump up ^ "A course on stars' physical properties, formation and evolution" (PDF). University of St. Andrews. Retrieved 2010-05-18.
Jump up ^ Siess, Lionel (2000). "Computation of Isochrones". Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles. Retrieved 2007-12-06. —Compare, for example, the model isochrones generated for a ZAMS of 1.1 solar masses. This is listed in the table as 1.26 times the solar luminosity. At metallicity Z=0.01 the luminosity is 1.34 times solar luminosity. At metallicity Z=0.04 the luminosity is 0.89 times the solar luminosity.
Jump up ^ Zombeck, Martin V. (1990). Handbook of Space Astronomy and Astrophysics (2nd ed.). Cambridge University Press. ISBN 0-521-34787-4. Retrieved 2007-12-06.
Jump up ^ "SIMBAD Astronomical Database". Centre de Données astronomiques de Strasbourg. Retrieved 2008-11-21.
Jump up ^ Luck, R. Earle; Heiter, Ulrike (2005). "Stars within 15 Parsecs: Abundances for a Northern Sample". The Astronomical Journal. 129 (2): 1063–1083. Bibcode:2005AJ....129.1063L. doi:10.1086/427250.
Jump up ^ "LTT 2151 – High proper-motion Star". Centre de Données astronomiques de Strasbourg. Retrieved 2008-08-12.
Jump up ^ Staff (2008-01-01). "List of the Nearest Hundred Nearest Star Systems". Research Consortium on Nearby Stars. Archived from the original on 2012-05-13. Retrieved 2008-08-12.
^ Jump up to: a b c d Brainerd, Jerome James (2005-02-16). "Main-Sequence Stars". The Astrophysics Spectator. Retrieved 2007-12-04.
^ Jump up to: a b c Karttunen, Hannu (2003). Fundamental Astronomy. Springer. ISBN 3-540-00179-4.
Jump up ^ Bahcall, John N.; Pinsonneault, M. H.; Basu, Sarbani (2001-07-10). "Solar Models: Current Epoch and Time Dependences, Neutrinos, and Helioseismological Properties". The Astrophysical Journal. 555 (2): 990–1012. arXiv:astro-ph/0212331  . Bibcode:2003PhRvL..90m1301B. doi:10.1086/321493.
Jump up ^ Salaris, Maurizio; Cassisi, Santi (2005). Evolution of Stars and Stellar Populations. John Wiley and Sons. p. 128. ISBN 0-470-09220-3.
Jump up ^ Oey, M. S.; Clarke, C. J. (2005). "Statistical Confirmation of a Stellar Upper Mass Limit". The Astrophysical Journal. 620 (1): L43–L46. arXiv:astro-ph/0501135  . Bibcode:2005ApJ...620L..43O. doi:10.1086/428396.
Jump up ^ Ziebarth, Kenneth (1970). "On the Upper Mass Limit for Main-Sequence Stars". Astrophysical Journal. 162: 947–962. Bibcode:1970ApJ...162..947Z. doi:10.1086/150726.
Jump up ^ Burrows, A.; Hubbard, W. B.; Saumon, D.; Lunine, J. I. (March 1993). "An expanded set of brown dwarf and very low mass star models". Astrophysical Journal, Part 1. 406 (1): 158–171. Bibcode:1993ApJ...406..158B. doi:10.1086/172427.
Jump up ^ Aller, Lawrence H. (1991). Atoms, Stars, and Nebulae. Cambridge University Press. ISBN 0-521-31040-7.
Jump up ^ Bressan, A. G.; Chiosi, C.; Bertelli, G. (1981). "Mass loss and overshooting in massive stars". Astronomy and Astrophysics. 102 (1): 25–30. Bibcode:1981A&A...102...25B.
Jump up ^ Lochner, Jim; Gibb, Meredith; Newman, Phil (2006-09-06). "Stars". NASA. Retrieved 2007-12-05.
Jump up ^ Gough, D. O. (1981). "Solar interior structure and luminosity variations". Solar Physics. 74 (1): 21–34. Bibcode:1981SoPh...74...21G. doi:10.1007/BF00151270.
Jump up ^ Padmanabhan, Thanu (2001). Theoretical Astrophysics. Cambridge University Press. ISBN 0-521-56241-4.
Jump up ^ Wright, J. T. (2004). "Do We Know of Any Maunder Minimum Stars?". The Astronomical Journal. 128 (3): 1273–1278. arXiv:astro-ph/0406338  . Bibcode:2004AJ....128.1273W. doi:10.1086/423221. Retrieved 2007-12-06.
Jump up ^ Tayler, Roger John (1994). The Stars: Their Structure and Evolution. Cambridge University Press. ISBN 0-521-45885-4.
Jump up ^ Sweet, I. P. A.; Roy, A. E. (1953). "The structure of rotating stars". Monthly Notices of the Royal Astronomical Society. 113 (6): 701–715. Bibcode:1953MNRAS.113..701S. doi:10.1093/mnras/113.6.701.
Jump up ^ Burgasser, Adam J.; Kirkpatrick, J. Davy; Lepine, Sebastien (July 5–9, 2004). Spitzer Studies of Ultracool Subdwarfs: Metal-poor Late-type M, L and T Dwarfs. Proceedings of the 13th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun. Hamburg, Germany: Dordrecht, D. Reidel Publishing Co. p. 237. Retrieved 2007-12-06.
Jump up ^ Green, S. F.; Jones, Mark Henry; Burnell, S. Jocelyn (2004). An Introduction to the Sun and Stars. Cambridge University Press. ISBN 0-521-54622-2.
Jump up ^ Richmond, Michael W. (2004-11-10). "Stellar evolution on the main sequence". Rochester Institute of Technology. Retrieved 2007-12-03.
^ Jump up to: a b Prialnik, Dina (2000). An Introduction to the Theory of Stellar Structure and Evolution. Cambridge University Press. ISBN 0-521-65937-X.
Jump up ^ Schröder, K.-P.; Connon Smith, Robert (May 2008). "Distant future of the Sun and Earth revisited". Monthly Notices of the Royal Astronomical Society. 386 (1): 155–163. arXiv:0801.4031  . Bibcode:2008MNRAS.386..155S. doi:10.1111/j.1365-2966.2008.13022.x.
Jump up ^ Arnett, David (1996). Supernovae and Nucleosynthesis: An Investigation of the History of Matter, from the Big Bang to the Present. Princeton University Press. ISBN 0-691-01147-8. —Hydrogen fusion produces 8×1018 erg/g while helium fusion produces 8×1017 erg/g.
Jump up ^ For a detailed historical reconstruction of the theoretical derivation of this relationship by Eddington in 1924, see: Lecchini, Stefano (2007). How Dwarfs Became Giants. The Discovery of the Mass-Luminosity Relation. Bern Studies in the History and Philosophy of Science. ISBN 3-9522882-6-8.
^ Jump up to: a b Rolfs, Claus E.; Rodney, William S. (1988). Cauldrons in the Cosmos: Nuclear Astrophysics. University of Chicago Press. ISBN 0-226-72457-3.
Jump up ^ Sackmann, I.-Juliana; Boothroyd, Arnold I.; Kraemer, Kathleen E. (November 1993). "Our Sun. III. Present and Future". Astrophysical Journal. 418: 457–468. Bibcode:1993ApJ...418..457S. doi:10.1086/173407.
Jump up ^ Hansen, Carl J.; Kawaler, Steven D. (1994). Stellar Interiors: Physical Principles, Structure, and Evolution. Birkhäuser. p. 28. ISBN 0-387-94138-X.
Jump up ^ Laughlin, Gregory; Bodenheimer, Peter; Adams, Fred C. (1997). "The End of the Main Sequence". The Astrophysical Journal. 482 (1): 420–432. Bibcode:1997ApJ...482..420L. doi:10.1086/304125.
Jump up ^ Imamura, James N. (1995-02-07). "Mass-Luminosity Relationship". University of Oregon. Archived from the original on December 14, 2006. Retrieved 2007-01-08.
Jump up ^ Fynbo, Hans O. U.; et al. (2004). "Revised rates for the stellar triple-α process from measurement of 12C nuclear resonances". Nature. 433 (7022): 136–139. doi:10.1038/nature03219. PMID 15650733.
Jump up ^ Sitko, Michael L. (2000-03-24). "Stellar Structure and Evolution". University of Cincinnati. Archived from the original on March 26, 2005. Retrieved 2007-12-05.
Jump up ^ Staff (2006-10-12). "Post-Main Sequence Stars". Australia Telescope Outreach and Education. Retrieved 2008-01-08.
Jump up ^ Girardi, L.; Bressan, A.; Bertelli, G.; Chiosi, C. (2000). "Evolutionary tracks and isochrones for low- and intermediate-mass stars: From 0.15 to 7 Msun, and from Z=0.0004 to 0.03". Astronomy and Astrophysics Supplement. 141 (3): 371–383. arXiv:astro-ph/9910164  . Bibcode:2000A&AS..141..371G. doi:10.1051/aas:2000126.
Jump up ^ Poelarends, A. J. T.; Herwig, F.; Langer, N.; Heger, A. (March 2008). "The Supernova Channel of Super-AGB Stars". The Astrophysical Journal. 675 (1): 614–625. arXiv:0705.4643  . Bibcode:2008ApJ...675..614P. doi:10.1086/520872.
Jump up ^ Krauss, Lawrence M.; Chaboyer, Brian (2003). "Age Estimates of Globular Clusters in the Milky Way: Constraints on Cosmology". Science. 299 (5603): 65–69. Bibcode:2003Sci...299...65K. doi:10.1126/science.1075631. PMID 12511641.
Further reading[edit]
General[edit]
Kippenhahn, Rudolf, 100 Billion Suns, Basic Books, New York, 1983.
Technical[edit]
Arnett, David, Supernovae and Nucleosynthesis, Princeton University Press, Princeton, 1996.
Bahcall, John N., Neutrino Astrophysics, Cambridge University Press, Cambridge, 1989.
Bahcall, John N., Pinsonneault, M.H., and Basu, Sarbani, "Solar Models: Current Epoch and Time Dependences, Neutrinos, and Helioseismological Properties," The Astrophysical Journal, 555, 990, 2001.
Barnes, C. A., Clayton, D. D., and Schramm, D. N.(eds.), Essays in Nuclear Astrophysics, Cambridge University Press, Cambridge, 1982.
Bowers, Richard L., and Deeming, Terry, Astrophysics I: Stars, Jones and Bartlett, Publishers, Boston, 1984.
Bradley W. Carroll & Dale A. Ostlie (2007). An Introduction to Modern Astrophysics. Person Education Addison-Wesley San Francisco. ISBN 0-8053-0402-9.
Chabrier, Gilles, and Baraffe, Isabelle, "Theory of Low-Mass Stars and Substellar Objects," Annual Review of Astronomy and Astrophysics, 38, 337, 2000.
Chandrasekhar, S., An Introduction to the study of stellar Structure, Dover Publications, Inc., New York, 1967.
Clayton, Donald D., Principles of Stellar Evolution and Nucleosynthesis, University of Chicago Press, Chicago, 1983.
Cox, J. P., and Giuli, R. T., Principles of Stellar Structure, Gordon and Breach, New York, 1968.
Fowler, William ., Caughlan, Georgeanne R., and Zimmerman, Barbara A., "Thermonuclear Reaction Rates, I," Annual Review of Astronomy and Astrophysics, 5, 525, 1967.
Fowler, William A., Caughlan, Georgeanne R., and Zimmerman, Barbara A., "Thermonuclear Reaction Rates, II, " Annual Review of Astronomy and Astrophysics, 13, 69, 1975.
Hansen, Carl J., Kawaler, Steven D., and Trimble, Virginia Stellar Interiors: Physical Principles, Structure, and Evolution, Second Edition, Springer-Verlag, New York, 2004.
Harris, Michael J., Fowler, William A., Caughlan, Georgeanne R., and Zimmerman, Barbara A., "Thermonuclear Reaction Rates, III," Annual Review of Astronomy and Astrophysics, 21, 165, 1983.
Iben, Icko, Jr, "Stellar Evolution Within and Off the Main Sequence," Annual Review of Astronomy and Astrophysics, 5, 571, 1967.
Iglesias, Carlos A, and Rogers, Forrest J., "Updated Opal Opacities," The Astrophysical Journal, 464, 943, 1996.
Kippenhahn, Rudolf, and Weigert, Alfred, Stellar Structure and Evolution, Springer-Verlag, Berlin, 1990.
Liebert, James, and Probst, Ronald G., "Very Low Mass Stars", Annual Review of Astronomy and Astrophysics, 25, 437, 1987.
Padmanabhan, T., Theoretical Astrophysics, Cambridge University Press, Cambridge, 2002.
Prialnik, Dina, An Introduction to the Theory of Stellar Structure and Evolution, Cambridge University Press, Cambridge, 2000.
Novotny, Eva, Introduction to Stellar Atmospheres and Interior, Oxford University Press, New York, 1973.
Shore, Steven N., The Tapestry of Modern Astrophysics, John Wiley and Sons, Hoboken, 2003.
[show]
v
t
e
Star
Formation
Accretion
Molecular cloud
Bok globule
Young stellar object
Protostar
Pre-main-sequence star
Herbig Ae/Be
Orion
T Tauri
FU Orionis
Herbig–Haro object
Hayashi track
Henyey track
Evolution
Main sequence
Red giant branch
Horizontal branch
Red clump
Asymptotic giant branch
Protoplanetary nebula
Planetary nebula
PG1159 star
Dredge-up
Instability strip
Luminous blue variable
Blue straggler
Stellar population
Supernova
Supernova impostor
Hypernova
Hertzsprung–Russell diagram
Color–color diagram
Luminosity class
Subdwarf
Dwarf
Blue
Red
White
Yellow
Brown
Subgiant
Giant
Blue
Red
Yellow
Bright giant
Supergiant
Blue
Red
Yellow
Hypergiant
Yellow
Spectral
classification
O
B
A
F
G
K
M
WR
Be
OB
Subdwarf O
Subdwarf B
Late-type
Chemically peculiar
Am
Ap/Bp
Barium
Carbon
CH
CN
Extreme helium
Lambda Boötis
Lead
HgMn
S
Technetium
Shell
Remnants
White dwarf
Helium planet
Neutron star
Radio-quiet
Pulsar
Binary
X-ray
Magnetar
Stellar black hole
X-ray binary
Burster
Hypothetical stars
Black dwarf
Exotic
Quark
Strange
Preon
Planck
Electroweak star
Dark-matter star
Dark-energy star
Black star
Gravastar
Frozen star
Q star
Quasi-star
Thorne–Żytkow object
Iron star
Blitzar
Nucleosynthesis
Deuterium burning
Lithium burning
Proton–proton chain
CNO cycle
Helium flash
Triple-alpha process
Alpha process
Carbon burning
Neon burning
Oxygen burning
Silicon burning
S-process
R-process
Fusor
Nova
Symbiotic
Remnant
Luminous red nova
Structure
Core
Convection zone
Microturbulence
Oscillations
Radiation zone
Atmosphere
Photosphere
Starspot
Chromosphere
Corona
Stellar wind
Bubble
Bipolar outflow
Accretion disk
Asteroseismology
Helioseismology
Eddington luminosity
Kelvin–Helmholtz mechanism
Properties
Designation
Dynamics
Effective temperature
Kinematics
Magnetic field
Absolute magnitude
Mass
Metallicity
Rotation
UBV color
Variable star
Mira variable
Star systems
Binary
Contact
Common envelope
Eclipsing
Symbiotic
Multiple
Star cluster
Open cluster
Globular cluster
Super star cluster
Planetary system
Earth's Solar System
Earth-centric
observation of
Pole star
Circumpolar star
Constellation
Asterism
Magnitude
Apparent
Extinction
Photographic
Radial velocity
Proper motion
Parallax
Photometric-standard star
Lists
Star names
Arabic
Chinese
Extremes
Most massive
Highest temperature
Largest volume
Smallest volume
Brightest
Historical
Most luminous
Nearest
Nearest bright
Stars with exoplanets
Brown dwarfs
White dwarfs
Milky Way novae
Notable supernovae
Supernova candidates
Supernova remnants
Planetary nebulae
Timeline of stellar astronomy
Related articles
Substellar object
Brown dwarf
Sub-brown dwarf
Planet
Galactic year
Galaxy
Supercluster
Guest star
Gravity
Icarus (most distant individual star)
Intergalactic star
Infrared dark cloud
Starfield
Category:Stars · Star portal
Retrieved from "https://en.wikipedia.org/w/index.php?title=Main_sequence&oldid=840969214"
Categories:
Hertzsprung–Russell classifications
Main-sequence stars
Star types
Stellar evolution
Hidden categories:
CS1 maint: Explicit use of et al.
Featured articles
Navigation menu
Personal tools
Not logged in
Talk
Contributions
Create account
Log in
Namespaces
Article
Talk
Variants
Views
Read
Edit
View history
More
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Wikipedia store
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact page
Tools
What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Wikidata item
Cite this page
Print/export
Create a book
Download as PDF
Printable version
In other projects
Wikimedia Commons
Languages
Afrikaans
العربية
Asturianu
Беларуская
Български
Bosanski
Català
Čeština
Deutsch
Eesti
Ελληνικά
Español
Euskara
فارسی
Français
Gaeilge
Galego
한국어
हिन्दी
Hrvatski
Bahasa Indonesia
Italiano
עברית
ქართული
Қазақша
Latina
Latviešu
Lëtzebuergesch
Lietuvių
Bahasa Melayu
မြန်မာဘာသာ
Nederlands
नेपाली
日本語
Norsk
Norsk nynorsk
Occitan
Plattdüütsch
Polski
Português
Română
Русский
Simple English
Slovenčina
Slovenščina
Српски / srpski
Srpskohrvatski / српскохрватски
Suomi
Svenska
Татарча/tatarça
ไทย
Türkçe
Українська
Tiếng Việt
中文
46 more
Edit links
This page was last edited on 13 May 2018, at 06:45.
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.
Privacy policy
About Wikipedia
Disclaimers
Contact Wikipedia
Developers
Cookie statement
Mobile view
Enable previews

values: mw-page-base noprint

values: mw-head-base noprint

values: This is a featured article. Click here for more information.

values: firstHeading firstHeading en

values: siteSub noprint

values: jump-to-nav mw-jump

attrs: role class

values:
note
hatnote navigation-not-searchable

values:
/wiki/Hipparcos_Catalogue
mw-redirect
Hipparcos Catalogue

attrs: alt src title width height srcset data-file-width data-file-height

values: float:right;clear:right;width:22.0em;margin:0 0 1.0em 1.0em;background:#f9f9f9;border:1px solid #aaa;padding:0.2em;border-spacing:0.4em 0;text-align:center;line-height:1.4em;font-size:88%

values:
/wiki/Proton%E2%80%93proton_chain
mw-redirect
Proton–proton chain

values:
/wiki/Icarus_(star)
mw-redirect
Icarus (star)

values:
/wiki/Edward_C._Pickering
mw-redirect
Edward C. Pickering

values:
/wiki/Vogt-Russell_theorem
mw-redirect
Vogt-Russell theorem

values:
/wiki/Spectral_type
mw-redirect
Spectral type

values:
/wiki/Giant_molecular_cloud
mw-redirect
Giant molecular cloud

values: width: 400px; float: right; clear: right; line-height: 1; text-align: center; background-color: #ffffff; position: relative; max-width: 100%; overflow-x: auto;

values:
/wiki/Orders_of_approximation
mw-redirect
Orders of approximation

values:
/wiki/Orange_dwarf
mw-redirect
Orange dwarf

values:
/wiki/Yellow_dwarf
mw-redirect
Yellow dwarf

values: {\displaystyle L=4\pi \sigma R^{2}T_{eff}^{4}}

values: vertical-align: -1.338ex; width:15.488ex; height:3.676ex;

values:
/wiki/Orders_of_magnitude
mw-redirect
Orders of magnitude

values:
/wiki/Proton-proton_chain_reaction
mw-redirect
Proton-proton chain reaction

values:
/wiki/Proton-proton_chain
mw-redirect
Proton-proton chain

values: Edit section: Luminosity-color variation

values: vertical-align: -0.349ex; margin-bottom: -0.322ex; width:7.948ex; height:2.176ex;

values: vertical-align: -2.505ex; width:43.071ex; height:5.843ex;

values: vertical-align: -0.838ex; width:3.992ex; height:2.509ex;

values: vertical-align: -0.838ex; width:3.517ex; height:2.509ex;

values: vertical-align: -0.671ex; width:3.669ex; height:2.009ex;

values:
/wiki/Triple_alpha_process
mw-redirect
Triple alpha process

values:
/wiki/Type_Ib_supernova
mw-redirect
Type Ib supernova

values:
/wiki/Type_Ic_supernova
mw-redirect
Type Ic supernova

values: display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle

values: margin:0.5em 0 0.5em 1em;border:solid #aaa 1px

values:
reflist mw-references-wrap
list-style-type: decimal;

values:
nofollow
external text
//arxiv.org/abs/astro-ph/9701131

values:
nofollow
external text
//doi.org/10.1103%2FRevModPhys.69.337

values:
nofollow
external text
//doi.org/10.1126%2Fscience.1100370

values:
/wiki/PubMed_Identifier
mw-redirect
PubMed Identifier

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/15218132

values: Category:CS1 maint: Explicit use of et al.

values:
nofollow
http://www.eso.org/public/news/eso1230/
external text

values:
/wiki/A._B._Pippard
mw-redirect
A. B. Pippard

values:
nofollow
external text
//www.worldcat.org/oclc/33102501

values:
nofollow
external text
//doi.org/10.1016%2Fj.asr.2003.02.054

values:
nofollow
external text
//arxiv.org/abs/astro-ph/0201098

values:
nofollow
external text
//doi.org/10.1126%2Fscience.1067524

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/11778039

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/11567116

values:
nofollow
http://simbad.u-strasbg.fr/simbad/
external text

values:
nofollow
external text
//doi.org/10.1086%2F427250

values:
nofollow
external text
//arxiv.org/abs/astro-ph/0212331

values:
nofollow
external text
//doi.org/10.1086%2F321493

values:
nofollow
external text
//arxiv.org/abs/astro-ph/0501135

values:
nofollow
external text
//doi.org/10.1086%2F428396

values:
nofollow
external text
//doi.org/10.1086%2F150726

values:
nofollow
external text
//doi.org/10.1086%2F172427

values:
nofollow
external text
//doi.org/10.1007%2FBF00151270

values:
nofollow
external text
//arxiv.org/abs/astro-ph/0406338

values:
nofollow
external text
//doi.org/10.1086%2F423221

values: Monthly Notices of the Royal Astronomical Society

values:
nofollow
external text
//doi.org/10.1093%2Fmnras%2F113.6.701

values:
nofollow
external text
//arxiv.org/abs/0801.4031

values:
nofollow
external text
//doi.org/10.1086%2F173407

values:
nofollow
external text
//doi.org/10.1086%2F304125

values:
nofollow
external text
//doi.org/10.1038%2Fnature03219

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/15650733

values:
nofollow
external text
//arxiv.org/abs/astro-ph/9910164

values:
nofollow
external text
//doi.org/10.1051%2Faas%3A2000126

values:
nofollow
external text
//arxiv.org/abs/0705.4643

values:
nofollow
external text
//doi.org/10.1086%2F520872

values:
nofollow
external text
//doi.org/10.1126%2Fscience.1075631

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/12511641

values: -moz-column-width: 30em; -webkit-column-width: 30em; column-width: 30em; list-style-type: decimal;

values:
/wiki/Cambridge_University
mw-redirect
Cambridge University

values:
/wiki/Oxford_University
mw-redirect
Oxford University

values:
row
navbox-group
text-align: center;;width:1%

values:
/wiki/Red_giant_branch
mw-redirect
Red giant branch

values:
/wiki/Blue_supergiant
mw-redirect
Blue supergiant

values:
/wiki/Red_supergiant
mw-redirect
Red supergiant

values:
/wiki/Yellow_supergiant
mw-redirect
Yellow supergiant

values:
/wiki/Late-type_star
mw-redirect
Late-type star

values:
/wiki/Deuterium_burning
mw-redirect
Deuterium burning

values:
/wiki/Stellar_designation
mw-redirect
Stellar designation

values:
/wiki/Eclipsing_binary
mw-redirect
Eclipsing binary

values: nowraplinks hlist collapsible collapsed navbox-inner

values: Discussion about edits from this IP address [ctrl-alt-n]

values: A list of edits made from this IP address [ctrl-alt-y]

values: You are encouraged to create an account and log in; however, it is not mandatory

values: You're encouraged to log in; however, it's not mandatory. [ctrl-alt-o]

values:
/wiki/Main_sequence
View the content page [ctrl-alt-c]
c

values: Discussion about the content page [ctrl-alt-t]

values: p-namespaces navigation vectorTabs p-namespaces-label

values:
p-variants
navigation
vectorMenu emptyPortlet
p-variants-label

values: Past revisions of this page [ctrl-alt-h]

values: p-views navigation vectorTabs p-views-label

values:
p-cactions
navigation
vectorMenu emptyPortlet
p-cactions-label

values:
mw-wiki-logo
/wiki/Main_Page
Visit the main page

values:
/wiki/Main_Page
Visit the main page [ctrl-alt-z]
z

values: Featured content – the best of Wikipedia

values: Find background information on current events

values:
/wiki/Special:Random
Load a random article [ctrl-alt-x]
x

values: portal navigation p-navigation p-navigation-label

values: Guidance on how to use and edit Wikipedia

values:
https://af.wikipedia.org/wiki/Hoofreeks
Hoofreeks – Afrikaans
af
af
interlanguage-link-target

values:
interlanguage-link interwiki-af
display: none;

values: النسق الأساسي – Arabic

values:
interlanguage-link interwiki-ast
display: none;

values: Галоўная паслядоўнасць – Belarusian

values:
interlanguage-link interwiki-be
display: none;

values: Главна последователност – Bulgarian

values:
interlanguage-link interwiki-bg
display: none;

values:
interlanguage-link interwiki-bs
display: none;

values:
interlanguage-link interwiki-ca
display: none;

values:
interlanguage-link interwiki-cs
display: none;

values:
interlanguage-link interwiki-de
display: none;

values:
https://et.wikipedia.org/wiki/Peajada
Peajada – Estonian
et
et
interlanguage-link-target

values:
interlanguage-link interwiki-et
display: none;

values: Κύρια ακολουθία – Greek

values:
interlanguage-link interwiki-el
display: none;

values:
interlanguage-link interwiki-eu
display: none;

values: رشته اصلی – Persian

values:
interlanguage-link interwiki-fa
display: none;

values:
interlanguage-link interwiki-fr
display: none;

values:
interlanguage-link interwiki-ga
display: none;

values:
interlanguage-link interwiki-gl
display: none;

values: interlanguage-link interwiki-ko badge-Q17437796 badge-featuredarticle

values: मुख्य अनुक्रम – Hindi

values:
interlanguage-link interwiki-hr
display: none;

values:
interlanguage-link interwiki-it
display: none;

values: הסדרה הראשית – Hebrew

values:
interlanguage-link interwiki-he
display: none;

values: მთავარი მიმდევრობა – Georgian

values:
interlanguage-link interwiki-ka
display: none;

values: Негізгі тізбек жұлдызы – Kazakh

values:
interlanguage-link interwiki-kk
display: none;

values:
interlanguage-link interwiki-la
display: none;

values:
interlanguage-link interwiki-lv
display: none;

values:
https://lb.wikipedia.org/wiki/Haaptrei
Haaptrei – Luxembourgish
lb
lb
interlanguage-link-target

values:
interlanguage-link interwiki-lb
display: none;

values:
interlanguage-link interwiki-lt
display: none;

values: ပင်မ အစီအစဉ် အတွင်းရှိကြယ် – Burmese

values:
interlanguage-link interwiki-my
display: none;

values:
interlanguage-link interwiki-nl
display: none;

values: मुख्य अनुक्रम – Nepali

values:
interlanguage-link interwiki-ne
display: none;

values:
interlanguage-link interwiki-ja
display: none;

values:
interlanguage-link interwiki-no
display: none;

values:
interlanguage-link interwiki-nn
display: none;

values:
interlanguage-link interwiki-oc
display: none;

values:
interlanguage-link interwiki-nds
display: none;

values:
interlanguage-link interwiki-pl
display: none;

values:
interlanguage-link interwiki-ro
display: none;

values: Главная последовательность – Russian

values:
interlanguage-link interwiki-simple
display: none;

values:
interlanguage-link interwiki-sk
display: none;

values:
interlanguage-link interwiki-sl
display: none;

values: Главни низ – Serbian

values:
interlanguage-link interwiki-sr
display: none;

values:
interlanguage-link interwiki-sh
display: none;

values:
interlanguage-link interwiki-fi
display: none;

values:
interlanguage-link interwiki-sv
display: none;

values: Баш эзлеклелек – Tatar

values:
interlanguage-link interwiki-tt
display: none;

values: แถบลำดับหลัก – Thai

values:
interlanguage-link interwiki-th
display: none;

values:
https://tr.wikipedia.org/wiki/Anakol
Anakol – Turkish
tr
tr
interlanguage-link-target

values:
interlanguage-link interwiki-tr
display: none;

values: Головна послідовність – Ukrainian

values:
interlanguage-link interwiki-uk
display: none;

values:
interlanguage-link interwiki-vi
display: none;

values: All languages (initial selection from common choices by you and others)

values: mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-Main_sequence rootpage-Main_sequence skin-vector action-view


text:
8 Out of 10 Cats
From Wikipedia, the free encyclopedia
Jump to: navigation, search
8 Out of 10 Cats
Genre
Comedy panel game
Directed by
Chris Howe (series 1–3)
Barbara Wiltshire (series 3–7 and 9–)
Richard Valentine (series 6, 8–12 and 14–)
Presented by
Jimmy Carr
Starring
Sean Lock (2005–15)
Dave Spikey (2005–06)
Jason Manford (2007–10)
Jon Richardson (2011–15)
Rob Beckett (2016—)
Aisling Bea (2016—)
Narrated by
John Pohlhammer
Theme music composer
Mat Osman
Country of origin
United Kingdom
Original language(s)
English
No. of series
20
No. of episodes
202 (as of 27 June 2017) (list of episodes)
Production
Executive producer(s)
Richard Osman
Dominic English (series 1)
Ruth Phillips (series 3–)
Producer(s)
Darren Smith (series 1–3)
Ruth Phillips (series 1–2)
Derek McLean (series 4–7)
Ruth Wallace (series 4–5)
Karen Murdoch (series 6–8)
Stu Mather (series 8–10)
Fiona McDermott (series 9)
Richard Cohen (series 11–)
Andrew Westwell (series 11–12)
Adam Hutchinson (series 13–)
Location(s)
BBC Television Centre (series 1–15)
Teddington Studios (series 16–17)
Pinewood Studios (series 16–)
Shepperton Studios (series 18)
MediaCityUK (Countdown editions)
Editor(s)
Tim Ellison (series 1–10 and 13–)
Ian Birchall (series 1–4 and 9–11)
Steve Andrews (series 1–3, 5, 7, 9–11 and 13–)
Bex Murray (series 1, 4–11 and 13–)
Damon Tai (series 2–11 & 14–)
Tom Jarvis (series 7)
Matthew Jeffreys (series 7)
Ben Heather (series 12–)
David Frisby (series 12)
Nick King (series 12)
Jamie Shemeld (series 15–)
Camera setup
Multi-camera
Running time
30 minutes (inc. adverts)
Production company(s)
Zeppotron
Distributor
Endemol UK
Release
Original network
Channel 4 (2005–2015)
More4 (2016–2017)
E4 (2017–)
Picture format
HDTV 1080i
Audio format
Stereophonic
Original release
3 June 2005 (2005-06-03) – present
Chronology
Related shows
8 Out of 10 Cats: Uncut
8 Out of 10 Cats Does Countdown
External links
Official website
www.channel4.com/programmes/8-out-of-10-cats
8 Out of 10 Cats is a British television comedy panel game produced by Zeppotron (a subsidiary of Endemol UK) for E4. It was first broadcast on 3 June 2005. The show is hosted by Jimmy Carr and the current team captains are Rob Beckett and Aisling Bea.
The show is based on statistics and opinion polls, and draws on polls produced by a variety of organisations and new polls commissioned for the programme, carried out by Harris Poll. The title is derived from a well-known advertising tagline for Whiskas cat food, which claimed that "8 out of 10 cats prefer Whiskas".[1]
Contents
[hide]
1 Overview
2 Current rounds
3 Former rounds
4 8 Out of 10 Cats Does Countdown
5 Other specials
6 Podcasts
7 Cast
8 Episodes
8.1 Original series
8.2 Specials
9 DVD
10 References
11 External links
Overview[edit]
The show is hosted by comedian Jimmy Carr and features two teams, consisting of a regular team captain and two celebrity guests each. Sean Lock appeared as the first team captain from series 1 to 18; he was replaced by Rob Beckett at the beginning of series 19.[2] The opposing captain was originally Dave Spikey, who left after series 4 and was replaced by Jason Manford.[3] Manford departed following series 10, and was replaced by Jon Richardson for series 11 to 18.[4] From series 19, the opposing captain is Aisling Bea.[2]
Every week, the captains are joined by two celebrities. Often, topical celebrities appear on the show, for example Ruth Badger following her appearance on The Apprentice.
The show is currently recorded at Pinewood Studios, previously at BBC Television Centre, typically the day before transmission. However, in the past few years, due to Jimmy Carr's stand-up schedule, certain episodes are pretaped and broadcast later as "special" episodes dealing with a particular subject.[5]
2015 was the only year since the show began in 2005 in which a full series was not broadcast. Two Christmas Specials however were filmed for airing on 24 and 30 December 2015. 8 Out of 10 Cats Does Countdown however aired for a total of 24 episodes throughout 2015.
Current rounds[edit]
The current rounds featured on 8 Out of 10 Cats are:[6]
"What Are You Talking About?" – The polling organisation asked the public what they were talking about during the week. The teams have to try to guess the top three.
"Pick of the Polls" – The teams are given four pictures to pick from and are given a poll based on that picture.
"Believe It or Not" – The teams are given a statistic and try to guess if it is true or false.
"And the Winner Is..." – The teams are given a question from a poll and then they try to guess what came on top of that poll.
"The Poll with a Hole" – each team is given a statistic but it is missing one piece of salient information. The teams have to guess what that piece of information is.
Until series 8 there were four rounds during the game, but it has since been reduced to three. The points often do not add up correctly, as the show has to be edited to fit in its 26-minute slot. From series 9 there is a longer version of the show called 8 Out of 10 Cats Uncut, broadcast a few days later.
Former rounds[edit]
These rounds only featured in series 1 and the Big Brother special shows:[6]
"Face Off" – The teams have to guess who from a list of famous people came top with respect to a particular topic.
"Word Association" – The teams view a clip illustrating a word and have to guess the top three things people thought of when they heard that word.
"What's the Poll?" – The teams are given five famous people, picture by picture, and they have to guess which poll they appeared on.
8 Out of 10 Cats Does Countdown[edit]
Main article: 8 Out of 10 Cats Does Countdown
Since 2012, crossover episodes between 8 Out of 10 Cats and Countdown have aired. The show follows the format of Countdown, but is hosted by Jimmy Carr, with permanent contestants Sean Lock and Jon Richardson, as well as two other guest contestants.
Other specials[edit]
On 4 January 2013, a special episode of Deal or No Deal featuring Carr as host alongside Richardson and Lock aired during another Channel 4 "mash-up night", the story behind it being that Noel Edmonds had been driven to leave when Derren Brown was playing, and was getting all the boxes from lowest to highest. Noel ran away with the £250,000 box, saying that he "spent it all on his shirt". The backstage personnel then took out a hammer and smashed the 'break glass for Jimmy Carr' box, which produced a horn, which was used to call Carr to the set.
Joe Wilkinson guest starred as the Banker's assistant. Guests were Nicola Adams, Rob Beckett, Gemma Collins, Mia Cross, Corinne Davies, Susie Dent, Matt Forde, John Fothergill, Stephen Frost, Nick Helm, Elis James, Dave Johns, Tony Law, Alice Levine, Mark Olver, Rachel Riley, John Robins, Katherine Ryan, Nong Skett, Andy Smart and Holly Walsh.
Podcasts[edit]
A series of podcasts have also been released on iTunes, with material directly from the show for several episodes. Each podcast is typically the "What Are You Talking About" round from that episode.
Cast[edit]
Role
Series
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Presenter Jimmy Carr
Team captains Sean Lock Rob Beckett
Dave Spikey Jason Manford Jon Richardson Aisling Bea
Episodes[edit]
Main article: List of 8 Out of 10 Cats episodes
Original series[edit]
The coloured backgrounds denote the result of each of the series:
– Indicates Sean's/Rob's team won.
– Indicates Dave's/Jason's/Jon's/Aisling's team won.
– Indicates the series ended in a draw.
Series
Start date
End date
Episodes
1 3 June 2005 5 August 2005 10
2 10 February 2006 24 March 2006 7
3 26 May 2006 14 July 2006 9
4 20 October 2006 8 December 2006 8
5 15 June 2007 20 July 2007 6
6 13 June 2008 18 July 2008 6
7 4 September 2008 27 November 2008 14
8 5 June 2009 17 July 2009 7
9 8 January 2010 19 February 2010 7
10 17 September 2010 15 October 2010 5
11 17 June 2011 19 August 2011 10
12 23 September 2011 25 November 2011 10
13 27 April 2012 22 June 2012 9
14 8 October 2012 10 December 2012 9
15 18 January 2013 29 March 2013 10
16 4 October 2013 29 November 2013 9
17 17 February 2014 14 April 2014 9
18 6 October 2014 1 December 2014 9
19 8 November 2016 18 January 2017 8
20 16 May 2017 18 July 2017 10
Specials[edit]
See also: 8 Out of 10 Cats Does Countdown § Episodes
Date
Entitle
Special Guests
12 August 2005 Big Brother 6 Special –
18 August 2006 Big Brother 7 Special –
15 December 2006 The Best of Series 4 –
30 August 2007 Big Brother 8 Special –
5 September 2008 Big Brother 9 Special –
26 December 2008 The Best of Series 7 –
24 July 2009 The Best of Series 8 –
11 June 2010 Footy World Cup Special –
21 August 2010 The Best of Series 9 –
9 September 2010 Big Brother 1–11 Special –
23 December 2010 Christmas Special –
5 March 2011 24 Hour Panel People Comic Relief Special –
26 August 2011 The Best of Series 11 –
9 December 2011 The Best of Series 12 –
23 December 2011 Christmas Special –
29 June 2012 The Best of Series 13 (Part 1) –
6 July 2012 The Best of Series 13 (Part 2) –
17 December 2012 The Best of Series 14 (Part 1) –
17 December 2012 The Best of Series 14 (Part 2) –
24 December 2012 Christmas Special –
4 January 2013 8 Out of 10 Cats does Deal or No Deal Sean Lock, Jon Richardson
5 July 2013 The Best of Series 15 (Part 1) –
9 September 2013 The Best of Series 15 (Part 2) –
6 December 2013 The Best of Series 16 –
29 December 2013 Christmas Special Holly Willoughby, Alan Davies, Henning Wehn, Roisin Conaty, Nick Helm, Joe Wilkinson
13 August 2014 The Best of Series 17 (Part 1) –
20 August 2014 The Best of Series 17 (Part 2) –
8 December 2014 Jimmy, Sean & Jon's Best Bits –
15 December 2014 The Best of Series 18 –
23 December 2014 Christmas Special Roisin Conaty, Freddie Flintoff, Jonathan Ross and Ricky Wilson
24 December 2015 Christmas Special Peter Andre, Seann Walsh, Roisin Conaty and Joe Lycett
29 December 2015 End of Year Special Joey Essex, Romesh Ranganathan, Isy Suttie and Richard Osman
21 December 2016 Christmas Special –
4 January 2017 New Year Special –
25 January 2017 The Best of Series 19 (Part 1) –
1 February 2017 The Best of Series 19 (Part 2) –
25 July 2017 The Best of Series 20 –
DVD[edit]
8 Out of 10 Cats: Claws Out is a ninety-minute collection of highlights from the first few series which features deleted scenes considered too offensive to be aired. It was released on 20 November 2006.[7]
References[edit]
Jump up ^ "Trivia for 8 Out of 10 Cats". Internet Movie Database. Retrieved 12 December 2010.
^ Jump up to: a b Metro.co.uk, Katie Baillie for (12 October 2016). "8 Out Of 10 Cats is coming backand there are two new team captains".
Jump up ^ "8 Out of 10 Cats – Production Details". British Comedy Guide. Retrieved 12 December 2010.
Jump up ^ "sro audiences". www.sroaudiences.com.
Jump up ^ "Free audience tickets for 8 OUT OF 10 CATS taping at ELSTREE STUDIOS from SRO Audiences". www.sroaudiences.com.
^ Jump up to: a b "About 8 Out of 10 Cats". British Comedy Guide. Retrieved 12 December 2010.
Jump up ^ "DVD details for 8 Out of 10 Cats". Internet Movie Database. Retrieved 12 December 2010.
External links[edit]
8 Out of 10 Cats at channel4.com
8 Out of 10 Cats at TV.com
8 Out of 10 Cats on IMDb
8 Out of 10 Cats at British Comedy Guide
8 Out of 10 Cats at EpisodeWorld.com
Retrieved from "https://en.wikipedia.org/w/index.php?title=8_Out_of_10_Cats&oldid=807934155"
Categories:
2005 British television programme debuts
2000s British comedy television series
2010s British comedy television series
Channel 4 comedy
Channel 4 panel games
English-language television programs
Television series by Zeppotron
Hidden categories:
Use dmy dates from February 2014
Use British English from February 2014
Pages using infobox television with editor parameter
Navigation menu
Personal tools
Not logged in
Talk
Contributions
Create account
Log in
Namespaces
Article
Talk
Variants
Views
Read
Edit
View history
More
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Wikipedia store
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact page
Tools
What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Wikidata item
Cite this page
Print/export
Create a book
Download as PDF
Printable version
Languages
Cymraeg
Français
Nederlands
Simple English
Edit links
This page was last edited on 30 October 2017, at 22:36.
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.
Privacy policy
About Wikipedia
Disclaimers
Contact Wikipedia
Developers
Cookie statement
Mobile view
Enable previews

key: html

type: local

value: div

attrs: id class

values: mw-page-base noprint

values: mw-head-base noprint

value: a

value: i

attrs: id class lang

values: firstHeading firstHeading en

values: siteSub noprint

values: jump-to-nav mw-jump

value: th

attrs: colspan class style

values: text-align:center;font-size:125%;font-weight:bold;font-style: italic; background: #CCCCFF; padding: 0.25em 1em; line-height: 1.5em;

value: tr

value: img

attrs: alt src width height srcset data-file-width data-file-height

attrs: href class

value: td

attrs: colspan style

attrs: href title

attrs: href class title

values:
/wiki/Panel_game
mw-redirect
Panel game

value: small

values: text-align:center;background: #CCCCFF; padding: 0.25em 1em; line-height: 1.5em;

values:
/wiki/BBC_Television_Centre
mw-redirect
BBC Television Centre

values:
/wiki/British_television
mw-redirect
British television

values:
/wiki/Harris_Interactive
mw-redirect
Harris Interactive

values:
/wiki/The_Apprentice_(UK)
mw-redirect
The Apprentice (UK)

values:
/wiki/Big_Brother_(UK)
mw-redirect
Big Brother (UK)

values: Edit section: 8 Out of 10 Cats Does Countdown

values: background-color:#ffdddd; color:; border:1px solid darkgray; text-align:center;

values: background-color:#ccffcc; color:; border:1px solid darkgray; text-align:center;

values: background-color:#ffffdd; color:; border:1px solid darkgray; text-align:center;

values:
/wiki/Freddie_Flintoff
mw-redirect
Freddie Flintoff

values:
/wiki/Ricky_Wilson_(British_musician)
mw-redirect
Ricky Wilson (British musician)

values:
/wiki/Internet_Movie_Database
mw-redirect
Internet Movie Database

values:
nofollow
external text
http://www.sroaudiences.com/shows.asp

values:
nofollow
external text
http://www.imdb.com/title/tt0465315/dvd

values: -moz-column-width: 30em; -webkit-column-width: 30em; column-width: 30em; list-style-type: decimal;

values:
nofollow
http://www.imdb.com/title/tt0465315/
external text

values: Category:2005 British television programme debuts

values: Category:2000s British comedy television series

values: Category:2010s British comedy television series

values: Category:Use dmy dates from February 2014

values: Category:Use British English from February 2014

values: Category:Pages using infobox television with editor parameter

values: Discussion about edits from this IP address [ctrl-alt-n]

values: A list of edits made from this IP address [ctrl-alt-y]

values: You are encouraged to create an account and log in; however, it is not mandatory

values: You're encouraged to log in; however, it's not mandatory. [ctrl-alt-o]

values:
/wiki/8_Out_of_10_Cats
View the content page [ctrl-alt-c]
c

values: Discussion about the content page [ctrl-alt-t]

values: p-namespaces navigation vectorTabs p-namespaces-label

values:
p-variants
navigation
vectorMenu emptyPortlet
p-variants-label

values: Past revisions of this page [ctrl-alt-h]

values: p-views navigation vectorTabs p-views-label

values:
p-cactions
navigation
vectorMenu emptyPortlet
p-cactions-label

values:
mw-wiki-logo
/wiki/Main_Page
Visit the main page

values:
/wiki/Main_Page
Visit the main page [ctrl-alt-z]
z

values: Featured content – the best of Wikipedia

values: Find background information on current events

values:
/wiki/Special:Random
Load a random article [ctrl-alt-x]
x

values: portal navigation p-navigation p-navigation-label

values: Guidance on how to use and edit Wikipedia

values: About the project, what you can do, where to find things

values: A list of recent changes in the wiki [ctrl-alt-r]

values: portal navigation p-interaction p-interaction-label

values: List of all English Wikipedia pages containing links to this page [ctrl-alt-j]

values: Recent changes in pages linked from this page [ctrl-alt-k]

values:
/wiki/Wikipedia:File_Upload_Wizard
Upload files [ctrl-alt-u]
u

values: A list of all special pages [ctrl-alt-q]

values: Permanent link to this revision of the page

values: Link to connected data repository item [ctrl-alt-g]

values: Printable version of this page [ctrl-alt-p]

values:
uls-settings-trigger
Language settings
0
button
true

values: /static/images/wikimedia-button-1.5x.png 1.5x, /static/images/wikimedia-button-2x.png 2x

values: /static/images/poweredby_mediawiki_132x47.png 1.5x, /static/images/poweredby_mediawiki_176x62.png 2x

values:
suggestions
display: none; font-size: 13px;

values: mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-8_Out_of_10_Cats rootpage-8_Out_of_10_Cats vector-experimental-print-styles vector-nav-directionality skin-vector action-view