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Red giant

Index Red giant

A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses) in a late phase of stellar evolution. [1]

59 relations: Aldebaran, Alpha Herculis, Arcturus, Astronomical unit, Asymptotic giant branch, Atomic number, Carbon star, Chi Cygni, Circumstellar habitable zone, Convection zone, Corona, Degenerate matter, Delta Andromedae, Dredge-up, Effective temperature, Gamma Cephei, Gamma Crucis, Giant star, Granule (solar physics), Hamal, HD 208527, HD 220074, Helium flash, Hertzsprung–Russell diagram, Horizontal branch, Hydrostatic equilibrium, Interstellar medium, Iota Draconis, Jupiter, Kappa Persei, Main sequence, Mars, Metallicity, Mira, Molecular cloud, Photosphere, Planetary nebula, Planetary system, Pollux (star), Red clump, Red giant (disambiguation), Red supergiant star, Red-giant branch, Roche lobe, S-type star, Saturn, Solar mass, Star formation, Stellar classification, Stellar evolution, ..., Stellar nucleosynthesis, Sun, Supergiant star, Supernova, Thermonuclear fusion, Triple-alpha process, Variable star, White dwarf, Wolf–Rayet star. Expand index (9 more) »


Aldebaran, designated Alpha Tauri (α Tauri, abbreviated Alpha Tau, α Tau), is an orange giant star located about 65 light-years from the Sun in the zodiac constellation of Taurus.

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Alpha Herculis

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Astronomical unit

The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.

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Asymptotic giant branch

The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars.

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Atomic number

The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.

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Carbon star

A carbon star is typically an asymptotic giant branch star, a luminous red giant, whose atmosphere contains more carbon than oxygen; the two elements combine in the upper layers of the star, forming carbon monoxide, which consumes all the oxygen in the atmosphere, leaving carbon atoms free to form other carbon compounds, giving the star a "sooty" atmosphere and a strikingly ruby red appearance.

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Chi Cygni

Chi Cygni (χ Cyg, χ Cygni) is a variable star of the Mira type in the constellation Cygnus, and also an S-type star.

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Circumstellar habitable zone

In astronomy and astrobiology, the circumstellar habitable zone (CHZ), or simply the habitable zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.

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Convection zone

A convection zone, convective zone or convective region of a star is a layer which is unstable to convection.

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A corona (Latin, 'crown') is an aura of plasma that surrounds the Sun and other stars.

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Degenerate matter

Degenerate matter is a highly dense state of matter in which particles must occupy high states of kinetic energy in order to satisfy the Pauli exclusion principle.

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Delta Andromedae

Delta Andromedae (δ And, δ Andromedae) is a multiple star system in the northern constellation of Andromeda.

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A dredge-up is a period in the evolution of a star where a surface convection zone extends down to the layers where material has undergone nuclear fusion.

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Effective temperature

The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation.

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Gamma Cephei

Gamma Cephei (γ Cephei, abbreviated Gamma Cep, γ Cep) is a binary star system approximately 45 light-years away in the constellation of Cepheus.

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Gamma Crucis

Gamma Crucis (γ Crucis, abbreviated Gamma Cru, γ Cru), also named Gacrux, is the nearest M-Giant star to the Sun.

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Giant star

A giant star is a star with substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature.

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Granule (solar physics)

Granules on the photosphere of the Sun are caused by convection currents (thermal columns, Bénard cells) of plasma within the Sun's convective zone.

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Hamal, alternatively designated Alpha Arietis (α Arietis, abbreviated Alpha Ari, α Ari), is the brightest star in the northern zodiacal constellation of Aries.

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HD 208527

HD 208527 is a M1III red giant star located in Pegasus.

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HD 220074

HD 220074 is a M2III red giant star located in Cassiopeia.

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Helium flash

A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low mass stars (between 0.8 solar masses and 2.0) during their red giant phase (the Sun is predicted to experience a flash 1.2 billion years after it leaves the main sequence).

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Hertzsprung–Russell diagram

The Hertzsprung–Russell diagram, abbreviated H–R diagram, HR diagram or HRD, is a scatter plot of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their stellar classifications or effective temperatures.

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Horizontal branch

The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red giant branch in stars whose masses are similar to the Sun's.

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Hydrostatic equilibrium

In fluid mechanics, a fluid is said to be in hydrostatic equilibrium or hydrostatic balance when it is at rest, or when the flow velocity at each point is constant over time.

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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.

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Iota Draconis

Iota Draconis (ι Draconis, abbreviated Iota Dra, ι Dra), also named Edasich, is a star in the northern circumpolar constellation of Draco.

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Jupiter is the fifth planet from the Sun and the largest in the Solar System.

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Kappa Persei

Kappa Persei (κ Persei, abbreviated Kap Per, κ Per) is a triple star system in the northern constellation of Perseus.

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Main sequence

In astronomy, the main sequence is a continuous and distinctive band of stars that appear on plots of stellar color versus brightness.

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Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.

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In astronomy, metallicity is used to describe the abundance of elements present in an object that are heavier than hydrogen or helium.

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Mira, alternatively designated Omicron Ceti (ο Ceti, abbreviated Omicron Cet, ο Cet) is a red giant star estimated to be 200–400 light years from the Sun in the constellation of Cetus.

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Molecular cloud

A molecular cloud, sometimes called a stellar nursery (if star formation is occurring within), is a type of interstellar cloud, the density and size of which permit the formation of molecules, most commonly molecular hydrogen (H2).

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The photosphere is a star's outer shell from which light is radiated.

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Planetary nebula

A planetary nebula, abbreviated as PN or plural PNe, is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives.

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Planetary system

A planetary system is a set of gravitationally bound non-stellar objects in or out of orbit around a star or star system.

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Pollux (star)

Pollux, also designated Beta Geminorum (β Geminorum, abbreviated Beta Gem, β Gem), is an orange-hued evolved giant star approximately 34 light-years from the Sun in the northern constellation of Gemini.

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Red clump

The red clump is a clustering of red giants in the Hertzsprung–Russell diagram at around 5,000 K and absolute magnitude (MV) +0.5, slightly hotter than most red-giant-branch stars of the same luminosity.

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Red giant (disambiguation)

Red giant and similar can mean.

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Red supergiant star

Red supergiants are stars with a supergiant luminosity class (Yerkes class I) of spectral type K or M. They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous.

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Red-giant branch

The red-giant branch (RGB), sometimes called the first giant branch, is the portion of the giant branch before helium ignition occurs in the course of stellar evolution.

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Roche lobe

The Roche lobe (or Roche limit) is the region around a star in a binary system within which orbiting material is gravitationally bound to that star.

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S-type star

An S-type star (or just S star) is a cool giant with approximately equal quantities of carbon and oxygen in its atmosphere.

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Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.

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Solar mass

The solar mass is a standard unit of mass in astronomy, equal to approximately.

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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.

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Stellar classification

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

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Stellar evolution

Stellar evolution is the process by which a star changes over the course of time.

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Stellar nucleosynthesis

Stellar nucleosynthesis is the theory explaining the creation (nucleosynthesis) of chemical elements by nuclear fusion reactions between atoms within the stars.

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The Sun is the star at the center of the Solar System.

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Supergiant star

Supergiants are among the most massive and most luminous stars.

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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.

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Thermonuclear fusion

Thermonuclear fusion is a way to achieve nuclear fusion by using extremely high temperatures.

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Triple-alpha process

The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon.

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Variable star

A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.

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White dwarf

A white dwarf, also called a degenerate dwarf, is a stellar core remnant composed mostly of electron-degenerate matter.

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Wolf–Rayet star

Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectra showing prominent broad emission lines of highly ionised helium and nitrogen or carbon.

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Redirects here:

M giant, M-type giant, Red Giant, Red giant branch star, Red giant star, Red giants, Red-giant, Red-giant branch star, Red-giant branch stars, Red-giant-branch star, Red-giant-branch stars, The red giant.


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

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