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Turnoff Point
The turnoff point for a star refers to the point on the Hertzsprung-Russell diagram where it leaves the main sequence after the exhaustion of its main fuel. It is often referred to as the main sequence turnoff. By plotting the turnoff point of the stars in star clusters, one can estimate the cluster's age. Stars with no turnoff point Red dwarfs are stars of 0.08–0.4 solar masses and are also referred to as class M stars. Red dwarfs have sufficient hydrogen mass to sustain hydrogen Nuclear fusion, fusion to helium via the proton-proton chain reaction, but do not have sufficient mass to create the temperatures and pressures necessary to fuse helium to carbon, nitrogen or oxygen (see CNO cycle). However, all their hydrogen is available for fusion, and the low temperatures and pressures mean the lifetimes of these stars on the main sequence from zero point to turn off point is measured in trillions of years. For example, the lifespan of a star of 0.1 solar masses is 6 trillion ye ...
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Open Cluster HR Diagram Ages
Open or OPEN may refer to: Music * Open (band), Australian pop/rock band * The Open (band), English indie rock band * Open (Blues Image album), ''Open'' (Blues Image album), 1969 * Open (Gotthard album), ''Open'' (Gotthard album), 1999 * Open (Cowboy Junkies album), ''Open'' (Cowboy Junkies album), 2001 * Open (YFriday album), ''Open'' (YFriday album), 2001 * Open (Shaznay Lewis album), ''Open'' (Shaznay Lewis album), 2004 * Open (Jon Anderson EP), ''Open'' (Jon Anderson EP), 2011 * Open (Stick Men album), ''Open'' (Stick Men album), 2012 * Open (The Necks album), ''Open'' (The Necks album), 2013 * ''Open'', a 1967 album by Julie Driscoll, Brian Auger and the Trinity * ''Open'', a 1979 album by Steve Hillage * Open (Queensrÿche song), "Open" (Queensrÿche song) * Open (Mýa song), "Open" (Mýa song) * "Open", the first song on The Cure album ''Wish (The Cure album), Wish'' Literature * Open (Mexican magazine), ''Open'' (Mexican magazine), a lifestyle Mexican publication * Open ...
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Nitrogen
Nitrogen is the chemical element upright=1.0, 500px, The chemical elements ordered by link=Periodic table In chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, eleme ... with the symbol A symbol is a mark, sign, or that indicates, signifies, or is understood as representing an , , or . Symbols allow people to go beyond what is n or seen by creating linkages between otherwise very different s and s. All (and ) is achieved th ... N and atomic number 300px, The Rutherford–Bohr model of the hydrogen atom () or a hydrogen-like ion (). In this model it is an essential feature that the photon energy (or frequency) of the electromagnetic radiation emitted (shown) when an electron jumps from one ... 7. It was first discovered and isolated by Scottish physician Daniel Rutherford Daniel Rutherford (3 November 1749 – 15 December 1819) was a Scottish physic ...
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Electron Degeneracy Pressure
Electron degeneracy pressure is a particular manifestation of the more general phenomenon of quantum degeneracy pressure. The Pauli exclusion principle The Pauli exclusion principle is the quantum mechanical principle which states that two or more identical fermion In particle physics Particle physics (also known as high energy physics) is a branch of physics Physics (from grc ... disallows two identical half-integer spin Spin or spinning may refer to: Businesses * or South Pacific Island Network * , an American scooter-sharing system * , a chain of table tennis lounges Computing * , 's tool for formal verification of distributed software systems * , a Mach-like ... particles (electron The electron is a subatomic particle (denoted by the symbol or ) whose electric charge is negative one elementary charge. Electrons belong to the first generation (particle physics), generation of the lepton particle family, and are general ...s and all other fermi ...
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Gravity
Gravity (), or gravitation, is a natural phenomenon Types of natural phenomena include: Weather, fog, thunder, tornadoes; biological processes, decomposition, germination seedlings, three days after germination. Germination is the process by which an organism grows from a seed or similar s ... by which all things with mass Mass is the quantity Quantity is a property that can exist as a multitude or magnitude, which illustrate discontinuity and continuity. Quantities can be compared in terms of "more", "less", or "equal", or by assigning a numerical value ... or energy In physics Physics is the that studies , its , its and behavior through , and the related entities of and . "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regula ...—including planet A planet is an astronomical body orbiting a star or Stellar evolution#Stellar remnants, stellar remnant that is ...
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Radiation
In physics Physics is the natural science that studies matter, its Elementary particle, fundamental constituents, its Motion (physics), motion and behavior through Spacetime, space and time, and the related entities of energy and force. "Physical scie ..., radiation is the emission or transmission of energy In physics Physics is the that studies , its , its and behavior through , and the related entities of and . "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regula ... in the form of wave In physics Physics is the that studies , its , its and behavior through , and the related entities of and . "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular su ...s or particle In the Outline of physical science, physical sciences, a particle (or corpuscule in older texts) is a small wikt:local, localiz ...
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Stellar Nucleosynthesis
Stellar nucleosynthesis is the creation (nucleosynthesis) of chemical element In chemistry, an element is a pure Chemical substance, substance consisting only of atoms that all have the same numbers of protons in their atomic nucleus, nuclei. Unlike chemical compounds, chemical elements cannot be broken down into simp ...s by nuclear fusion 400 px, The nuclear binding energy curve. The formation of nuclei with masses up to iron-56 releases energy, as illustrated above. Nuclear fusion is a nuclear reaction, reaction in which two or more atomic nuclei are combined to form one or m ... reactions within stars. Stellar nucleosynthesis has occurred since the original creation of hydrogen Hydrogen is the chemical element with the Symbol (chemistry), symbol H and atomic number 1. Hydrogen is the lightest element. At standard temperature and pressure, standard conditions hydrogen is a gas of diatomic molecules having the che ..., helium Helium (from el, ἥλ ...
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Universe
The universe ( la, universus) is all of space Space is the boundless three-dimensional Three-dimensional space (also: 3-space or, rarely, tri-dimensional space) is a geometric setting in which three values (called parameter A parameter (from the Ancient Greek language, Ancient Gre ... and time Time is the continued sequence of existence and event (philosophy), events that occurs in an apparently irreversible process, irreversible succession from the past, through the present, into the future. It is a component quantity of various me ... and their contents, including planet A planet is an astronomical body orbiting a star or Stellar evolution#Stellar remnants, stellar remnant that is massive enough to be Hydrostatic equilibrium, rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and ...s, star A star is an astronomical object consisting of a luminous spheroid of plasma Plasma or plasm may refer to: Science * Plasma ...
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Wiley-VCH
Wiley-VCH is a German German(s) may refer to: Common uses * of or related to Germany * Germans, Germanic ethnic group, citizens of Germany or people of German ancestry * For citizens of Germany, see also German nationality law * German language The German la ... publisher Publishing is the activity of making information, literature, music, software and other content available to the public for sale or for free. Traditionally, the term refers to the creation and distribution of printed works, such as book A ... owned by John Wiley & Sons John Wiley & Sons, Inc., commonly known as Wiley (), is an American Multinational corporation, multinational publishing company founded in 1807 that focuses on academic publishing and instructional materials. The company produces books, Academic .... It was founded in 1921 as Verlag Chemie (meaning "Chemistry Press": VCH stands for ''Verlag Chemie'') by two German learned societies A learned society (; also known as a ...
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CNO Cycle
The CNO cycle (for carbon Carbon (from la, carbo "coal") is a with the C and 6. It is lic and —making four s available to form s. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three occur naturally, ...–nitrogen Nitrogen is the chemical element upright=1.0, 500px, The chemical elements ordered by link=Periodic table In chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science ...–oxygen Oxygen is the chemical element Image:Simple Periodic Table Chart-blocks.svg, 400px, Periodic table, The periodic table of the chemical elements In chemistry, an element is a pure substance consisting only of atoms that all have the same ...; sometimes called Bethe–Weizsäcker cycle after Hans Albrecht Bethe Hans Albrecht Bethe (; July 2, 1906 – March 6, 2005) was a German-American Nuclear physics, nuclear physicist w ...
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Oxygen
Oxygen is the chemical element In chemistry, an element is a pure Chemical substance, substance consisting only of atoms that all have the same numbers of protons in their atomic nucleus, nuclei. Unlike chemical compounds, chemical elements cannot be broken down into simp ... with the symbol A symbol is a mark, sign, or that indicates, signifies, or is understood as representing an , , or . Symbols allow people to go beyond what is n or seen by creating linkages between otherwise very different s and s. All (and ) is achieved th ... O and atomic number 300px, The Rutherford–Bohr model of the hydrogen atom () or a hydrogen-like ion (). In this model it is an essential feature that the photon energy (or frequency) of the electromagnetic radiation emitted (shown) when an electron jumps from one ... 8. It is a member of the chalcogen The chalcogens () are the chemical elements in group (periodic table), group 16 of the periodic table. This group is als ...
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Carbon
Carbon (from la, carbo "coal") is a with the C and 6. It is lic and —making four s available to form s. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three occur naturally, and being stable, while is a , decaying with a of about 5,730 years. Carbon is one of the . Carbon is the 15th , and the after , , and . Carbon's abundance, its unique diversity of s, and its unusual ability to form s at the temperatures commonly encountered on enables this element to serve as a common element of . It is the second most abundant element in the by mass (about 18.5%) after oxygen. The atoms of carbon can bond together in diverse ways, resulting in various . The best known allotropes are , , and . The of carbon vary widely with the allotropic form. For example, graphite is and black while diamond is highly . Graphite is soft enough to form a streak on paper (hence its name, from the verb "γράφειν" which ...
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Star
A star is an astronomical object In , an astronomical object or celestial object is a naturally occurring , association, or structure that exists in the . In , the terms ''object'' and ''body'' are often used interchangeably. However, an astronomical body or celestial body i ... consisting of a luminous spheroid A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric In mathematics, a quadric or quadric surface (quadric hypersurface in higher dimensions), is a generalization of conic sections (ellipse In math ... of plasma Plasma or plasm may refer to: Science * Plasma (physics), one of the four fundamental states of matter * Plasma (mineral) or heliotrope, a mineral aggregate * Quark–gluon plasma, a state of matter in quantum chromodynamics Biology * Blood plasma ... held together by its own gravity Gravity (), or gravitation, is a by which all things with or —including s, s, , and even —are attracted t ...
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