Star
A star is a luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun. Other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth. Historically, the most prominent stars were grouped into constellations and asterisms, and the brightest stars gained proper names. Extensive catalogues of stars have been assembled by astronomers, which provide standardized star designations.
For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. Once the hydrogen in the core of a star is nearly exhausted, almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime and, for some stars, by supernova nucleosynthesis when it explodes. Near the end of its life, a star can also contain degenerate matter. Astronomers can determine the mass, age, metallicity (chemical composition), and many other properties of a star by observing its motion through space, luminosity, and spectrum respectively. The total mass of a star is the principal determinant of its evolution and eventual fate. Other characteristics of a star, including diameter and temperature, change over its life, while the star's environment affects its rotation and movement. A plot of the temperature of many stars against their luminosities, known as a Hertzsprung–Russell diagram (H–R diagram), allows the age and evolutionary state of a star to be determined.
Staré
Staré is a village and municipality in Michalovce District in the Kosice Region of eastern Slovakia.
History
In historical records the village was first mentioned in 1221.
Geography
The village lies at an altitude of 107 metres and covers an area of 6.234 km². The municipality has a population of about 700 people. The name was taken from grof Staray.
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Coordinates: 48°52′N 21°52′E / 48.867°N 21.867°E / 48.867; 21.867
Growth–share matrix
The growth–share matrix (aka the product portfolio, BCG-matrix, Boston matrix, Boston Consulting Group analysis, portfolio diagram) is a chart that was created by Bruce D. Henderson for the Boston Consulting Group in 1970 to help corporations to analyze their business units, that is, their product lines. This helps the company allocate resources and is used as an analytical tool in brand marketing, product management, strategic management, and portfolio analysis. Analysis of market performance by firms using its principles has recently called its usefulness into question.
Overview
To use the chart, analysts plot a scatter graph to rank the business units (or products) on the basis of their relative market shares and growth rates.
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