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Guilherme Mazui

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What is the Difference Between Absolute and Apparent Magnitude?

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The difference between absolute and apparent magnitude lies in the distance from which the brightness of a star is measured:

  • Absolute Magnitude: This is a measure of how bright a star would be if it were seen from a standard distance of 10 parsecs (32.58 light-years) away. It represents the star's intrinsic luminosity and is used to compare the inherent brightness of stars without the effect of distance.
  • Apparent Magnitude: This is the brightness of a star as seen from Earth. It is a measure of how luminous a star appears to an observer on Earth and is affected by the star's distance from Earth.

In summary, absolute magnitude is a measure of a star's intrinsic brightness when viewed from a standard distance, while apparent magnitude is a measure of a star's brightness as seen from Earth, which is affected by the star's distance.

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  • What is the Difference Between Absolute and Apparent Magnitude?
  • Comparative Table: Absolute vs Apparent Magnitude

    • Comparative Table: Absolute vs Apparent Magnitude

    The main difference between absolute and apparent magnitude lies in the distance of the object from Earth. Absolute magnitude is a measure of a star's true brightness, while apparent magnitude is how bright a star appears from Earth. Here is a table summarizing the differences:

    Feature Absolute Magnitude Apparent Magnitude
    Definition A measure of a star's intrinsic brightness A measure of how bright a star appears from Earth
    Distance Assumes a distance of 10 parsecs (approximately 32.6 light-years) from Earth Varies depending on the actual distance of the star from Earth
    Magnitude Indicates the star's true brightness, not affected by distance Indicates the star's brightness as seen from Earth, affected by distance
    Calculation To find a star's absolute magnitude (Mv), use the formula: Mv = m - 2.5 log (d/10)² To find a star's distance from its absolute and apparent magnitudes, use the formula: d = 10^(0.2*((m - Mv) / 5)) (Source:)

    The scale for both absolute and apparent magnitude is logarithmic, with a difference of 1 magnitude corresponding to a 2.512 times difference in brightness.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.