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According to https://en.wikipedia.org/wiki/UY_Scuti

Apparent magnitude (V) 8.29 - 10.56

Absolute magnitude (MV) −6.2

UY Scuti, being a variable star, obviously has variable apparent magnitude; however why is the absolute magnitude a single value? Am I missing something i.e. does this have anything to do with the way UY Scuti is variable for instance being enshrouded in dust, or is it simply a Wikipedia error?

A quick check of other pages also shows some inconsistencies:
https://en.wikipedia.org/wiki/W_Virginis (same as UY Scuti)

Absolute magnitude (MV) −3.0

https://en.wikipedia.org/wiki/Mira (absolute magnitude flagged as variable)

Absolute magnitude (MV) +0.99[7] (variable)

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    $\begingroup$ UV Scuti is a pulsating variable star; this means it cyclically expands and contracts back to its original size. I would reckon that its absolute magnitude remains the same, as it always emits the same amount of light; however, when it expands, this light is emitted by a larger surface area, so it appears dimmer. $\endgroup$
    – Pierre Paquette
    Commented Oct 1, 2022 at 4:49
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    $\begingroup$ True. I did a little more reading, and specially of the Wikipedia page about Cepheids and the one about en.wikipedia.org/wiki/Kappa%E2%80%93mechanism the κ-mechanism. The star’s opacity changes as it pulsates, so this will allow more or less light to filter through. This seems like a better explanation of why the star’s apparent brightness would change while the nuclear reactions in its core don’t change (hence it maintains the same energy production). $\endgroup$
    – Pierre Paquette
    Commented Oct 1, 2022 at 6:44
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    $\begingroup$ Absolute magnitude can be computed from apparent magnitude and distance, so, if the apparent magnitude changes, so should the absolute magnitude. I think this is just a glitch. You can use the given range of apparent magnitudes and the distance to find what the corresponding absolute magnitude would be and see where -6.2 falls in that range. $\endgroup$
    – Barry Carter
    Commented Oct 1, 2022 at 11:00
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    $\begingroup$ I agree with @BarryCarter. This is just yet another case of wikipedia being wikipedia. It is not a reliable source of information. $\endgroup$
    – David Hammen
    Commented Oct 1, 2022 at 18:22
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    $\begingroup$ @barry It's not so easy because there is significant extinction due to dust. The -6.2 value seems to be an estimate of the average luminosity made in about 1970, using IR observations (that are less affected by dust), adjusted to an M_v value using a special model. There is considerable uncertainty in the value, but it is undoubtedly a huge and powerful supergiant star. $\endgroup$
    – James K
    Commented Oct 1, 2022 at 20:33

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