Questions tagged [variable-star]

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Color index B-V of the dimming Betelgeuse

Using AAVSO light curve generator I have plotted V and B magnitudes of Betelgeuse in the past 150 days to see trend of B-V color index. If dust would be the cause of the recent drop in the star ...
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Does the current “fainting” of Betelgeuse show any spectral trends that differ from it's normal variability?

The Astronomers Telegrams #13341 The Fainting of the Nearby Red Supergiant Betelgeuse and #13365 Updates on the “Fainting” of Betelgeuse (both in December 2019) discuss the importance of measuring ...
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Large amplitude dipole pulsator

Consider a semiregular variable with amplitude of 1.5 mag. Is it possible to explain brightness variations by purely dipole pulsations?
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Is Betelgeuse is continually expelling material on the scale of the 2019/2020 event?

The AUGUST 13, 2020 Phys.org article Results from Hubble suggest that Betelgeuse's recent dimming was due to material ejected from the star says: ...the star's unexpected and significant dimming ...
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When we say a variable star is “fainting” does it mean something more or different than “dimming” or “fading”?

A comment below the question Does the current “fainting” of Betelgeuse show any spectral trends that differ from it's normal variability? suggests that "dimming" would be a better term, but I have a ...
1
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Why do these photometric observations of Betelgeuse look “quantized” in 0.1 magnitude steps?

The most interesting question related to this Will Kinney tweet would be what's going on with Betelgeuse? but I can't help but wonder why much but not all of the photometric data is clustered in ...
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19 views

Why are the W UMa variable subtypes labelled “A” and “W”?

The W Ursae Majoris variables (eclipsing contact binary stars) are divided into the A- and W-types. In systems of the A-type, the more massive component has the higher effective temperature, in ...