A Delta Scuti variable is a variable star which exhibits variations in its luminosity due to both radial and non-radial pulsations of the star's surface. Typical brightness fluctuations are from 0.003 to 0.9 magnitudes in V over a period of a few hours, although the amplitude and period of the fluctuations can vary greatly. The stars are usually A0 to F5 type giant or main sequence stars. Most stars are of almost constant luminosity. ... Luminosity has different meanings in several different fields of science. ... In science, a magnitude is the numerical size of something: see orders of magnitude. ... Amplitude is a nonnegative scalar measure of a waves magnitude of oscillation, that is, magnitude of the maximum disturbance in the medium during one wave cycle. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... Giant star is a star that has stopped fusing hydrogen in its core. ... Hertzsprung-Russell diagram The main sequence of the Hertzsprung-Russell diagram is the curve where the majority of stars are located in this diagram. ...

The prototype of these sorts of variable stars is Delta Scuti, which exhibits brightness fluctuations from +4.60 to +4.79 in apparent magnitude with a period of 4.65 hours. Other well known Delta Scuti variables include Vega (α Lyrae), Denebola (β Leonis) and β Cassiopeiae. Delta Scuti (δ Sct / δ Scuti) is a triple star system in the constellation Scutum. ... // Headline text HEY!! HOW ARE YOU ALL?? Its nice of you to come read this page. ... Vega (α Lyr / α Lyrae / Alpha Lyrae) is a white main sequence star approximately 25. ... Denebola (β Leo / β Leonis / Beta Leonis) is the second brightest star in the constellation Leo. ... Beta Cassiopeiae (β Cas / β Cassiopeiae) is a star in the constellation Cassiopeia. ...

References

Samus N.N., Durlevich O.V., et al. Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.)