- Giant star (Wikipedia)
A giant star has a substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzsprung–Russell diagram and correspond to luminosity classes II and III. The terms giant and dwarf were coined for stars of quite different luminosity despite similar temperature or spectral type (namely K and M) by Ejnar Hertzsprung in 1905 or 1906.
- Delta Scuti (stars.astro.illinois.edu)
Modest Delta Scuti (in Scutum, the Shield), shining only at 5th magnitude (4.71) in a relatively obscure modern constellation best known for its placement in the Milky Way, stands out as the prototype of one of these, the pulsating “Delta Scuti stars,” of which Caph in Cassiopeia is the brightest.
- Delta Scuti (Wikipedia)
Delta Scuti, Latinized from δ Scuti, is a variable star in the southern constellation Scutum. With an apparent visual magnitude that fluctuates around 4.72, it is the fifth-brightest star in this small and otherwise undistinguished constellation. Analysis of the parallax measurements place this star at a distance of about 199 light-years (61 parsecs) from Earth. It is drifting closer with a radial velocity of −45 km/s.