Other causes of valve disease include: 1  Deposits of calcium (calcification) in parts of the valve. 2  A floppy valve, which is a common cause of mild mitral valve regurgitation. 3  Some congenital heart problems. 4  Infection of the valve (infective endocarditis). 5  A complication of various uncommon diseases.
exists and is an alternate of . Castor is a variable star and also a quadruple star system, and has a spectral class of A1/A2 giving it a colour of white to white blue. Castor is a variable star and also a quadruple star system, and has a spectral class of A1/A2 giving it a colour of white to white blue. See link for more information.  <br /><br /> See link for more information. Castor is a variable star and also a quadruple star system, and has a spectral class of A1/A2 giving it a colour of white to white blue. <br /><br />
Figure 14.5 Variable Stars on HR Diagram Pulsating variable stars are found in the instability strip of the HR diagram. As a high-mass star evolves through the strip, it becomes a Cepheid variable.Low-mass horizontal-branch stars in the instability strip are RR Lyrae variables.igure 14.5 Variable Stars on HR Diagram Pulsating variable stars are found in the instability strip of the HR diagram. As a high-mass star evolves through the strip, it becomes a Cepheid variable.