hellojoey

the definition of a star is that it is in a fixed position. no movement in the star field. so why does betelgeuse have a differnt luminosity thoroughout the years? at a typical mean of about .5 magnitude it varies up and down during a decade in diameter. could it be a planet like our own, that we are in similar orbit paths that it was always thought a star? consider saturn which has about an identical magnitude. what is the slight movement of betelguese mean? its very bizarre.