Double star as comp star for CH Cyg. Is the companion variable?
I noticed that SAO 31586, which is used as the comparison star for PEP observations of CH Cyg is a double star with a component about 7 arc seconds away, and a magnitude of about 10. The companion seems bright enough that there could be some error depending upon where in the apeture the star is placed. Is it possible the companion has brightened since it SAO 31586 was choosen as the comp star?