Papal cross Papal cross The papal cross is a Christian cross, which serves as an emblem for the office of the Pope in ecclesiastical heraldry. It is depicted as a staff with three horizontal bars near the top, in diminishing order of length as the top is approached. The cross is thus analogous to the two-barred archiepiscopal cross used in heraldry to indicate an archbishop, and seems to have been used precisely to indicate an ecclesiastical rank still higher than that of archbishop. In the past, this design of the cross was often used in ecclesiastical heraldry as a distinctive mark of
Horizontal branch occur for 10% or more of post-AGB stars, although it is thought that only particularly late thermal pulses create extreme horizontal-branch stars, after the planetary nebular phase and when the central star is already cooling towards a white dwarf. Globular cluster CMDs generally show horizontal branches that have a prominent gap in the HB. This gap in the CMD incorrectly suggests that the cluster has no stars in this region of its CMD. The gap occurs at the instability strip, so many stars in this region pulsate. These pulsating horizontal-branch stars are known as RR Lyrae variable stars and they