1. Roy,A.E.,OrbitalMotion,3rded.,InstituteofPhysicsPublishing,Philadelphia,1988,Chap.5. Figure 5. The integrated telescope and SIB in (a) the launch configuration, showing the shortened optical tube enclosure in blue, and (b) the operational configuration, showing the optical tube enclosure extendedandthe doorsopening. The spacecraft/instrument busandpayloadadapter are shownin red.