For Herschel, the last weeks before Christmas 2008 were devoted to the final series of thermal balance and thermal vacuum (TBTV) tests under simulated in-flight conditions. These involved the spacecraft and the payload and were successfully completed by December 20th. During the TBTV tests, the second system operations verification test (SOVT-2) also took place from December 13 to 19 (the SOVT-1 was performed on September 6 thru 10, 2008). The SOVT-2 involved the entire ground segment and included several days of operations of the spacecraft from the mission control center in ESOC, with operational tests of all the Herschel instruments. Following the completion of all test activities Herschel was kept inside the LSS over the end-of-year holidays. In the first week of January, the LSS top lid was removed and the spacecraft prepared for removal from the LSS.
On January 8, the Herschel spacecraft was secured to an overhead crane, through the Herschel Vertical Lifting Device (HVLD), which carefully lifted the spacecraft out of the LSS through the top opening of the LSS chamber (Photo, right). Having cleared the LSS chamber, the spacecraft was manoeuvred forwards and then carefully lowered onto a ground support stand in front of the LSS inside the cleanroom.
After decoupling the HVLD from the crane, another crane was attached to it which later hoisted the spacecraft up again to transfer it to the other side of the cleanroom (Photo, left). There, Herschel was lowered onto the real flight adapter of the Ariane 5 launcher for a fit check well before launch in April this year. After completion of this fit check the spacecraft was transported to another cleanroom in the ESTEC facilities, where the Herschel spacecraft will complete a sequence of final functional tests before its departure for the launch site in Kourou.
