As announced in the Call for Proposals for Period 100, no science observations are foreseen with APEX from October 2017 to March 2018. This extended shutdown period is required to perform a number of major telescope maintenance activities, such as the replacement of the subreflector, the gearboxes and the shutter mechanism.
APEX Going Into Extended Shutdown Starting October 2017
The scheduled activities require the temporary de-installation of most APEX instruments, and their subsequent re-commissioning. These activities are essential to guarantee continued operation of APEX until the end of its extended lifetime, foreseen for 2022.
In order to mitigate the effect of this extended shutdown period on APEX users, the observations for ESO Period 100 will be started early, in late July, and will end on 2 October. No Director's Discretionary Time (DDT) observations with APEX will be possible between October 2017 and March 2018.