A planned IT Maintenance will take place at ESO between Saturday, 11 April 2026 at 08:00 CEST and Sunday, 12 April 2026 at 24:00 CEST. From 08:00 CEST on Saturday all ESO services including p1, p2, the Operations Helpdesk and the Scientific Archive could be subject to intermittent outages. We apologize for any inconvenience.
OB run-time failure policy
Although ESO carefully reviews Service Mode Observation Blocks (OBs) before they are scheduled at the telescope, it is impossible to detect every OB problem until it is actually executed.
If an OB fails to execute due to an error introduced by the user (as for example if the user entered wrong target coordinates), ESO reserves the right to charge the respective observing programme for the time lost during night operations. Time charged will include any telescope time used to investigate why OB execution failed.
For Service Mode observations time lost due to failures caused by ESO (e.g. instrument malfunction) will not be charged to the user. Whenever possible, these OBs will be re-executed as time, conditions, and overall priority permit.