For six months, almost the whole ALMA site has been shut down with no power, water treatment, or running water. Only a single piece of key equipment, the hydrogen maser, is still powered and checked daily as one of the tasks of the ALMA Caretaker Teams, the teams who have ensured the safety and security of the ALMA Observatory through the shutdown. With the improving pandemic situation in Chile, ALMA is now scheduled to begin the long process of recovering the telescope array in the Atacama on October 1st, 2020, starting with preparation of the ALMA Operations Support Facility (OSF) at 2900 metres for the return of staff and contractors.
ALMA Starts the Process of Recovering the Telescope Array
The road to recovery of operations and ultimately science observations has been carefully planned. It is difficult to predict the exact timeline since several aspects of the plan depend on prevailing conditions beyond the observatory's control. The following describes the current plan of activities and schedule for the return of ALMA to science operations.
The ALMA Observatory has developed an extensive set of enhanced safety protocols related to managing the risk posed by the virus while covering all activities as the recovery of operations progresses. First, preparing the OSF for the return of staff and contractors, followed by moving back into the OSF and the use of the OSF facilities, before the process of restarting the Array Operations Site (AOS) at 5000 metres begins. Each of the phases will take time and patience, establishing and working within new safety protocols while stabilizing systems that have been shut down for six months, an unprecedented situation in the history of the Observatory.
The current restart plan requires about 80 days to reach the antenna power-up milestone, assuming there are no major repairs needed, or changes in the schedule due to impacts of the pandemic. The time needed to recover sufficient antennas for science observations is highly uncertain. Nevertheless, the goal is to have antennas collecting data and verifying the observing systems after approximately 100 days. Whether this is a handful, or many antennas, remains difficult to predict. This implies that January is the earliest time when there may be enough functional antennas and cooled receivers to attempt the first science observations. In addition, regular February maintenance is anticipated to go ahead as the weather is typically poor for science, and critical power infrastructure maintenance must be done at a time of year that minimizes the impact on science operations.
Status updates will continue to be provided at least monthly, as the recovery of operations progresses. Specific capabilities and potential science observing dates will be identified after the status of antennas and other critical systems has been better understood.
The plan described above assumes that the situation in Chile and worldwide continues to improve. Regular monitoring of the pandemic evolution is performed each week. These reviews could result in advancing to the next phase in the recovery plan, maintaining the current phase, or even taking a step backwards if necessary.
The European ALMA Regional Centre invites all European ALMA users to a short virtual community assembly on 8 October at 10:00 AM CEST. At this community meeting, which can be accessed at this link, users will be updated on the time line for recovery, and any questions on ALMA projects or support from the European ARC network will be answered. As always, the ALMA Regional Centres continue to provide support to their respective communities. For any questions, comments or concerns related to the situation at ALMA, please contact the ALMA Helpdesk.