Greidy Castellanos working for the ELT's Phasing and Diagnostic Station

Greidy Castellanos, Electronic Technician at ESO, is wiring up a circuit breaker, an electrical device that protects electrical circuits from damage when there is an excessive electrical current. The circuit breaker is being connected to one of the Phasing and Diagnostic Station cabinets that will be part of ESO's Extremely Large Telescope (ELT). As the name indicates, these cabinets will be used for general diagnostics, but will also ensure the ELT's phasing process. This process is extremely delicate, as it requires that all 798 segments of the ELT's primary mirror act together, creating one single giant mirror.