VISTA

VISTA (for Visible and Infrared Survey Telescope for Astronomy) is a 4.1-meter reflector telescope at the Paranal Observatory in Chile operated by the European Southern Observatory (ESO). It saw first light in 2009. Over its first years, three fourths of its time was be dedicated to public surveys:

• VIKING, for VISTA Kilodegree Infrared Galaxy Survey.
• UltraVISTA.
• VMC, for VISTA Magellanic Survey.
• VVV, for VISTA Variables in the Via Lactea Survey.
• VHS, for VISTA Hemispheric Survey.
• VIDEO, for VISTA Deep Extragalactic Observations Survey, which includes the CFHTLS-D1 survey field.

VISTA's name implies optical capability, able to host visible-light instruments, but initially it had just one instrument, VIRCAM (Vista IR camera), which is substantial, and I suspect that its size precluded any other instruments at the same time. Subsequently, a new fiber-fed optical multi-object spectrograph (2400 fibers) called 4MOST has been installed and operation is intended to begin during the first quarter of 2025.