15 The Messenger 168 – June 2017 Magda Arnaboldi 1 Nausicaa Delmotte 1 Dimitri Gadotti 1 Michael Hilker 1 Gaitee Hussain 1 Laura Mascetti 2 Alberto Micol 1 Monika Petr-Gotzens 1 Marina Rejkuba 1 Jörg Retzlaff 1 Robert Ivison 1 Bruno Leibundgut 1 Martino Romaniello 1 1 ESO 2 TERMA GmbH, Europahaus, Darmstadt, Germany The ESO Public Surveys on VISTA serve the science goals of the survey teams while increasing the legacy value of ESO programmes, thanks to their homoge- neity and the breadth of their sky cover- age in multiple bands. These projects address a variety of research areas: from the detection of planets via micro- lensing, to stars, the Milky Way and Local Group galaxies, to extragalactic astronomy, galaxy evolution, the high- redshift Universe and cosmology. In 2015, as the frst generation of imaging surveys was nearing completion, a second call for Public Surveys was opened to defne a coherent scientifc programme for VISTA until the com- missioning of the wide-feld multi-fbre spectrograph, 4MOST, in 2020. This article presents the status of the Cycle 1 surveys as well as an overview of the seven new programmes in Cycle 2, including their science goals, coverage on the sky and observing strategies. We conclude with a forward look at the Cycle 2 data releases and the timelines for their release. Introduction ESO has operated two telescopes that are mostly dedicated to Public Surveys since 2010: namely, the 4-metre Visible and Infrared Survey Telescope for Astron- omy (VISTA; Sutherland et al., 2015) and the 2.6-metre VLT Survey telescope (VST; Arnaboldi et al., 1998; Capaccioli & Schipani, 2011). These provide coverage from the ultraviolet (0.33 micron) through to the Ks-band (2.15 microns). In 2012, Public Spectroscopic Surveys also started using the spectrographs Ultra- violet and Visual Echelle Spectrograph, UVES, GIRAFFE and the ESO Faint Object Spectrograph and Camera, EFOSC2. The spectroscopic surveys were further expanded in 2014 with the addition of two new surveys on Unit Telescope 3 (UT3) using the VIsible MultiObject Spec- trograph (VIMOS). As the frst cycle of ESO Public Surveys with VISTA approached its sixth year of successful telescope operations in 2015, ESO opened the call for submis- sion of letters of intent for a second cycle of Public Surveys to run until the end of 2020, the expected date for the decom- missioning of the VISTA InfraRed CAMera (VIRCAM). Thirteen letters of intent were submitted by the community by the deadline of October 2015; these involved more than thirteen Principal Investigators (PIs) and 517 co-investigators, with an oversubscription factor of over twice the total available observing time. The joint VISTA/VST Public Survey Panel (PSP) was asked to review these letters to iden- tify a well-balanced scienti fc programme for VISTA. An important consideration for the VISTA Cycle 2 Public Surveys was the exploration of scienti fc and observing parameter space that had not been covered by the previous surveys. These recommendations were passed to the Observing Programmes Committee (OPC) and the ESO Director General. In this article, we provide an overview of the status of the VISTA imaging surveys that started in 2010 and their impact in terms of data releases and refereed publications. We then describe the selec- tion process of the new surveys and pro- vide a summary of their science goals, observing strategies, and the content and timelines of their planned data releases. Looking further ahead, the construction and deployment of two wide-feld spec- trographs is foreseen: the Multi Object Optical and Near Infrared Spectrograph (MOONS; Cirasuolo et al., 2011) and the 4-metre Multi Object Spectroscopic Telescope (4MOST; de Jong, 2011) on the VLT and VISTA respectively. They have large multiplexing wide feld capabilities and extended wavelength coverage. These spectrographs will be used for follow-up studies of interesting candidates identifed via their colours and/or morpho- logical properties from the Public Surveys and/or space missions (for example, the ESA satellite, Gaia, and eROSITA). In the current ESO instrument plan, the 4MOST spectrograph will replace the wide feld near-infrared camera, VIRCAM, on VISTA, with commissioning being planned for the end of 2020. VISTA Cycle 1 surveys: time allocation and current status The frst cycle of approved VISTA Public Surveys includes six imaging projects 1 that began observations in April 2010. Figure 1 shows the completion fractions of the requested time in their observing plans with respect to time. An overview of each of the Cycle 1 surveys is given in Table 1 along with their full titles and acronyms; a more complete description of each of these surveys is presented in The Messenger 154 (2013). The overall time allocations for these sur- veys are between 1500 and 2200 hours, except for the VHS, which requires 4710 hours for completion. The VHS takes up 28 % of the allocated telescope time to date, while about 12 % goes to each one of the other surveys; additionally Chilean regular and other open-time programmes have been allocated 3 % and 4 % of time respectively. Figure 2 shows a pie chart summarising the time committed to the VISTA surveys between Periods 85 and 99, as a percentage of the total allocated telescope time. Based on statistics gathered over three years (from October 2012 to September 2015), the total execution time of suc- cessfully observed OBs from the VISTA Cycle 1 surveys is 2340 hours per year. The time for open and Chilean time amounts to about 6 % of the total time in that period. Thus, 2490 hours/year are available for successful observations with VISTA. In 2015, the projected observations for the VISTA Cycle 1 surveys showed that observing time would become availa- ble in certain right ascension (RA) ranges; hence the need to release a call for VISTA Cycle 2 Public Surveys. ESO Public Surveys at VISTA: Lessons learned from Cycle 1 Surveys and the start of Cycle 2 DOI: 10.18727/0722-6691/5020 Telescopes and Instrumentation