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Highlights include:

Patat, F., Kerzendorf, W. et al.: The Distributed Peer Review Experiment
Goddi, C., Crew, G. et al.: First M87 Event Horizon Telescope Results and the Role of ALMA
Schinnerer, E., Leroy, A. et al.: The Physics at High Angular resolution in Nearby GalaxieS (PHANGS) Surveys
Ventura, L., Melo, C. et al.: Total Solar Eclipse Over La Silla

ADS BibCode: 2019Msngr.177....3P

Patat, F., Kerzendorf, W., Bordelon, D., Van de Ven, G., Pritchard, T.

All large, ground- and space-based astronomical facilities serving wide communities face a similar problem: in many cases the number of applications they receive in response to each call exceeds 1000. This poses a serious challenge to running an effective selection process under the classic peer-review paradigm, in which the proposals are assigned to pre-allocated panels with fixed compositions. Although, in principle, one could increase the size of the time allocation committee, this creates logistic and financial problems which place a practical limit on its maximum size, making this solution unviable beyond a certain volume of applications. For this reason, alternative solutions must be sought. One of these is the so-called Distributed Peer Review (DPR) in which, by submitting a proposal, the Principal Investigators (PIs) agree both to act as reviewers and to have their proposal reviewed by their peers. In this article we report the results of a DPR experiment run by ESO in Period 103, in parallel with the regular review by the Observing Programmes Committee (OPC).

ADS BibCode: 2019Msngr.177...14C

Coccato, L., Freudling, W., Smette, A., Sani, E., Escartin, J., Jung, Y., Bazin, G.

The presence of strong absorption lines in the atmospheric transmission spectrum affects spectroscopic observations, in particular those in the near- and mid-infrared. Therefore, there is the need to correct scientific observations for this effect, a process known as telluric correction. The use of a detailed model of the atmospheric transmission spectrum brings several advantages over the method of empirically deriving corrections using observations of a telluric standard star. In this paper, we discuss and compare the two methods applied to K-band Multi-Object Spectrograph (KMOS) observations and show the improvements in the quality of the final products obtained by implementing the modelling technique offered by the ESO molecfit sky tool.

ADS BibCode: 2019Msngr.177...19G

Gonté, F., Abad, J., Abuter, R., Aller Carpentier, E., Alonso, J., Andofalto, L., Barriga, P., Berger, J., Beuzit, J., Blanchard, I., Bonnet, H., Bourdarot, G., Bourget, P., Brast, R., Bristow, P., Caniguante, L., Cerda, S., Cid, C., Correa, A., Cottalorda, E., Courtney-Barrer, B., Darré, P., Delabre, B., Delboulbé, A., Dembet, R., Donaldson, R., Dorn, R., Dupeyron, J., Dupuy, C., Egner, S., Eisenhauer, F., Faundez, L., Fedrigo, E., Fischer, G., Frank, C., Fuenteseca, E., Gitton, P., Guerlet, T., Guieu, S., Gutierrez, P., Haguenauer, P., Haimerl, A., Haubois, X., Heritier, C., Huber, S., Hubin, N., Jolley, P., Jocou, L., Kirchbauer, J., Kolb, J., Kosmalski, J., Krempl, P., La Fuente, C., Le Bouquin, J., Le Louarn, M., Lilley, P., Lopez, B., Lopez, M., Magnard, Y., Marchetti, E., Mclay, S., Meilland, A., Meister, A., Mérand, A., Moulin, T., Pasquini, L., Paufique, J., Percheron, I., Pettazzi, L., Pfuhl, O., Phan, D., Pino, A., Pirani, W., Quentin, J., Rakich, A., Ramirez, A., Ridings, R., Riedel, M., Reyes, J., Rochat, S., Sanchez, J., Santos Tomás, G., Schmid, C., Shchekaturov, P., Schuhler, N., Seidel, M., Soenke, C., Stadler, E., Stephan, C., Suárez, M., Todorović, M., Valdes, G., Verinaud, C., Woillez, J., Zins, G., Zúñiga-Fernández, S.

NAOMI was developed by a consortium composed of IPAG and ESO. Its Provisional Acceptance Chile review was held in April 2019. The NAOMI systems that have been installed on the Auxiliary Telescopes make the Very Large Telescope Interferometer (VLTI) and its instruments much less dependent on the atmospheric and dome seeing conditions. NAOMI increases the interferometer’s operability and improves the performance of its instruments and, very early on, was identified as being critical to the VLTI. In this article, we review the project, describe its principles and architecture, and offer a preview of the improvements it brings to VLTI instruments.

ADS BibCode: 2019Msngr.177...24G

Goddi, C., Crew, G., Impellizzeri, V., Martí-Vidal, I., Matthews, L., Messias, H., Rottmann, H., Alef, W., Blackburn, L., Bronzwaer, T., Chan, C., Davelaar, J., Deane, R., Dexter, J., Doeleman, S., Falcke, H., Fish, V., Fraga-Encinas, R., Fromm, C., Herrero-Illana, R., Issaoun, S., James, D., Janssen, M., Kramer, M., Krichbaum, T., De Laurentis, M., Liuzzo, E., Mizuno, Y., Moscibrodzka, M., Natarajan, I., Porth, O., Rezzolla, L., Rygl, K., Roelofs, F., Ros, E., Roy, A., Shao, L., van Langevelde, H., van Bemmel, I., Tilanus, R., Torne, P., Wielgus, M., Younsi, Z., Zensus, J., The Event Horizon Telescope collaboration

In April 2019, the Event Horizon Telescope (EHT) collaboration revealed the first image of the candidate super- massive black hole (SMBH) at the centre of the giant elliptical galaxy Messier 87 (M87). This event-horizon-scale image shows a ring of glowing plasma with a dark patch at the centre, which is interpreted as the shadow of the black hole. This breakthrough result, which represents a powerful confirmation of Einstein’s theory of gravity, or general relativity, was made possible by assembling a global network of radio telescopes operating at millimetre wavelengths that for the first time included the Atacama Large Millimeter/submillimeter Array (ALMA). The addition of ALMA as an anchor station has enabled a giant leap forward by increasing the sensitivity limits of the EHT by an order of magnitude, effectively turning it into an imaging array. The published image demonstrates that it is now possible to directly study the event horizon shadows of SMBHs via electromagnetic radiation, thereby transforming this elusive frontier from a mathematical concept into an astrophysical reality. The expansion of the array over the next few years will include new stations on different continents — and eventually satellites in space. This will provide progressively sharper and higher-fidelity images of SMBH candidates, and potentially even movies of the hot plasma orbiting around SMBHs. These improvements will shed light on the processes of black hole accretion and jet formation on event-horizon scales, thereby enabling more precise tests of general relativity in the truly strong field regime.

ADS BibCode: 2019Msngr.177...36S

Schinnerer, E., Leroy, A., Blanc, G., Emsellem, E., Hughes, A., Rosolowsky, E., Schruba, A., Bigiel, F., Escala, A., Groves, B., Kreckel, K., Kruijssen, D., Lee, J., Meidt, S., Pety, J., Sanchez-Blazquez, P., Sandstrom, K., Usero, A., Barnes, A., Belfiore, F., Bešlić, I., Chandar, R., Chatzigiannakis, D., Chevance, M., Congiu, E., Dale, D., Faesi, C., Gallagher, M., Garcia-Rodriguez, A., Glover, S., Grasha, K., Henshaw, J., Herrera, C., Ho, I., Hygate, A., Jimenez-Donaire, M., Kessler, S., Kim, J., Klessen, R., Koch, E., Lang, P., Larson, K., Le Reste, A., Liu, D., McElroy, R., Nofech, J., Ostriker, E., Pessa Gutierrez, I., Puschnig, J., Querejeta, M., Razza, A., Saito, T., Santoro, F., Stuber, S., Sun, J., Thilker, D., Turner, J., Ubeda, L., Utreras, J., Utomo, D., van Dyk, S., Ward, J., Whitmore, B.

A major advance in understanding the process of star formation will come from charting the connections between cold (molecular) gas and young stars on the scale of individual molecular clouds, HII regions, and star clusters. For the first time, the ESO facilities ALMA and MUSE, in combination with HST, offer the opportunity to survey the properties of these regions and clusters across a large sample of galaxies, capturing the range of diverse galactic environments found in the local universe. Guided by theoretical models and simulations, the PHANGS collaboration has begun an endeavour which aims to reveal the physical processes controlling the process of star formation in galaxies.

ADS BibCode: 2019Msngr.177...43V

Ventura, L., Melo, C., Christensen, L., Lyubenova, M., Comerón, F.

On Tuesday 2 July 2019, in the late afternoon, a total solar eclipse took place over ESO’s La Silla Observatory; totality lasted 1 minute and 52 seconds. For this very special event, ESO decided to open the doors of the observatory to the public, providing over one thousand visitors with a unique vantage point from which to witness this spectacular natural phenomenon.

ADS BibCode: 2019Msngr.177...47C

Christensen, L., Ávila, G., Baouchi, W., Boer, M., Le Borgne, J., Buil, C., Castillo-Fraile, M., Denoux, E., Desnoux, V., Elmore, D., Eymar, L., Fisher, R., Guirao, C., Klotz, A., Klotz, A., Lecubin, J., Motl, K., Pérez, D., Pérez-Ayúcar, M., van Reeven, W., Regal, X., Richaud, Y., Sautile, R., Santerne, A., Wellington, R., Wellington, T., Yanamandra-Fisher, P., Zender, J.

Total solar eclipses are rare phenomena, only occurring in a specific location once every 360 years on average. Historically, total solar eclipses have only been observed twice from large professional observatories, allowing specific science experiments to take place. On this occasion, ESO invited nearly 25 scientists, communicators and educators to observe and document the eclipse and benefit from La Silla’s clear skies and its infrastructure and resources. This article presents an overview of these various activities.

ADS BibCode: 2019Msngr.177...54D

Dennefeld, M., Koutchmy, S., Sèvre, F., Fathivavsari, H., Auchère, F., Baudin, F., Abdi, S., Sinclaire, P., Saviane, I., Labraña, F., Schmidtobreick, L.

ADS BibCode: 2019Msngr.177...56S

Sani, E., Hilker, M., Coccato, L., Ramsay, S., Evans, C., Rodrigues, M., Schmidtobreick, L., Sharples, R.

The K-band Multi-Object Spectrograph (KMOS) is one of the second-generation instruments at the VLT, and has been operating for five years. To celebrate this anniversary this workshop brought together astronomers to present scientific results from KMOS and complementary instruments. The topics ranged from star formation in the Galactic centre, to stellar populations in globular clusters, to galaxy formation and evolution at various redshifts, and feedback from active galactic nuclei (AGN). Another goal of the workshop was to assess the impact of KMOS on its core science goals and to develop new strategies and programmes, also in light of future integral field unit (IFU) instruments. About 60 researchers from the astronomical community and members of the Instrument Operations Team participated in the workshop and discussed the above topics; these discussions served to identify the highest priority improvements that could increase the scientific return of KMOS in the future.

ADS BibCode: 2019Msngr.177...61L

Liske, J., Mainieri, V.

The 4-metre Multi-Object Spectroscopic Telescope (4MOST) is a state-of-the-art, high-multiplex, fibre-fed, optical spectroscopic survey facility currently under construction for ESO’s 4-metre Visible and Infrared Survey Telescope for Astronomy (VISTA). During the first five years of operation 4MOST will be used to execute a comprehensive programme of both Galactic and extragalactic Public Surveys, and 30% of the observing time during this period will be available to the community. The purpose of this workshop was to prepare the ESO community for this exciting scientific opportunity.

ADS BibCode: 2019Msngr.177...64M

Mroczkowski, T., De Breuck, C., Kemper, C.

The Atacama Large Millimeter/Submillimeter Array (ALMA) is the most sensitive observatory spanning millimetre and submillimetre wavelengths. To maintain this position, however, a vibrant and concerted development programme is necessary. Since each partner region in ALMA conducts its own development programme, we hosted an international workshop at ESO to promote further cross-regional discussion of our parallel development efforts. As we describe here, an overriding goal for this was to align our development activities with the goals of the 2030 ALMA development roadmap — a report recently produced by ALMA to provide guidance on what directions we want the ALMA observatory to go in, and how to get there.

ADS BibCode: 2019Msngr.177...67M

Mérand, A., Leibundgut, B.

This four-day workshop offered a forum to discuss the scientific future of the VLT and VLTI. Overview talks of some of the main scientific topics for the next decade were followed by presentations on the most important facilities operating in 2030. Several instrument concepts and ideas were presented which would signifantly enhance the current VLT and VLTI capabilities. The workshop discussions are the basis for the plans for the VLT after 2025.

ADS BibCode: 2019Msngr.177...70E

ADS BibCode: 2019Msngr.177...71E

Jethwa, P., Oikonomou, F.

ADS BibCode: 2019Msngr.177...74H

ADS BibCode: 2019Msngr.177...75E

The Messenger Issue 177