The Messenger

The Messenger is ESO’s journal for science and technology. It serves as a link between ESO and its broad astronomical community by providing information about scientific, technical, and other developments. It also delivers relevant news about astronomy and astrophysics to a broader public, including policy-makers, government officials, journalists, teachers, and amateur astronomers, as well as to interested scientists from other fields.

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Issue 174
Messenger Issue 174

The Messenger Issue 174

Highlights include:

  • Jehin, E., Gillon, M. et al.: The SPECULOOS Southern Observatory Begins its Hunt for Rocky Planets
  • Andrews, S., Huang, J. et al.: ALMA Observations of the Epoch of Planet Formation
  • Förster Schreiber, N., Wilman, D. et al.: Witnessing the Early Growth and Life Cycle of Galaxies with KMOS3D
  • Barcons, X., Spyromilio, J.: Riccardo Giacconi (1931–2018)

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Past Issues
Messenger Issue 191
2023Issue 191
Messenger Issue 190
2023Issue 190
Messenger Issue 189
2022Issue 189
Messenger Issue 188
2022Issue 188
Messenger Issue 187
2022Issue 187
Messenger Issue 186
2022Issue 186
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2021Issue 185
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Messenger Issue 183
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Messenger Issue 175
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Messenger Issue 173
2018Issue 173
Messenger Issue 172
2018Issue 172
Table of Content No. 174 | 2018
Telescopes and Instrumentation
Jehin, E., Gillon, M. et al.
The SPECULOOS Southern Observatory Begins its Hunt for Rocky Planets
ADS BibCode: 2018Msngr.174....2J
Jehin, E., Gillon, M., Queloz, D., Delrez, L., Burdanov, A., Murray, C., Sohy, S., Ducrot, E., Sebastian, D., Thompson, S., McCormac, J., Almleaky, Y., Burgasser, A., Demory, B., de Wit, J., Barkaoui, K., Pozuelos, F., Triaud, A., Grootel, V.
The SPECULOOS Southern Observatory (SSO), a new facility of four 1- metre robotic telescopes, began scientific operations at Cerro Paranal on 1 January 2019. The main goal of the SPECULOOS project is to explore approximately 1000 of the smallest (≤ 0.15 R), brightest (Kmag ≤ 12.5), and nearest (d ≤ 40 pc) very low mass stars and brown dwarfs. It aims to discover transiting temperate terrestrial planets well-suited for detailed atmospheric characterisation with future giant telescopes like ESO’s Extremely Large Telescope (ELT) and the NASA James Webb Telescope (JWST). The SSO is the core facility of SPECULOOS. The exquisite astronomical conditions at Cerro Paranal will enable SPECULOOS to detect exoplanets as small as Mars. Here, we briefly describe SPECULOOS, and present the features and performance of the SSO facility.

de Wit, W., Wittkowski, M. et al.
The Life and Times of AMBER: The VLTI’s Astronomical Multi-BEam combineR
ADS BibCode: 2018Msngr.174....8W
de Wit, W., Wittkowski, M., Rantakyrö, F., Schöller, M., Mérand, A., Petrov, R., Weigelt, G., Malbet, F., Massi, F., Kraus, S., Ohnaka, K., Millour, F., Lagarde, S., Haubois, X., Bourget, P., Percheron, I., Berger, J., Richichi, A.
The sharpest images on Paranal are produced by the beam-combining instruments of the Very Large Telescope Interferometer (VLTI). Currently, the VLTI is close to completing a transitional period, moving away from the first generation of instruments (AMBER, MIDI) and offering new instruments and subsystems to the community. In this article, we report on the life and achievements of the recently decommissioned, near-infrared beam combiner instrument AMBER, the most prolific optical interferometric instrument to date.

Möller, T., Schilke, P. et al.
Modelling Data in CASA
ADS BibCode: 2018Msngr.174...14M
Möller, T., Schilke, P., Hogerheijde, M., Stewart, I., Schaaf, R., Harsono, D.
The Common Astronomy Software Applications (CASA) package provides a powerful tool for post-processing Atacama Large Millimeter/submillimeter Array (ALMA) and Karl G. Jansky Very Large Array (VLA) observations, but contains only rudimentary functions for modelling the data. In order to derive physical parameters as well as information on the location and the kinematics of the emitting gas, modelling of the observed data is inescapable. Such modelling can take the form of inference — where physical parameters are inferred from the data — or forward modelling — where model calculations are used to produce synthetic observations for comparison with data. We present two interfaces that allow the use of modelling tools for both flavours from within CASA: the eXtended CASA Line Analysis Sofware Suite (XCLASS); and Adaptable Radiative Transfer Innovations for Submillimeter Telescopes (ARTIST).

Astronomical Science
Andrews, S., Huang, J. et al.
ALMA Observations of the Epoch of Planet Formation
ADS BibCode: 2018Msngr.174...19A
Andrews, S., Huang, J., Pérez, L., Isella, A., Dullemond, C., Kurtovic, N., Guzmán, V., Carpenter, J., Wilner, D., Zhang, S., Zhu, Z., Birnstiel, T., Bai, X., Benisty, M., Hughes, A., Öberg, K., Ricci, L.
Planetary systems form in the discs of gas and dust that orbit young stars. In the past few years, observations of these discs at (sub-)millimetre wavelengths with very fine angular resolution have started to uncover the hallmarks of small-scale substructures in the spatial distributions of their pebble-sized particles. These are some of the fundamental signatures of the planet formation epoch, since they trace localised concentrations of material that facilitate the formation of much larger planetary building blocks, and may themselves be created by young planets interacting with their birth environments.

Evans, C., Castro, N. et al.
A First Spectroscopic Census of the Dwarf Galaxy Leo P
ADS BibCode: 2018Msngr.174...24E
Evans, C., Castro, N., Gonzalez, O., Garcia, M., Bastian, N., Cioni, M., Clark, S., Davies, B., Ferguson, A., Kamann, S., Lennon, D., Patrick, L., Vink, J., Weisz, D.
A longstanding quest in studies of luminous, massive stars has been to understand the role of environment on their evolution. The abundance of metals in their atmospheres has a significant impact on their physical properties, strongly influencing the feedback they have on their surroundings and the nature of their explosive deaths. To date we have been unable to study massive stars with metallicities below 10% that of the Sun. The low oxygen abundance (3% solar) and relative proximity (~1.6 Mpc) of Leo P, a low-luminosity dwarf galaxy discovered in 2013, provides a tantalising opportunity to investigate massive stars with near-primordial compositions. Here we introduce observations of Leo P with the Multi Unit Spectroscopic Explorer (MUSE) instrument on the VLT, which have revealed its spectroscopic content for the first time.

Förster Schreiber, N., Wilman, D. et al.
Witnessing the Early Growth and Life Cycle of Galaxies with KMOS3D
ADS BibCode: 2018Msngr.174...28S
Förster Schreiber, N., Wilman, D., Wisnioski, E., Fossati, M., Mendel, J., Bender, R., Genzel, R., Beifiori, A., Belli, S., Brammer, G., Burkert, A., Chan, J., Davies, R., Davies, R., Fabricius, M., Galametz, A., Herrera-Camus, R., Lang, P., Lutz, D., Momcheva, I., Naab, T., Nelson, E., Price, S., Renzini, A., Saglia, R., Seitz, S., Shimizu, T., Sternberg, A., Tacconi, L., Tadaki, K., Übler, H., van Dokkum, P., Wuyts, S.
Near-infrared integral field unit (IFU) spectrographs are powerful tools for investigating galaxy evolution. We report on our recently completed multi- year KMOS3D survey of Hα, [N II] and [SII] line emission of galaxies at redshift z ~ 0.7–2.7 with the K-band Multi-Object Spectrograph (KMOS) at the Very Large Telescope (VLT). With deep observations of 745 targets spanning over two orders of magnitude in galaxy mass, five billion years of cosmic time, and all levels of star formation, KMOS3D provides an unparalleled population-wide census of spatially-resolved kinematics, star formation, outflows and nebular gas conditions. The dataset sheds new light on the physical mechanisms driving the early growth and lifecycle of galaxies, and provides a rich legacy for the astronomical community.

Bulla, M., Covino, S. et al.
Shedding Light on the Geometry of Kilonovae
ADS BibCode: 2018Msngr.174...34B
Bulla, M., Covino, S., Patat, F., Kyutoku, K., Maund, J., Tanaka, M., Toma, K., Wiersema, K., D’Avanzo, P., Higgins, A., Mundell, C., Palazzi, E.
We present the first results of a campaign aimed at characterising the linear polarisation signals and thus the geometry of binary neutron star mergers (i.e., kilonovae). We carried out the first polarimetric observations of a kilonova called AT 2017gfo, using the FOcal Reducer/low dispersion Spectrograph 2 (FORS2). We predicted for the first time the polarisation signatures expected from kilonovae and highlighted the best strategy to detect linear polarisation in future events. Our studies demonstrate how the detection of polarisation will constrain crucial parameters of these systems, such as the inclination and composition, distribution and extent of the different components of the ejecta.

Astronomical News
Meakins, S., Gómez, M. et al.
ESO Conference Proceedings 2.0 at Zenodo
ADS BibCode: 2018Msngr.174...38M
Meakins, S., Gómez, M., Bordelon, D., Grothkopf, U.
As of the past few years, ESO no longer publishes conference proceedings, mainly because of the large effort involved in their production and the relatively small impact of proceedings papers. In order to continue to preserve a record of ESO-hosted conferences, the ESO Library has implemented a system called "Conference Proceedings 2.0". Presentation slides and posters are made available through Zenodo, a CERN-developed platform for the permanent storage of digital research output, ensuring that content is citable, discoverable, and archived.

Smiljanic, R., Hussain, G. et al.
Report on the ESO Workshop "A Revolution in Stellar Physics with Gaia and Large Surveys"
ADS BibCode: 2018Msngr.174...40S
Smiljanic, R., Hussain, G., Pasquini, L.
The exquisite astrometry and photometry of ESA’s Gaia satellite combined with data from other large photometric, spectroscopic, and asteroseismic stellar surveys are enabling a revolution in our understanding of stellar physics. The goal of this workshop was to bring together a diverse community working on or making use of various aspects of stellar physics. The discussions covered both recent advances in the field and expectations for when new data and surveys become available.

Manara, C., Schneider, P. et al.
Report on the ESO Workshop "Take a Closer Look: The Innermost Region of Protoplanetary Discs and its Connection to the Origin of Planets"
ADS BibCode: 2018Msngr.174...44M
Manara, C., Schneider, P., Hussain, G., Facchini, S., Miotello, A.
About 150 scientists from all over the world convened at the ESO Headquarters to discuss the origin of close-in exoplanets and the properties of the inner regions of protoplanetary discs, where these planets are formed. In a cordial atmosphere, made possible by the collaborative attitude of the very diverse group of attendees, the discussion led to a deeper appreciation of the importance of several observing techniques and of advances in modelling to tackle key open questions. In addition, the participants had the chance to experience a special show at the ESO Supernova Planetarium & Visitor Centre, which highlighted the potential of this facility.

Chen, C., Gallenne, A. et al.
Fellows at ESO
ADS BibCode: 2018Msngr.174...48E
Chen, C., Gallenne, A., Wylezalek, D.

Barcons, X., Spyromilio, J.
Riccardo Giacconi (1931–2018)
ADS BibCode: 2018Msngr.174...53B
Barcons, X., Spyromilio, J.

Personnel Movements
ADS BibCode: 2018Msngr.174...55E