ESO Science Newsletter May 2023
17 May 2023

This newsletter is a summary of recent ESO Science Announcement items. Follow the links or visit ESO Science Announcements to read more.

Science Announcements

MOONS Detector Systems – All Science Grade Detector Systems are Shipped

15 May 2023:

All six of the final Science Grade Detector systems have now been shipped to the UK Astronomy Technology Centre to be integrated into the MOONS instrument. The MOONS Detector System work package began in 2017 with the initial design phase and procurement. A total of eleven detectors have been tested in this time, this included 7 x Teledyne H4RG-15 detectors in the latest FRSBE package with 2.5 µm cut-off material (1 x Multiplexer, 1 x Engineering Grade, 5 x Science Grade detectors) as well as 4 x LBNL fully-depleted CCDs (2 x Engineering Grades and 2 x Science Grades). At the same time, 3 new test facilities had to be designed and developed, CRISLER for H4RG detector testing, CEAT for MOONS detector cryogenic cable testing and a new test cryostat for the CCDs.

Read more

The Messenger 190 is Now Available Online-only, Subscribe to Receive it into your Inbox

15 May 2023:

As previously announced, after nearly half a century in publication, ESO’s journal for science and technology, The Messenger, is making a jump into the digital world by becoming an online-only publication. As reader habits have continued to shift online along with journal publication practices, and with sustainability an ever greater focus at ESO, The Messenger has evolved accordingly. Readers will now be able to find both new and old issues of the historic journal at a new redesigned webpage, making the published articles in The Messenger more accessible, usable and traceable than before. 

Read more

Scientific and Technical Committee Meeting

15 May 2023:

Under its remit to “Advise Council and the Director General on policy matters of scientific and technical importance related to the planning and operation of ESO”, the STC had its 102nd meeting on 17 and 18 April in Vitacura, Chile. The agenda included the updates on current and future ESO facilities. As always the STC was deeply impressed by the high level of activity at all of ESO’s observatories -ALMA, ELT and Paranal/La Silla.

Read more

VLT MAVIS Instrument Passes Preliminary Design Review

10 May 2023:

MAVIS (MCAO-Assisted Visible Imager and Spectrograph) successfully passed its preliminary design review at the end of March. MAVIS is intended to be installed at the Nasmyth A focus of the VLT UT4 in 2030 (replacing Hawk-I/GRAAL), and is made of two main parts: an Adaptive Optics (AO) system that cancels the image blurring induced by atmospheric turbulence, and its post focal instrumentation, an imager and an IFU spectrograph, both covering the visible part of the light spectrum.

Read more

ALMA at 10 Years: Past, Present and Future

08 May 2023:

The ALMA partnership is organizing a conference to commemorate its first decade of science operations. The conference will take a look back at the observatory accomplishments, highlight its latest results and look forward to future technical developments. It will take place from 4 to 8 December 2023 in Puerto Varas, Chile. Abstract submission and registration for the conference is now open at the conference webpage with a deadline for abstract submission on the 31st of May 2023. 

Read more

Fifth Release of UltraVISTA Public Survey Data

05 May 2023:

UltraVISTA is an ultra-deep near-infrared survey of the central region of the COSMOS field. The fifth UltraVISTA data release comprises stacked images in YJHKs and NB118 narrow-band filters, as well as single-band and dual-mode source lists. The data release also contains a five-band merged catalogue, created from the individual Ks-selected source lists. The release is based on the observations carried out from December 2009 to mid 2019, corresponding to 81125 individual images. This is three years more than DR4. The additional data have almost homogenised the exposure time in the “deep” and “ultra-deep” stripes in the J, H and Ks filters, which now reach the same depths to ∼0.15 mag.

Read more

“Two in a Million” - The Interplay between Binaries and Star Clusters: Second Announcement

04 May 2023:

The conference “Two in a million” - The interplay between binaries and star clusters will be held at ESO Garching, Germany, between 11-15 September 2023. Both in-person and online participation will be possible. Please note that the list of invited speakers has been updated.

Read more

A Decade of ESO Wide-field Imaging Surveys - Second Announcement

02 May 2023:

The deadline for submission of abstracts has been postponed to Monday, 1st June 2023 and the organisers are welcoming contributed talks from researchers who have used ESO imaging survey datasets, but also broader community working on imaging surveys that put the legacy of VIRCAM and OmegaCAM surveys in perspective. Furthermore, the current list of invited speakers as well as the registration fees for in-person participants are now available on the workshop’s website.

Read more

Data Release of the MUSE Hubble Ultra-Deep Field Surveys (AMUSED) Mosaic Cubes and Catalogue

13 Apr 2023:

The release of the MUSE Hubble Ultra-Deep Field survey (Programmes 094.A-0289(B), 095.A-0010(A), 096.A-0045(A), 096.A-0045(B) and 1101.A-0127, PI R. Bacon) includes the deepest spectroscopic survey ever performed. The MUSE mosaic data cubes, with their 3D content, amazing depth, wide spectral range, and excellent spatial and medium spectral resolution, are rich in information. The 3σ point-source flux limit of an unresolved emission line reaches 3.1×10-19 and 6.3×10-20 erg s-1 cm-2 at 10- and 141-hour depths, respectively. The redshifts of 2221 sources have securely been identified and measured. With the exception of eight stars, the collected sample consists of 25 nearby galaxies (z < 0.25), 677 [O ii] emitters (z = 0.25 - 1.5), 201 galaxies in the MUSE redshift desert range (z = 1.5 - 2.8) and 1308 Lyα emitters (z = 2.8 - 6.7). This represents an order of magnitude more than the collection of all spectroscopic redshifts obtained before MUSE in the Hubble ultra-deep field area (i.e., 2221 versus 292). At high redshift (z > 3), the difference is even more striking, with a factor of 65 increase (1308 versus 20).

Read more

Upcoming ESO or ESO-related workshops

Doppler shifts precision and accuracy are the traditional aspects of spectral fidelity, but there are many others, such as: how well are the spectra characterized for noise, scattered light, detector effects, instrumental profile? What are abundance realistic uncertainties? Is precision enough or is accuracy required? Which are the limits of precise and accurate spectroscopy and which exciting science will new performances enable? Which science require spectral fidelity and how can we enable it? What is its present status and future perspective? With the installation of HARPS at the 3.6m telescope in La Silla 20 years ago, ESO community has a central role in this research. HARPS has been transformational, paving the way to the new generations of planet hunters. The aim of the conference is to discuss all the above topics, with a view to the long heritage of HARPS, the first 5 years of operations of ESPRESSO, the new results from NIR spectrographs, and future spectrographs such as ANDES at the ELTs.

Registration deadline is 15 May (abstract submission), 15 July (in-person registration), 1 September (remote participation)


Galaxies transform throughout their lifetimes as a result of internal processes, interactions with other galaxies, their environments, and the cosmic web. The interplay of these processes alters the distribution of properties used to characterise the galaxy population. Understanding the impact and relative importance of the interplay of these processes is critical to galaxy evolution as whole.This conference will aim at connecting observations and simulations of galaxy transformations across cosmic time.

A substantial fraction of cosmic star formation happens in star clusters, and binary populations residing in extreme cluster environments are fundamentally different from those in galactic fields. Each binary in a star cluster will evolve through a multitude of interactions with other cluster members. A better understanding of this evolution is required to answer some of the most pressing questions in modern astrophysics, from the origin of black-hole mergers to the characterization of galaxies in the early Universe. Historically, star clusters have always been cornerstones for our knowledge of stellar evolution. With this workshop, we aim to continue this legacy by establishing them as cosmic probes for binary studies. The workshop intersects four main fields of modern astrophysics: star formation, stellar and binary evolution, star clusters and their dynamics, and gravitational wave astronomy. With this scientific overlap, the workshop wants to bring scientists of all of these fields together and facilitate the scientific exchange that will lead to new insights and scientific breakthroughs.

Registration deadline is 31 May (abstract submission), 11 August (in-person registration), 1 September (remote participation)


It is very well established that galactic systems form and evolve in connection with their environment. The stellar mass budget and the appearance in terms of morphology, colors, star formation activity, and gas fraction of local galaxies are strictly connected to the inhabited region of the cosmic web, and to the linked evolution of the dark matter halo they reside in.

The goal of the conference is to explore the intricate relationship between galaxy evolution and the environment by unveiling all the aspects of such a connection.

Registration deadline is 10 April (abstract submission), 31 May (in-person registration)


With the end of VIRCAM@VISTA operations (first light June 2008, decommissioned March 2023) and OmegaCam@VST becoming a hosted telescope (first light Oct 2011, now managed by INAF), a decade of targeted wide-field imaging at ESO is coming to an end. Both instruments were largely dedicated to public imaging surveys, which have amassed a total of nearly 60,000 hours of telescope time. To commemorate these milestones, ESO organizes a 5-day workshop that reviews the legacy left by these instruments and summarizes the variety of scientific impact that these imaging surveys have on a wide range of research topics in astronomy, both in galactic and extra-galactic science.

Registration deadline is 1 September