4MOST - 4-metre Multi-Object Spectroscopic Telescope
4-m Multi-Object Spectroscopic Telescope


4MOST Control Electronics delivered to Potsdam

The Project Manager, Joar Brynnel, is happy to report that on 13 – 14 July 2022 the two main cabinets with 4MOST control electronics were delivered and successfully installed in the AIP integration hall. In addition, the 4MOST Network and Workstation cabinet was installed in the computer room adjacent to the integration hall. All of these had previously been deployed at various 4MOST partner sites for subsystem operation.

This was a major effort coordinated by MPIA (Michael Lehmitz and Tobias Adler) with support from AIP (Deborah Sobiella, Allar Saviauk, Carlos Rodriguez, Thomas Hahn, Rainer Herbst, Michael Furch, Henrik Gieseking, Roland Winkler, and others). With these cabinets available at the AIP we are now able to control and operate all 4MOST subsystems using the final control system, which is an important step in preparation of the upcoming end-to-end system testing activities. Many thanks to all involved and we are looking forward to continuing the system integration and verification using the real control system!

Front view of the main cabinets.

Rear view of the main cabinets.

Network and workstation cabinet.

4MOST Wide Field Corrector installed on the Cassegrain Test Stand

The Project Manager, Joar Brynnel, reports:

The 4MOST Wide Field Corrector (WFC) is a large optical system to be mounted on the VISTA telescope in front of the fiber positioner to correct the telescope beam and to create a suitable focal plane. The six large lenses in the WFC, with a diameter of almost one meter, were manufactured by KiwiStar Optics in New Zealand. They were then sent to UCL in London where the optics were installed in their mechanical structure and optically aligned.

On 28 May 2022, the WFC was delivered to the AIP in Potsdam. As the 4MOST WFC is the most expensive subsystem built and delivered by the 4MOST consortium, it was a big relief to learn that the integrated WFC had survived the transport from London to Potsdam without any damage.

On 14 July 2022, the WFC was mounted for the first time on the Cassegrain Test Stand (CTS) in the AIP integration hall. As this was the first time the WFC was handled using its dedicated lifting tool, it was an exciting operation that required quite some preparation. We are very happy to report that the handling and installation went very smoothly and according to plan. Michael Schröck, the WFC work package manager reports: “The installation of the Wide Field Corrector on the Cassegrain Integration Stand was a long awaited handling maneuver to be performed at AIP, with many first time applications of handling tools and hardware combined in one procedure. Thanks to a committed team, careful preparation, and some amount of luck the whole effort went very smoothly. The WFC was successfully installed on the test stand in two hours, verifying the fit of individual components and planned tasks during the process.”

The installation of the WFC on the CTS is an important milestone for 4MOST system integration activities, and we can now continue to integrate the Acquisition & Guiding subsystem, Focal Surface Test Tools, and the Cassegrain Cable Wrap on the CTS, which, when completed, will mark the beginning of full system integration. Fingers crossed for continued success in the integration hall!

Time lapse video of moving the WFC from its trolley to the CTS using the overhead crane. In the video: Mark Cunningham (UCL), Carlos Rodriguez, Michael Schröck, and Allar Saviauk (AIP).

The WFC (black cylinder) during integration on the CTS (white structure) by Carlos Rodriguez, Michael Schröck, and Allar Saviauk (AIP). The orange device is the dedicated WFC lifting tool.

The WFC on the CTS as seen from the front of the WFC. The WFC optics are protected by the black circular cover.

Update on Local Acceptance Reviews

The Project Manager, Joar Brynnel, reports:

As the hardware of the 4MOST sub-systems is getting ready for delivery, the activity connected to the Local Acceptance Reviews (LARs) is ramping up. On 09 June 2022, the LAR for the Calibration System was held, followed by LAR part 1 for the High Resolution Spectrograph (HRS) on 10 June 2022.

The Calibration System hardware was brought from NOVA to LSW in Heidelberg on 07 June 2022 for final tests together with the HRS. After re-assembly of the Calibration System hardware, data was collected for performance verification. The formal LAR meeting was scheduled for 09 June 2022, and it was attended by NOVA (Johan Pragt, Ramon Navarro and Ioannis Politopoulos), ESO (Jeff Pirard), and the Project Office (Olga Bellido, Aida Ezzati-Amini, Steffen Frey, Domenico Giannone, Roelof de Jong, Genoveva Micheva and Joar Brynnel). The LAR meeting was graciously hosted by LSW. We were able to go through the complete set of LAR tests and checks, and an action item list was agreed on. As the Calibration System hardware still needs some work, it was decided to ship it back to NOVA after the LAR. A follow-up meeting has been scheduled for 8 – 10 August 2022 to close out the open action items. The Calibration System is expected to be shipped to the AIP for 4MOST system integration and testing on 11 – 12 August 2022.

Regarding the HRS, it was decided to split its LAR into two parts: the first part comprised the review of the compliance matrix to verify the optical performance of the HRS instrument. This part was held on 10 June 2022, and it was concluded that the performance of HRS is excellent with no major problems identified. The decision to split the HRS LAR in two parts was driven by the need to transfer the HRS control electronics to the AIP as soon as possible, at which point no more HRS data can be taken at LSW. As the documentation package is not yet complete, this will be reviewed during LAR part 2 in early August together with all other formal aspects of the WP. Shipment of the HRS to the AIP is scheduled for 22 August 2022.

The two main cabinets of the Calibration System at the time of LAR. To the left is the electronics cabinet, and to the right the optics cabinet.

The High Resolution Spectrograph during LAR inspection. The black panels are part of the thermally insulated spectrograph cover. One panel has been removed for inspection of one of the CCDs. The aluminum scaffolding surrounding the HRS is used to provide access to the slit unit through an access port on the top.

4MOST Science Team Meeting 2022

The 4MOST Science Team Meeting 2022 was held at Hamburg University and online on 23 – 25 May 2022. This was the first STM to include the members of the recently selected Community Surveys and it represented the endpoint of the community onboarding programme, thus completing the integration of the Community Surveys into the 4MOST Science Team. With 168 registered participants, of which ~80 were present in Hamburg, the programme mainly revolved around discussions within and among the various Surveys and Infrastructure Working Groups. Reassuringly, after two years of pandemic and with many new colleagues having joined the team, the collaborative spirit of the 4MOST Science Team was found to be as healthy as ever.

Introducing the new Ombudspersons

The 4MOST Project is pleased to announced that two Ombudspersons are now available for all 4MOST members. The role of the Ombudspersons is to provide informal, confidential, nonjudgmental, impartial, and independent advice, and to arrange mediation for 4MOST members for the purpose of dispute resolution (see the full guidelines). The two Ombudspersons are Chiara Battistini of Heidelberg University and Alastair Edge of Durham University. The search for a third Ombudsperson will be launched soon.

Chiara Battistini

Chiara studies the evolution of element abundances in the Milky Way. She was a PhD student representative on the departmental board at Lund Observatory and is currently a postdoc representative at the Zentrum für Astronomie (ZAH) in Heidelberg. She has been involved in 4MOST since 2015 and is an active member of the Milky Way Halo High Resolution Survey and several working groups (IWG1, IWG2 and IWG7). She is also the science representative of ZAH in the 4MOST STSC.

What motivated Chiara to become a 4MOST Ombudsperson? “Having been involved in 4MOST for several years gives me a good perspective on the full project, all its ramifications and the potential issues that might appear. At the same time, being an early career scientist and not involved in any high level position inside 4MOST makes me easily approachable in case of issues, especially from peers. I also think that during these years I showed dedication and availability, so also for more senior scientists I should be easily reachable and they would feel that I can take care of the issues they might have in a concrete way.”

Alastair Edge

Alastair works on galaxy clusters and AGN using radio, X-ray and optical observations and is a member of the Galaxy Clusters Survey. He has been the departmental Equality and Diversity lead, sat on a number of university wide committees, and is co-Chair of the LSST:UK Board.

Regarding his motivation to become a 4MOST Ombudsperson he says: “I have extensive experience of large international collaborations over the last three decades. These projects range from the ROSAT All-Sky Survey to SKA precursor radio surveys. I am familiar with the breadth and diversity of the 4MOST science projects and the groups leading them. From experience, I am aware of the importance of a strong collaborative culture within projects and will strive to uphold and promote that throughout the 4MOST community. This role may be viewed as more of a “referee” but I hope that I can be as much a “coach” ensuring that the early career researchers that are so vital to the success of 4MOST are given the space to thrive.”

LRS-A arrives in Potsdam

4MOST is built around three spectrographs that will collect the spectra of up to 2436 astronomical objects simultaneously. Two of these are identical low-resolution spectrographs (LRS), one is a high-resolution spectrograph (HRS), each fed by 812 fibres. Each spectrograph has a blue, green and red arm, in fixed configuration, and each arm is equipped with a 6k × 6k CCD detector. The two LRS provide continuous wavelength coverage from 390 to 950 nm at a resolution of R > 4000. Once completed, all three spectrographs will be sent to the AIP for system testing and validation.

In December 2021, integration of the first of the three spectrographs (LRS-A) was completed at the 4MOST consortium institute CRAL in Lyon. After acceptance testing, it was disassembled and packed in preparation of shipment to the AIP. On 29 March 2022 the disassembled LRS-A arrived at the AIP on four trucks. A team of five colleagues from CRAL, supported by the 4MOST AIP integration team and two colleagues from MPIA Heidelberg will spend the better part of the three following weeks to unpack and reassemble the spectrograph.

The delivery of LRS-A is a major milestone for the 4MOST project and we are very excited to receive it and follow its re-integration in the integration hall. The two remaining spectrographs are scheduled for delivery to the AIP in August and October of 2022.

See also this AIP press release.

Members of the teams from AIP and CRAL next to the LRS-A thermal cover in front of the AIP integration hall airlock. From left to right: Florence Laurent (CRAL), Jean-Emmanuel Migniau (CRAL), Roelof de Jong (AIP), Steffen Frey (AIP), Deborah Sobiella (AIP), Pasko Roje (AIP).

Community Surveys selected

During the first five years of 4MOST operations, 30% of the available observing time will be used for conducting a set of surveys initiated by the ESO community. The twostep selection process for these surveys, which began in 2019, has now been completed: ESO has announced the selection of 15 Community Surveys, covering a wide range of Galactic and extragalactic science cases. These will now join the existing 10 Consortium Surveys to form the final 4MOST survey programme. The completion of its survey programme is a major milestone for the 4MOST project, and the 4MOST consortium would like to extend a very warm welcome to the Community Survey teams. “We are very glad to have these Surveys on board as they will significantly enhance the scientific scope of the 4MOST survey programme. We are looking forward to a close collaboration in exploiting the many exciting scientific opportunities that lie ahead,” said Roelof de Jong, the 4MOST Principal Investigator.

The next step is to integrate the Community Surveys into the existing 4MOST Science Team, and to familiarize the new members with the complexities of 4MOST operations and the management of the project. To this end, the consortium has prepared an extensive “onboarding” programme, consisting of eight online training sessions and culminating in the Science Team meeting in May 2022. The first three of the online sessions will be held twice in order to accommodate participants from all time zones. They will also be recorded and the recordings will be made available here afterwards. The connection details will be distributed by email. The training sessions are open to all members of the Community Surveys as well as to all existing 4MOST members. The current programme for the online training sessions is listed below. Please note that this may still evolve, so please check back frequently.

Session 1
  • Programme Introduction & Project Culture (R. de Jong, 4MOST Principal Investigator)
  • Overall Organisation of 4MOST (J. Brynnel, 4MOST Project Manager)
  • Breakouts
  • Philosophy of 4MOST – sharing the focal plane (K. Lind and J. Loveday, 4MOST Project Scientists)
  • Signing up on 4most.eu (J. Liske)
  • Meet the Principal Investigator, Project Manager and Operations Manager
2022-02-10 15:30 – 17:30 CET
2022-02-11 09:30 – 11:30 CET
Session 2
  • Introducing the Science Team and the Science Coordination Board (E. Starkenburg, Deputy SCB Chair)
  • Science Team Policies (J. Liske, SCB Chair)
  • Breakouts
  • Introduction to 4MOST operations and data-flow (J. Walcher, Operations Manager)
  • Meet the SCB chairs and Project Scientists
  • Hands-on session for relevant persons only:
    • Membership management (J. Liske)
2022-02-23 09:30 – 11:30 CET
2022-02-23 15:30 – 17:30 CET
Session 3
  • Introducing the Helpdesk (J. Knoche, Helpdesk manager)
  • Simulating our survey – the work of IWG2 (P. Norberg and J. Storm, IWG2 leaders)
  • Breakouts
  • Verifying and documenting your catalogue – the work of IWG1 (D. Alexander and N. Kacharov, IWG1 leaders)
  • Meet the IWG1, IWG2 and Helpdesk leaders
  • For relevant persons only:
    • Tools in IWG1 (N. Kacharov, IWG1 co-leader)
    • Introduction to navigating the IWG2 outputs (J. Storm, IWG2 co-leader)
2022-03-10 15:30 – 17:30 CET
2022-03-11 09:30 – 11:30 CET
Session 4
  • Overview of 4MOST pipelines, data levels & formats, and Operational Rehearsals (C. Worley, Operations System Engineer)
  • Introduction to the Science Policy Board (K. Maguire, SPB chair)
  • Meet the SPB chairs, Operations System Engineers and Instrument Scientist
2022-03-23 09:30 – 11:30 CET
Session 5
  • Survey Management Plan (Karin Lind, Galactic Project Scientist)
  • Data Releases (Jon Loveday, extragalactic Project Scientist)
  • Galactic Analysis Pipeline – the work of IWG7 (R. Church and G. Kordopatis, IWG7 leaders)
  • Break
  • A guided tour of equipment in the AIP integration hall
  • Selection functions – the work of IWG4 (S. Sharma, E. Tempel and S. Martell, IWG4 leaders)
  • Meet the IWG4 and IWG7 leaders
  • For PIs only:
    • Discussion: create a Messenger issue describing all Community Surveys?
    • Document management with DocuShare (D. Johl, Consortium Manager)
    • Exercise: upload your ESO proposal according to DMP standards (R. de Jong)
2022-04-08 09:30 – 11:30 CEST
Session 6
  • Expected instrument performance and verification (O. Bellido and S. Frey, Hardware System Engineers)
  • Trade-offs when sharing the focal plane (P. Norberg and J. Storm, IWG2 leaders)
  • Breakouts
  • Extragalactic Analysis Pipeline – the work of IWG8 (J.-K. Krogager, IWG8 co-leader)
  • Meet the Hardware System Engineers, IWG2 and IWG8 leaders
  • For PIs only:
    • How do surveys contribute to the common infrastructure? (J. Walcher, Operations Manager)
    • I have resources, where can I deploy them?
    • Labour contributions accounting (R. de Jong, Principal Investigator)
2022-04-22 09:30 – 11:30 CEST
Session 7
  • Classification pipeline – the work of IWG9 (C. Heneka, IWG9 leader)
  • Commissioning and calibration plans (G. Micheva, Instrument Scientist) (M. Irwin, Data Management System)
  • Break: video of VISTA
  • Operations Startup Phase (J. Walcher, Operations Manager)
  • Meet the IWG9 leader, Consortium Manager and Project Controller
2022-05-04 15:30 – 17:30 CEST
Session 8
  • Data quality control (I. Pelisoli, Quality Control Scientist)
  • Software requirements (O. Streicher, Software Product Assurance Manager)
  • Data publication and archiving: the 4MOST Public Archive (4PA) (J. Knoche)
  • Meet the Quality Control Scientist, Software and Hardware Product Assurance Managers
  • For relevant persons only:
    • Hands-on session exploring IWG2 output (P. Norberg, IWG2 co-leader)
2022-05-20 09:30 – 11:30 CEST

SPIE 2022

After COVID-related cancellations of previous SPIE meetings in Japan and San Diego, we are now hoping for a physical SPIE meeting in Montreal during the summer of 2022. 4MOST will of course be strongly represented, with the following abstracts having been submitted:

  1. 4MOST – the 4-metre multi-object spectroscopic telescope project in the assembly, integration and test phase (R. de Jong et al.)
  2. 4MOST – MAIT of the High-Resolution-Spectrograph (W. Seifert et al.)
  3. 4MOST – manufacture, assembly and test of the optical fiber system (A. Kelz et al.)
  4. 4MOST Calibration System: Design, Assembly and Testing (J. Pragt et al.)
  5. 4MOST Guiding and Wavefront Sensing cameras – Requirements and early testing (O. Bellido-Tirado et al.)
  6. 4MOST Low Resolution Spectrograph Alignment (F. Laurent et al.)
  7. 4MOST Low Resolution Spectrograph Performances (K. Disseau et al.)
  8. 4MOST WFC_ADC (M.Cunningham, D. Brooks, P. Doel et al.)
  9. The 4MOST Calibration Plan (G. Micheva et al.)
  10. Overall performance of AESOP, the 4MOST fibre positioner (J. Brzeski et al.)
  11. AESOP, the 4MOST fibre positioner – Engineering Principle (J. Brzeski et al.)
  12. The 4MOST facility control software on its way to a fully fledged subsystem (F. Rothmaier et al.)

LRS-A Local Acceptance Review

A team from the 4MOST Project Office visited CRAL on 15 – 16 December 2021 to conduct the Local Acceptance Review (LAR) for the first Low-Resolution Spectrograph (LRS-A). The purpose of the LAR is to assess whether a subsystem is mature and complete before shipping it to the AIP for integration. During the weeks prior to the physical meeting, the deliverable documentation was submitted and reviewed, resulting in a set of comments and questions. At the two-day LAR meeting in Lyon the technical performance and cost were reviewed, the hardware was inspected, the instrument was operated using engineering GUIs, and more. 4MOST project members from MPIA and ESO also participated remotely.

In general, the performance of LRS-A was found to be excellent and no major issues were identified. Issues related to documentation and product assurance are well advanced and on par with expectations at this stage of the project. A list of Action Items has been produced as a result of the LAR. The plan is now for LRS-A to be shipped to Potsdam sometime in Q1 of 2022, with the exact date depending on other system integration activities.

The Project Office wishes to thank the LRS team at CRAL for their dedicated and competent work and superb collaboration. We are already now looking forward to coming back to Lyon when LRS-B is finished!


The CRAL and Project Office teams in front of LRS-A in the clean-room. The spectrograph is visible behind the blue airlock. From left to right: Jean-Emmanuel Migniau, Florence Laurent, Karen Disseau, Joar Brynnel, Olga Bellido, Domenico Giannone, Didier Boudon, Aida Ezzati-Amini, Aurelien Jarno, Alban Remillieux, Diana Johl. Other LRS team members not in the picture: Diane Chapuis, Eric Daguisé, Alexandre Jeanneau, Arlette Pécontal, Emmanuel Pécontal, Johan Richard.

4MOST Code of Conduct released

The 4MOST Code of Conduct (CoC) has recently been approved by the Science Coordination Board, the Executive Board and the ESO Director for Science, and it is now applicable to the work of all 4MOST Project members, including all Consortium Survey members. The CoC establishes important principles like open, respectful communication and a shared commitment to a set of values that include ethical conduct, civility, inclusiveness, and diversity. It also describes escalation procedures in case of conflicts. All 4MOST members will be required to confirm, once a year, that they have read the CoC and that they will adhere to it. The request to confirm the CoC (as well as basic contact details) will be launched soon by the 4MOST User Management System.

The CoC foresees the installment of at least two Ombudspersons, who will provide independent, confidential and neutral advice to members of 4MOST in case of problems or conflicts within the Project. They will also provide current information about services, programs, policies, and procedures. They will try to resolve problems through mediation or by making recommendations to the 4MOST leadership. Nominations for 4MOST Ombudsperson candidates have been solicited by the 4MOST Principal Investigator, Roelof de Jong, on 17 November 2021.