President’s Message

Dear CASCA Community,

I am closing out the final months of my term as CASCA president in a time of significant upheaval.  In light of recent and dramatic political changes, the expectations of long-standing partnerships are shifting.  We will have significant turnover in the CASCA Board in June, and the current members aim to finish specific community recommendations from the 2020 Long Range Plan before the transition.  Adopting a Mission and Values statement is foundational to this end, and the final consultation on the wording is open now.  Subsequently, we will have another round of consultation on a proposed Code of Conduct.  These documents are important for defining who we are and aspire to be, and how we treat each other.

The Mid-Term Review Committee has been working hard to gather information and engage our community.  The participation in the Town Halls to date has been robust and productive.  We will have further opportunity for discussion (in-person and virtual) at the CASCA AGM in Halifax in June.  Thank you to the Committee and all of you who have contributed to date in the consultations.  We are cognizant that the landscape in March 2025 is remarkably different than when papers and reports were submitted at the end of 2024.  We are in the process of figuring out how to incorporate new realities without being too reactive.  I ask for your patience as we work to navigate this challenge.

CASCA is only as effective as its leadership and the contributions of its members.  Suggestions of potential candidates (including yourself!) for the open Board positions (VP, Treasurer, Secretary, and Directors) continue to be most welcome.

Best wishes,
Sarah Gallagher

casca-president@casca.ca

CCAT Update

By/par Mike Fich (Waterloo Centre for Astrophysics) and the Canadian CCAT team

The CCAT team is pleased to announce that another major milestone has been reached in this project: the Fred Young Submillimeter Telescope (FYST) has arrived in Chile and assembly on the CCAT Observatory site will begin within the next few weeks.  Telescope commissioning will follow in August 2025.  First light instruments (a broad-band camera and a heterodyne spectrometer) will be installed in February 2026.

The Sloman Discoverer carrying the CCAT telescope through the Miraflores Locks of the Panama Canal

FYST is a 6-meter diameter submillimeter survey telescope and will be located at the best submillimetre site that has been identified anywhere in the world.  The CCAT partnership is led by Cornell University with German, Canadian, and Chilean partners. The Canadian participation is channelled through the Canadian Atacama Telescope Consortium (CATC) and includes researchers at ten Canadian universities.  The central camera module for FYST – a 350-micron 50,000-pixel device – is under development by a multi-institutional team led by Scott Chapman at UBC and scheduled for installation in 2027.  This camera will be the crowning jewel of FYST Planning is now underway for the Canadian provision of a second-generation camera to follow in a few years.  Much more detail on the project is available at the website www.ccatobservatory.org.

The CCAT team has been actively planning the science activities for FYST for several years and the plans are now in a quite mature state.  All of the observing time with FYST will be used in large surveys that are now well-defined.  Eight Key Projects have been identified.  Four of these Key Projects have Canadian leadership.  The sixth (annual) CCAT Consortium Meeting (CCM6) will be held in the Fall at Cornell (CCM5 was held at the University of Toronto).

The CCAT team is very much open to new members. We are especially encouraging new science ideas that we can explore with the amazing survey datasets we will create with FYST. If you have an interest in participating in the technology development or in any of the Key Projects please contact the author of this note, or Norm Murray (a CCAT Director), or a Key Project leader (listed on the website above).

Nouvelles de l’Office Gemini Canadien

Par Eric Steinbring (Office Gemini Canadien, Conseil national de Recherches Herzberg en Astronomie & Astrophysique)

Appel de Demandes

Un nouveau printemps (dans l’hémisphère nord) apporte trois occasions pour les Canadiens de demander du temps :

Bien que ce ne soit pas le cas pour Gemini-Sud, on observe une tendance quelque peu inquiétante à la diminution des demandes canadiennes pour le temps de la bande 1+2 (statistiquement, l’obtention des 60 % de conditions les plus favorables) dans le Nord, ce qui peut s’expliquer par plusieurs raisons, telles que la concurrence entre les instruments et les opportunités. Pour référence, la figure 1 est un graphique de la sursouscription du temps canadien disponible dans le Nord (bleu) et dans le Sud (rouge) au cours des dernières années. Rappelez-vous également qu’il est judicieux d’imaginer si des conditions détendues de la bande 3 (c’est-à-dire les 80 % de temps utilisables) peuvent contribuer à la réalisation de vos travaux scientifiques, même si cela signifie qu’il faut demander plus de temps pour mener à bien le travail. Il y a une section spéciale de la demande pour décrire exactement cette stratégie pour considération par le CanTAC. Si, au lieu de cela, des conditions de bande 4 (pour lesquelles il suffit que le dôme soit ouvert!) conviennent, vous pouvez toujours essayer une demande de conditions météorologiques défavorables.

Figure 1: Ce graphique montre la sursouscription du temps canadien en Bandes 1+2 pour les semestres réguliers au Nord (bleu) et au Sud (rouge) au cours des dernières années.

Dans le même ordre d’idées, le nombre de demandes canadiennes pour le programme FT, y compris pour des instruments dans le Nord, a augmenté récemment. Il convient de rappeler que le FT est un système de demandes distinct (rapide) qui ne passe pas par le CanTAC et qui mobilise 10 % du temps de Gemimi au Canada. Le programme FT peut s’avérer très utile lorsqu’une demande ne nécessite qu’un temps relativement modeste et qu’il est préférable de ne pas attendre l’appel de demandes régulier du semestre. N’oubliez pas que le temps discrétionnaire du directeur est toujours disponible (actuellement jusqu’à 5% par télescope) pour les demandes qui ne peuvent pas attendre et qui sont suffisamment importantes sur le plan scientifique pour le justifier. Enfin, il convient de mentionner deux nouveaux instruments sur Subaru qui peuvent être demandés via le temps d’échange : AO3k (le nouveau miroir déformable à optique adaptative) et PFS (Prime Focus Spectrograph). Bonne chance pour toutes vos demandes.

Enquête sur la Planification Stratégique

Plus loin à l’horizon, nous voudrions imaginer à quoi Gemini devrait ressembler dans les années 2030. Gemini est actuellement en train de formuler un nouveau plan de vision stratégique, guidé par les besoins de la communauté des utilisateurs.trices, ainsi que de tous les partenaires et parties prenantes de la communauté. Quelles sont vos priorités scientifiques pour Gemini, et comment les opérations de l’observatoire devraient-elles être modifiées (le cas échéant) pour mieux les atteindre? Quelles sont les nouvelles capacités qui, selon vous, devraient être mises en place pour atteindre ces objectifs? Nous vous invitons à nous faire part de vos réflexions sur ce plan à long terme pour la prochaine décennie. Pour en savoir plus, consultez le site https://www.gemini.edu/about/gemini-strategic-planning et répondez à l’enquête sur le site https://docs.google.com/forms/d/e/1FAIpQLScEkv2fiXwPZYXD05zBIo3eMhVF8jPwgHDWWYRdouKxSakxIg/viewform L’enquête est ouverte jusqu’au 12 juin 2025. Assurez-vous que votre voix soit entendue!

Nouvelles et mises à jour du TCFH

par Nadine Manset (Directrice des opérations scientifiques, au nom de la ʻohana TCFH)

Récemment

Lors de sa réunion de décembre 2024, le conseil d’administration du TCFH a fait une recommandation importante concernant le Maunakea Spectroscopic Explorer. Voir la mise à jour de Pat Hall dans ce bulletin.

Dans l’actualité scientifique, les astronomes de l’Université d’Hawaï ont joué un rôle central dans le suivi d’un astéroïde dont on craignait qu’il ne présente un risque pour la Terre. L’astéroïde 2024 YR4 a été découvert fin décembre et observé avec MegaCam dès sa première nuit au télescope en février. Avant les observations du TCFH, l’astéroïde avait une probabilité de 3 % d’entrer en collision avec la Terre en décembre 2032. Grâce aux données de MegaCam et aux observations d’autres observatoires, la probabilité est tombée à seulement 0,28 % et est désormais de 0,001 %. https://www.hawaii.edu/news/2025/02/20/hawaii-astronomers-asteroid-impact-probability-decreases/

MegaCam et son grand champ ont également permis une autre découverte majeure au sein de notre système solaire, cette fois grâce aux travaux d’astronomes canadiens. En mars, une équipe de l’Université de la Colombie-Britannique, dont fait partie Brett Gladman, a annoncé que Saturne compte désormais 128 lunes supplémentaires. Des observations répétées du ciel autour de Saturne entre 2019 et 2021 ont révélé l’existence de ces nouveaux satellites irréguliers. https://phas.ubc.ca/node/11828

Bientôt

La 14e Rencontre des utilisateurs du TCFH aura lieu du 26 au 28 mai au Lac-à-L’Eau-Claire, au Québec. Bien que la date limite de soumission des résumés soit passée, les inscriptions sont encore possibles,  jusqu’au 1er avril. Nous approchons du nombre maximum de participants pouvant être accueillis sur place, alors inscrivez-vous rapidement pour réserver votre place si vous souhaitez nous rejoindre en personne! La participation à distance est également possible. Le Comité de l’organisation scientifique travaille actuellement sur le programme, qui comprendra 2 ou 3 sessions pour préparer le Community Survey. La première session présentera, lundi, la portée, le contexte et le processus du CS. Les séances des jours suivants permettront des échanges entre les participants. https://www.cfht.hawaii.edu/en/news/UM2025/2ndannouncement.php

Maunakea Spectroscopic Explorer (MSE) – Last Update for Now

By Pat Hall (York University), MSE Management Group member

In December 2024, the CFHT Board of Directors made the following recommendation: 

The Maunakea Spectroscopic Explorer remains an exciting and competitive concept. The Board appreciates the efforts of all those who have worked over the years to help define MSE’s technical and scientific readiness. MSE’s timeline is, however, strongly delayed, and at the present time the Observatory’s priority must be to ensure it continues to operate as a scientifically effective facility into the 2030s. For this reason, The Board does not approve any additional allocation of internal funds towards MSE activities, beyond those absolutely necessary to responsibly and safely bring current activities to a stop. The ultimate realization of MSE in some form currently remains the best plan for the long term future of CFHT. The Observatory, through consultation with the SAC and the User community may, however, explore alternatives to MSE that achieve compelling science that utilizes the unique site on Mauna Kea. The Board remains committed to achieving a scientifically productive future for CFHT beyond 2033, building on its long tradition of excellence and the outstanding work of the CFHT staff.

Following this recommendation, CFHT is winding down all MSE activities. The Board acknowledges that MSE in some form remains the current best plan for the CFHT site under the new astronomy lease at Maunakea. Support from the current and future CFHT community will be essential to determine what future capabilities the CFHT will have. 

The near-term future of CFHT will include Community Surveys and (https://www.cfht.hawaii.edu/en/science/CommunitySurvey/) starting in 2027 at the earliest, possibilities for which will be discussed in detail at the next CFHT Users’ Meeting, May 26-28, in Quebec. (https://www.cfht.hawaii.edu/en/news/UM2025/). In response to the board’s recommendation on alternative instrumentation to MSE, interpreted as potential upgrades to CFHT prior to MSE’s implementation, the community was invited to present ideas and will discuss technological upgrades and alternatives at the upcoming CFHT Users Meeting’s instrumentation session.

The science case for wide-field 8-meter-class spectroscopy in general, and MSE in particular, remains compelling. Meanwhile, such spectroscopy is becoming a reality with PFS on Subaru, and work toward proposed dedicated facilities continues in the form of the ESO WST project (https://arxiv.org/abs/2405.12518) and the Spectroscopic Stage-5 Experiment (https://arxiv.org/abs/2503.07923). Partnership with those initiatives might be a way to involve CFHT in a future dedicated 8-meter class spectroscopic facility, if supported by the CFHT community.

Speaking personally as someone who has been an advocate for MSE since 2013, I know that the MSE scientific community worldwide made great efforts to secure funding to start this project sooner rather than later. I thank everyone in Canada and elsewhere who has worked on them to date.  

ngVLA Update

By Erik Rosolowsky (University of Alberta), Joan Wrobel (NRAO)

Prototype Antenna Dish Lift

The construction of the ngVLA prototype antenna was streamed live from New Mexico, USA on February 6. Viewers worldwide watched as the 18m dish was successfully lifted onto its pedestal. Missed the live stream?  Watch a replay! The image below shows the installed antenna. The prototype will be used for design characterization.

Prototype ngVLA dish successfully installed at the VLA site in New Mexico. Image credit: U.S. NSF / AUI / NSF NRAO

VLA+VLBA to ngVLA Transition Option Concepts

An external and international committee, the Transition Advisory Group (TAG), was asked to make recommendations regarding option concepts for a VLA/VLBA to ngVLA transition. On January 14 the TAG posted its draft report. The report recommends full VLBA operations and maintaining VLA operations as long as possible, including a maximal receiver suite and changing array configurations. If it is impossible to maintain the VLA up to the late stages of ngVLA construction, the TAG proposes a reduced receiver suite (L-C-S-X-K) as a first fallback and a fixed array configuration as a second fallback.

The TAG co-chairs announced the posting during Session 183 at the AAS 245 Winter meeting. Comments were sought from the 70+ session participants. The TAG is now collecting comments from the broader community until mid-April. Comments may be emailed to ngvla-transition-feedback@listmgr.nrao.edu. The TAG will consider all comments as it develops its final advisory report to NRAO, due later in the year.

CASTOR Update

By Patrick Côté (NRC-Herzberg), Tyrone Woods (University of Manitoba)

  • The Coalition for Canadian Astronomy. The Coalition for Canadian Astronomy — which brings together representatives from the astronomical community (CASCA), the Association of Canadian Universities for Research in Astronomy (ACURA) and industry — has the goal of securing federal funding for projects endorsed by the LRP. The Coalition is continuing its vigorous efforts in support of CASTOR, meeting with representatives from CSA, NRC, industry and the federal government on multiple occasions. The highest priority for the project remains the approval of a mission-defining Phase A study (and associated technology development) that would include formal agreements with international partners who await this critical next step.
  • Detector Testing and Characterization Program. Upgrades to the vacuum ultraviolet calibration facility at the University of Calgary are nearing completion. This specialized facility is being used in a long-term program to test and characterize delta-doped CMOS detectors for the CASTOR mission. QE-enhanced CIS120 CMOS detectors from Teledyne-e2v and JPL have now been delivered to the facility, along with custom readout electronics developed by NRC-HAA. This facility will also feature prominently in the three-year NRC Small Teams project that is building a proto-type UVMOS instrument, in collaboration with France (Marseille) and Colorado (LASP). Promising discussions are also underway with GOLD (Grupo de Óptica de Láminas Delgadas), a research group affiliated with Instituto de Óptica-CSIC (Madrid, Spain) that specializes in optical coatings for use at UV wavelengths.
  • CASTOR Overview Paper. The Journal of Astronomical Telescopes, Instruments and Systems (JATIS) will soon publish a special issue entitled « Ultraviolet Science and Instrumentation: On the Way to Habitable Worlds Observatory and Beyond”. An invited review of the CASTOR mission was recently accepted for publication in this special issue of JATIS, which will be available soon. This article provides an up-to-date summary of the current design, science plan, and ongoing technology development — with a focus on synergies with NASA’s upcoming Habitable Worlds Observatory. The large number of coauthors (180) reflects the many individuals who have contributed to the scientific, technical and programmatic development of the mission since 2010.
  • Science Planning Tools. Work continues on the development of various science planning tools for the mission, carried under the FORECASTOR initiative (Finding Optics Requirements and Exposure times for CASTOR). Recent highlights include the development of a survey scheduling and implementation tool (including a careful trade study on the choice of downlink technologies for the mission), Pyxel-based simulations of the in-orbit performance of CASTOR’s expected flight detectors, and the continuing development of a grism ETC and data simulator. A priority for the coming semester will be the extension of the survey scheduling tool to the case of non-sidereal targets within our solar system. A series of monthly FORECASTOR zoom meetings brings together astronomers and developers with shared interests in these tools. For more details, contact the one the mission science leads.
  • Town Hall at 2025 CASCA AGM. The upcoming CASCA AGM, to be held in Halifax on June 2-5, will feature an ACURA Town Hall. The first half of this lunchtime session will be devoted to SKA, and the second half to CASTOR. Community members are encouraged to attend to learn more about the current status of the mission and its ongoing development. The AGM will also feature a dedicated session on the MTR which is reviewing the state of our field, including progress towards realizing the LRP’s goals in space astronomy.

    For more information on the mission, see https://www.castormission.org

Cassiopeia Newsletter – Vernal Equinox / équinoxe du printemps 2025

spring

In this issue / Dans ce numéro:

President’s Message
ALMA Matters
CCAT Update
Update on CASTOR
CFHT News and Updates / Nouvelles et mises à jour du TCFH
Gemini News / Nouvelles de l’Office Gemini Canadien
Maunakea Spectroscopic Explorer (MSE) Update
ngVLA Update


Editor: Dennis Crabtree

Cassiopeia is CASCA’s quarterly Newsletter, published on or near the solstices and equinoxes (March 21, June 21, September 21 and December 21).

To submit a contribution please email cassiopeia.editors@gmail.com. All submissions must be received by the due date (usually 2 weeks in advance of publication) to be published in the next edition. I accept plain text and Word documents. Note that the formatting of your document will not be preserved. Please include any images as attachments in your email, not embedded in the text. Please include URLs in parentheses next to the word or phrase that you wish to act as link anchors.


ALMA Matters

By Brenda Matthews & Gerald Schieven (NRC-HAA)

Cycle 12 Call for Proposals Open (March 20)

The ALMA Director, on behalf of the Joint ALMA Observatory and the partner organizations in East Asia, Europe, and North America, is pleased to announce that the ALMA Cycle 12 Call for Proposals (https://almascience.org/proposing/call-for-proposals) for scientific observations is now OPEN!

ALMA Cycle 12 is currently scheduled for observations from October 2025 to September 2026. Users of any nationality or affiliation are invited to submit proposals before the deadline of 15:00 UT on Thursday 24 April 2025.

Full details about capabilities, applying, and other information can be found at https://almascience.nrao.edu/documents-and-tools.

Proposal Preparation Webinar and Workshops

Webinar  – Join the ALMA Ambassadors for a webinar on 02 April at 2pm Eastern, in preparation for the Cycle 12 proposal deadline (24 April 2025). This webinar will provide an overview of the basics of ALMA, new capabilities in Cycle 12, and proposal preparation (including dual-anonymous and distributed peer review). The webinar will be followed by a brief Q&A session. Please register at: https://nrao-edu.zoom.us/webinar/register/WN_M5as44qrR7qUoB851XrWAw

Workshops – The North American ALMA Science Center (NAASC) and the Cycle 12 ALMA Ambassadors have also organized a series of ALMA proposal preparation workshops, to take place between 21 March and 05 April 2025. The goal of these events is to provide users with the knowledge they need to carry out cutting-edge scientific research using ALMA. We are particularly interested in reaching new users, so no experience with radio astronomy is required to participate!

Registration for these workshops is free. The workshops are designed to assist you in proposal preparation and observation planning for ALMA Cycle 12, and may include talks on the following topics:

  • ALMA Basics and Cycle 12 Capabilities
  • Radio Interferometry Basics
  • Cycle 12 Proposal Preparation and the Proposal Review Process
  • Introduction to the ALMA Observing Tool
  • ALMA Data Products, Archive Use, and Notes on the Pipeline Weblog
  • Common Astronomy Software Applications (CASA) Simulations
  • Science-ready Data Products

Workshops are being held in person as well as virtually in two locations in Canada:

In-person and virtual workshops are also being held in locations across the United States, Puerto Rico, and Chile. For information and registration for all workshops, please go to https://science.nrao.edu/facilities/alma/community

These ALMA workshops and webinar are hosted by experienced postdocs and graduate students as part of the ALMA Ambassadors program, which is open to graduate students and postdocs at any institution in Canada or the United States. Check out https://science.nrao.edu/facilities/alma/ambassadors-program/ for more information and to learn about applying.

ALMA Primer Video Series – New Releases

The ALMA Primer Instructional Video series, which can be found on the Science Portal at https://almascience.nrao.edu/tools/alma-primer-videos, is designed to provide a basic introduction to radio interferometry, calibration, imaging, and other topics in short (5-10 minute), easy-to-digest segments. As a work in progress, new videos are released periodically.  Recent videos include a brief introduction to how ALMA’s heterodyne receivers work (https://youtu.be/rpbaPNwntb0?si=JHsWTQ1OIYDTxali), and a series explaining sidebands, basebands and spectral windows (https://youtu.be/bm6vrEWAlYM?si=R2NIYvcZ1vnXBRd-), with practical examples on tuning setups (https://youtu.be/1zWwLrsBwA4?si=elgmOu8SGFtpKQaJhttps://youtu.be/18qE2-u0rMY?si=We49svch4_AfKctC). A new video on Primary Beams and Field-of-View is under production and is expected to be released by April 2025.

Other videos in the series include an Introduction to Radio Interferometry, Calibration, CLEAN, and much more. Subscribe to the ALMA Primer Video Series YouTube channel (https://www.youtube.com/@almaprimer920) to be alerted to new videos as they are released.

We are always looking for ideas for new videos, and especially looking for people who would like to help with script generation, animation, and narration. If you have an idea or want to join the Primer Video Working Group (at any level of effort), please contact gerald.schieven[at]nrc-cnrc.gc.ca.

ngVLA update

By Erik Rosolowsky (University of Alberta), Joan Wrobel (NRAO)

In December a position paper on the Next Generation Very Large Array (ngVLA) was submitted
for the Mid-Term Review of LRP2020. A slightly modified version of the paper appears below
which we hope summarizes ngVLA developments over the past few years. If you want to get
more involved in ngVLA efforts in Canada, email rosolowsky [at] ualberta.ca

The ngVLA in a Nutshell

The ngVLA is a proposed new centimetre-wave interferometer that is being developed by the
US National Radio Astronomy Observatory (NRAO) to replace two existing aging facilities, the
Jansky Very Large Array (VLA) and the Very Long Baseline Array (VLBA). The ngVLA would
provide factors of 10 improvements in sensitivity and resolution relative to the VLA over the
critical frequency range of 1.2-116 GHz, positioning the new facility to become the premier world
observatory at frequencies between those covered by the Square Kilometre Array (SKA) and
the Atacama Large Millimeter/submillimeter Array (ALMA).

Conceptual design for the ngVLA. The ngVLA would comprise 244 antennas of 18-m diameter clustered in the US southwest but spread out between Hawaii and the US Virgin Islands, an 8860-km maximum baseline. Antenna placements in Canada and Mexico are under consideration. The ngVLA would also involve 19 antennas of 6-m diameter in a close-packed array at the current VLA site in New Mexico. Image credit: ophia Dagnello (NRAO/AUI/NSF)

The ngVLA would enable science not achievable with either ALMA or the SKA. For example, improved sensitivity at 30 GHz would  allow the measurement of the optically thin Rayleigh- Jeans tail of dust emission from protoplanetary disks, resolving planet formation across 1000s of systems. Interferometer sensitivity is driven in part by collecting area, and ALMA lacks the sensitivity to make these measurements, even with the ALMA 2030 upgrade. Furthermore, the SKA would not reach sufficiently high frequencies to detect dust emission.

Strategically, the ngVLA would provide unmatched capabilities to:

  • Observe planets in formation in the terrestrial zone of protoplanetary disks;
  • Observe prebiotic molecules and chiral molecules in hot cores;
  • Capture key organic and inorganic molecules like carbon-chain species, NH 3 , and radio
    recombination lines that trace the dust and gas chemistry and kinematics of star
    formation;
  • Probe the thermal radio continuum and long wavelength dust emission;
  • Access key spectral transitions like the fundamental transition of the CO gas tracer from
    z=0 to z=12;
  • Observe elusive pulsars toward the Galactic Centre to make precise tests of gravity;
  • Probe the formation and evolution of black holes in the era of multi-messenger astronomy; and
  • Observe targets in the northern hemisphere.

Key ngVLA Developments Since LRP2020

The ngVLA was evaluated in LRP2020 and presented as one of the Recommended Ground-Based future facilities for Canadian participation, with the caveat of its status in the US Decadal review. Astro2020 subsequently rated the ngVLA as one of the key new facilities for US ground-based astronomy, alongside an optical ELT and CMB-S4. Driven by the strong US Decadal support, NRAO has rapidly developed the ngVLA design, successfully passing a Design Review in September 2024 and preparing it for acceptance by the US National Science  Foundation (NSF). The project is now in the US NSF’s Major Research Equipment and Facilities Construction queue, which is essential for the project to proceed to the construction phase. A Preliminary Design Review is expected to occur in approximately 18 months.

The US NSF has provided sufficient funding support to design, build and test a prototype 18-m ngVLA antenna. This prototype is now being assembled at the current VLA site in New Mexico and is expected to be turned over to NRAO for testing in early 2025. With continued support and development, the ngVLA could begin early science in the start of the next decade with full capabilities available in the late 2030s. While the US expects to be the primary funding source for the ngVLA, the project is seeking international partners. Thus far, early ngVLA developments have engaged the technical communities in Canada, Mexico, Germany, and Japan, and science communities worldwide. The ngVLA construction phase has a total project cost of US$3.2B (FY2020) according to Astro2020 TRACE analysis. External partners (both international and US domestic partners) are expected to provide ~25%. The science interests in the Canadian community should support a similar level of engagement as for ALMA or the SKA at approximately 5%.

One primary strength of the ngVLA is its mature facility design, underpinned by NRAO’s many decades of experience in the construction and operation of the VLA, VLBA, and ALMA. Overall, the ngVLA is low-risk in terms of technical design and has flexibility regarding exactly where its antennas will be located.

In the broader landscape of long-wavelength Canadian observatories, Canada has joined the SKA, securing access to cutting-edge low-frequency radio astronomy. Canada also remains actively engaged in submillimetre observations through ALMA, which has a robust upgrade and development plan to improve capacity, especially at >100 GHz. However, the key global facility in the 10-50 GHz range remains the 45-year old VLA.

Without being an ngVLA partner, Canada would need to access the facility through the Open Skies program, for which the US NSF has an expectation of reciprocity. It is anticipated that all SKA partners not involved in ngVLA construction or operations may collectively be limited to <5% of ngVLA time. In contrast, an SKA partner who contributes to ngVLA construction and operations can expect to be able to participate in the larger pool of Open Skies time.

Why the ngVLA Must Remain a Top Canadian Priority

  • Participating in the ngVLA would provide an essential waveband to support Canadian science priorities as articulated in the LRP (galaxy evolution, star and planet formation, transients, pulsar astronomy, black hole growth). These opportunities would be unique to the ngVLA, with neither the SKA nor ALMA able to execute its key science goals.
  • Our existing national expertise in low-cost antenna production, receiver development and correlators for interferometers, primarily through NRC, means that we would have clear opportunities for contributions to the ngVLA. This includes both design work, as is currently happening, and in the construction of the facility. Continuing our legacy of excellent hardware contributions would further develop our national STEM capacity and would continue to have spin-off applications for Canadian industry.
  • Being a partner in the ngVLA would ensure a Canadian voice in its science steering and to lead major discoveries with the ngVLA. Key science projects are being designed now. Canadians are welcome at this point because of our expertise and potential engagement, but we risk being frozen out of defining the major science cases for this facility if we do not establish formal partnership. These science cases align well with LRP2020 goals and will remain active science themes throughout the next decade.
  • Investment in the ngVLA would happen primarily in the next decade, but Canada should be planning for this transformational instrument now. Given the robust design and low- risk for construction, we could present a clear case and timeline for funding that happens after our SKA construction contributions. Furthermore, the US has historically been a reliable partner in radio astronomy (e.g., in the upgrades to the VLA and in our partnership in ALMA). Additionally, the ngVLA would be administered through partnership agreements that do not require extensive governance development. Hence, the path to Canadian participation in ngVLA would be easier than for the SKA.