Author Archives: ecasseditor

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.

By Eric Steinbring (Canadian Gemini Office, National Research Council Herzberg Astronomy & Astrophysics)

New Opportunities

Something new in semester 2025A is an opportunity to get a live, virtual introduction to Gemini ahead of the deadline to complete Phase II (the definition of instrument setups that will be observed in queue). This is being offered via the Shadow the Scientists program; a Special Session set for 8 January 2025 at 4:30 AM in Hawai’i (6:30 AM Pacific and 9:30 AM Eastern). Intended especially for new users, but open to other Gemini users in 2025A, this is a chance to watch actual nighttime operations; learn how the queue is planned, get some insight on the Observing Tool, and understand how the Phase II process unfolds; and, of course, ask questions of the Observatory staff. As the queue (and weather) on Gemini-North allows there could be observations demonstrated with the Gemini Multi-Object Spectrograph (GMOS), Gemini Near-Infrared Spectrograph (GNIRS) or the MAROON-X high-resolution optical spectrograph.

And remember for next time that the time-exchange policy between Gemini and Subaru also makes those instruments available to Canadian astronomers, too. If you didn’t already know, here’s a new one on Subaru: the Prime-Focus Spectrograph (PFS) is a huge 2400-fibre spectrograph spanning 0.38 microns to 1.26 microns across a field-of-view of 1.25 square-degrees. Wow, that is big! Together with Gemini-South, there’s also all the other instruments on all three of these forefront telescopes – with access to the whole sky.

Upcoming Calls for Proposals

Gemini’s unique Fast Turnaround proposal process is a way to get new data quickly. The deadline for FT proposals is at the end of each month. The next is at 12PM (noon) Hawai’i time on 31 December, 2024, for observations from 1 February through 30 April 2025. They are easier to write, and shorter than a regular-semester proposal. Proposers agree to review some of the other proposals in exchange. So, this can even serve to get a little practice on both sides of that process, which can be good for early-career researchers. And historically, Canadians have learned how to do that well. The proposals need not be urgent (and Directors’ Discretionary time is always available to ask for, if that’s really the case) but it probably involves a small time request that could be observed sooner than the next regular CfP comes out. In fact, maybe it’s a pilot program for that bigger proposal, or some last quick observation which completes a previous dataset, or makes it more useful. Or just some timely idea to ask for. Canada has something like 20 hours per telescope per semester allocated to this mode. There were notably fewer applications than usual by Canadians for that time in the last semester; and it does not roll over. So, just a reminder to keep those good ideas coming – small or big. See: https://www.gemini.edu/observing/phase-i/ft/ft-cfp.

And coming up is the CfP for Gemini Large and Long Programs (LLPs) and Subaru Intensive Programs (SIP). These are not small ideas; instead being those bigger, more ambitious programs that may need more time than for a typical regular-semester program, or should be spread out over several semesters – or both. Brief Letters of Intent (LoI: https://www.gemini.edu/observing/phase-i/llp#Section1) are due early in February, which starts a planning exercise for considering what resources/instrument-scheduling may be needed and the organization of the review panel, prior to the actual full proposal deadline on 1 April, 2025. Note that, as I said, LLP on Gemini also means SIP on Subaru – available via the Gemini exchange-time policy – which makes that facility’s capabilities requestable by Canadians too. See the LLP CfP for more at https://www.gemini.edu/observing/phase-i/llp/.

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. Since mid 2023, the Coalition has been heavily engaged in lobbying for the CASTOR mission as the last of the three major astronomy infrastructure projects from LRP2010 and LRP2020 (VLOT and SKA being the others). A joint letter of support from Canada’s space industry community which emerged earlier this year continues to be an invaluable part of this effort. Coalition members continue to meet with members of parliament, as well with the presidents of NRC and CSA, to move the mission forward. The immediate, urgent priority continues to be 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.
• A highly productive CASTOR Technical Meeting was held in Victoria on November 12-14, with nearly three-dozen attendees from across Canada, the UK, USA and France. The meeting brought together researchers working on technology and software development under the UKSA CASTOR Bilateral Programme, NRC Small Teams project and other initiatives. Topics included an overview of the mission status and schedule; a summary of technical outcomes from the recently completed CSA Space Technology Development Program study; data archiving and processing efforts; survey scheduling simulations; simulations of the in-orbit performance of CASTOR’s expected flight detectors; simulations of the expected radiation environment and required detector shielding; a review of grating, DMD, and coating technologies for the UV; first results from CIS120 detector testing programs in Canada and the UK; a progress report on dichroic and coating approaches for red leak mitigation; a progress report on upgrades of the University of Calgary Vacuum UV Laboratory; a progress report on the development of readout and control electronics; a plan for space qualification of CASTOR’s flight detectors; and plans and priorities for the next steps in mission development.
• Detector Testing and Characterization Program. Upgrades to the vacuum ultraviolet calibration facility at the University of Calgary have been underway throughout most of 2024. This specialized facility is designed for testing and calibration of detectors that operate at UV wavelengths. Major upgrades have been carried out since the facility was last used for testing of the flight detectors for the Ultraviolet Imaging Telescope (UVIT) on Astrosat, which was launched in 2015 and continues to operate. Delta-doped CIS120 CMOS detectors from Teledyne-e2v and JPL have now been delivered to the facility, along with readout electronics provided by NRC-HAA; a test plan is now in place that will see testing and characterization carried out through most of 2025.
• CASTOR Overview Paper. In 2025, the Journal of Astronomical Telescopes, Instruments and Systems (JATIS) will publish a special issue entitled “Ultraviolet Science and Instrumentation: On the Way to Habitable Worlds Observatory and Beyond”. The CASTOR team has submitted an invited review for the mission, highlighting the current design, science plan, and ongoing technology development — with a focus on synergies with NASA’s Habitable Worlds Observatory (to be launched in the 2040s). The large number of coauthors (>160) reflects the many individuals who have contributed to the scientific, technical and programmatic development of the mission since 2010.
• Science Planning Tools. Students and postdocs continue to lead the development of a suite of science planning tools (FORECASTOR: Finding Optics Requirements and Exposure times for CASTOR). Ongoing projects include customized Pyxel-based simulations of the in-orbit performance of CASTOR’s expected flight detectors (led by Wasi Naqvi, UBC Okanagan) and an extensive suite of tools for implementation and scheduling of CASTOR’s legacy surveys (led by Michelle Kao, Waterloo), including a detailed trade study for CASTOR’s ground station network.
• Mid Term Review. The 2025 Mid Term Review of LRP2020 is now underway. MTR2025 “will offer an assessment of the status of the LRP2020 recommendations, an analysis of new opportunities, and recommendations to address emerging issues.” The CASTOR project has updated the MTR panel and JCSA on the mission status, new opportunities since LR2020, plans for future development, contributions from international partners as well as the expected schedule and timeline.

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

By Nadine Manset (Director of Science Operations, on behalf of the CFHT ‘ohana)

Recently

As proposed in its 10-year plan, CFHT offered up to 400 nights for Large Programs (LP) to be executed over a maximum of 1.5 years for MegaCam, and a maximum of 2 years for ESPaDOnS and SPIRou, in 2025 and 2026. NRC (Canada) and CNRS (France) offered up to 70% of their agency time for this round of Large Programs. CFHT is excited to announce that out of the 400 nights offered, 330 nights were
awarded to two MegaCam Large Programs, UNIONS+ and Pristine, and one SPIRou LP, PLANETS.

“UNIONS+: Securing the Imaging Legacy of CFHT” is led by Alan McConnachie (NRC Herzberg), S. Gwyn (CADC), and J.C. Cuillandre (CEA), and includes over 4 dozen Canadian co-I. The Ultraviolet Near Infrared Optical Northern Survey (UNIONS) is the definitive large area multi-band (u, g, r, i, z) ground-based wide-field survey in the northern hemisphere. UNIONS+ will extend the current coverage and contribute a total of 43% of the Euclid ground-based coverage. UNIONS is providing answers on its own to some of the most fundamental questions in astronomy, including the properties of dark matter, the growth of structure in the Universe from the very smallest galaxies to cluster scales, and the assembly of the Milky Way.

“PLANETS: PLanets, Atmospheres, and Nativity of ExtraTerrestrial worldS” is led by Jean-François Donati (IRAP/OMP) and includes multiple co-I from Canada, including E. Artigau (Université de Montréal), N. Cowan (McGill University), and over a dozen more. Building upon the extensive results of the SLS and SPICE LPs with SPIRou, PLANETS will now focus on very-low-mass nearby M dwarfs to unveil and characterize their planetary systems, on low-mass pre-main sequence stars whose accretion processes, inner accretion discs and inner planetary systems will be investigated to improve our understanding of star / planet formation, and on a handful of exoplanet atmospheres to be repeatedly scrutinized in order to accurately quantify their physical properties.

The Pristine LP will map the metallicity of the Milky Way system. Led by Nicolas Martin (Observatoire Astronomique de Strasbourg) and also including many Canadian astronomers (S. Fabbro and A. McConnachie from NRC Herzberg, A. McKay, F. Sestito, and K. Venn from University of Victoria, and a few more), the team will build on their extensive expertise of CFHT, MegaCam, and its excellent, metallicity-sensitive Ca H&K filter to push the Pristine survey that studies the oldest stars in the Milky Way to a new level. The observations will deconstruct the MW in its different environments (disk, halo, satellites) to enable a direct and thorough comparison with expectations from galaxy formation and evolution models. At the same time, any additionally uncovered extremely metal-poor stars ([Fe/H] <–3.0) with this LP program will contribute significantly to the hunt for the first generation of stars.

Additional details are available on the following page: https://www.cfht.hawaii.edu/en/science/LargePrograms/LP25A/

CFHT and the W. M. Keck Observatory again had the great honor to co-sponsor the Santa Float in the Waimea Twilight Christmas Parade on December 7th. The Christmas Parade was followed by a fun

Winter Star Party during which participants were able to take a look at the Moon, Saturn, and Jupiter. Hot chocolate and cookies were waiting for those who wandered inside our headquarters to look at our Remote Observer conducting observations.

Soon

If you happen to attend the AAS meeting in January, come by our booth, engage with the special session on Community Based Astronomy, or chat with us during the dedicated CFHT Evening Splinter Session. In January, we will also open the registration for the Users’ Meeting, which will be held May 26 – 28 at Lac-à-L’Eau-Claire, Québec. Preliminary information is available:
https://www.cfht.hawaii.edu/en/news/UM2025/venue.php

Mele Kalikimaka a me Hauʻoli Makahiki Hou!