CATAC Update on the Thirty Meter Telescope

par Michael Balogh (CATAC Chair)
(Cassiopeia – hivers 2020)

The recently published Canadian LRP2020 recommends, as its top priority for large ground-based facilities, “that Canada participate in a very large optical telescope (VLOT), and that this participation be at a level that provides compelling opportunities for Canadian leadership in science, technology and instrumentation”. The report notes further that this access is best implemented through “continued participation in TMT, either at the currently proposed Maunakea site or at the scientifically acceptable alternative of Observatorio del Roque de los Muchachos”. This is consistent with past recommendations and reaffirms the importance of VLOT access for the Canadian optical/infrared astronomy community in the coming decades. The leadership opportunities provided by TMT (or any VLOT) depend to some degree on the final share, governance model and construction timeline. CATAC expects that there will be more certainty about those factors over the next year, but with the information available today we agree that participation in TMT (at either site) represents the best route to fulfill the goals of the LRP.

LRP2020 also recommends developing and adopting “a comprehensive set of guiding principles for the locations of astronomy facilities and associated infrastructure in which Canada participates. These principles should “be centred on consent from the Indigenous Peoples and traditional title holders who would be affected by any astronomy project”. CATAC is aware that many Canadians are very concerned about how TMT construction in Hawai’i can be consistent with these principles, and that there has been important discussion within Canada about this. CATAC has raised these concerns with the Board. Our recommendation for continued support of TMT is based in part on the following considerations:

  • First and foremost, CATAC reaffirms our position that the decision about whether or not TMT is built in Hawaii should be entirely in the hands of the Hawaiian community, and that they are the only ones who should be responsible for defining what consent means within their own constituency.
  • CATAC awaits the full development of the guiding principles recommended by the LRP, which we hope and expect will be consistent with the previous point.
  • Recent developments have led to an opportunity for renewed dialogue within Hawai’i, that CATAC believes is consistent with the views expressed in our LRP, and the white papers on Indigeneous rights submitted to that process. These discussions are taking place among diverse groups, and involve not only TMT but all astronomy on Maunakea, as well as many broader issues of Hawaiian society. We describe some of these developments below, and note there are more details in our recent report to the CASCA Board, which is available on our website. It is vitally important to give these discussions the time and space they need. They are connected to concerns that are much broader than TMT, or astronomy.

Telescope Site, Partnership and Construction Timeline

On August 13, in response to the initial planning proposal for the US Extremely Large Telescope Program (ELTP), the US National Science Foundation (NSF) announced the initiation of an informal outreach process to engage people and groups interested in the Thirty Meter Telescope (TMT) project. Hawai’i House Speaker Saiki issued a press release about this on Aug 18. This outreach is a precursor to an NSF decision about whether or not to accept the ELTP proposal and formally join the project.

This engagement on the part of the NSF is welcomed by the TMT International Observatory (TIO) Partners, and brings a new opportunity for a Hawaiian consultation process and formal review, led by a widely respected body. It also establishes a timeline of events that will take place over the next 12-18 months, each of which will provide increasing clarity over the future viability of TMT:

  • The US Astro2020 process is anticipated to release their public report in mid-2021. A top ranking in this report is essential for NSF engagement and the viability of the project. The report may make other recommendations relevant to TMT.
  • Should the NSF accept the ELTP proposal, this will trigger a federal Environmental Impact Statement (EIS), which will take about three years to complete. Included as part of this review would be the important Section 106 process of the National Historical Protection Act. This would have the significant effect of leading to a federally recognized record of the importance of Maunakea to Hawaiians. Information from the public consultation phase of this process will shed further light on the situation as the review progresses. We note that a federal EIS may also be required at La Palma if the NSF is a partner.
  • Upon acceptance of the proposal, NSF will also conduct an in-depth Preliminary Design Review, likely in late 2021. This is a comprehensive review of all aspects of the project, including operations and a detailed costing.

Assuming TMT construction cannot begin until the EIS has completed (which may not be the case), construction might not start before 2023. An estimate of seven years construction and three years commissioning would mean first science in 2033 or later. The main competition for TMT is the ESO Extremely Large Telescope (ELT) project. The ELT is currently under construction, and current planning anticipates technical first light (TFL ) by the end of 2025, though the COVID-19 pandemic may add some delay. It is planned that all four first-light instruments would be commissioned within two to three years after TFL. Assuming no delays to that project, the gap to TMT science could be six years. But, at this point, there is enough uncertainty in the timeline of both projects that the gap could be larger, or smaller.

In parallel with these NSF-led consultations, there are several other important discussions and activities underway in Hawaii. These include:

  • In May, 2020, the Department of Land and Natural Resources (DLNR) launched an independent review of the University of Hawaii (UH) management of Maunakea as part of the Master Lease renewal process. The independent Hawaiian consultation group Ku`iwalu, has been engaged to evaluate the effectiveness of the UH and the OMKM in its implementation of the Comprehensive Management Plan (CMP). Some information about the process underway is available at their website. At the time of launch, the review was expected to conclude by the end of 2020, though this may be delayed.
  • An important part of Governor Ige’s proposed path forward for TMT on Maunakea is the decommissioning of “as many telescopes as possible”. This process is underway, through the OMKM. Decommissioning is a lengthy process, as it involves its own Environmental Assessment and DLNR permit preceding the physical removal of the facility and complete restoration of the site. Decommissioning of the UH-Hilo teaching telescope, Hoku Kea is expected to be completed in 2023. The Caltech Submillimeter Observatory decommissioning is anticipated to be completed in 2022.
  • Multiple groups in Hawaii are meeting to discuss broad issues such as housing, education and land ownership, including the role of astronomy. Among these groups are the Hawai’i Executive Collaborative and the ‘Aina Aloha Economic Futures. Participants in these meetings include TMT opponents. Canadians associated with TMT have also been invited to participate in some of these discussions, though the travel restrictions associated with the pandemic have significantly affected this effort.

Instrumentation Update

The TMT Exoplanet Roadmap Committee is considering the prioritization of desired exoplanet capabilities for planned second-generation TMT instruments: PSI, MICHI and HROS. The prioritization would be a function of the various instrument modes (imaging, spectroscopy, polarimetry) and their implementation (resolution, IFU, choice of wavelengths/bands). Input from the Canadian community is welcome, before mid-January. A short summary of proposed capabilities together with an Excel template for feedback are available on the CATAC web page.

Project Office Update

Dr. Gary Sanders, who has led the TMT Project as Project Manager with distinction since its inception, will retire at the start of 2021. Deputy Project Manager Fengchuan Liu, who has worked closely with Gary and co-directed the project for the last five years, will assume the Project Manager (acting) position while TMT searches for a permanent project manager.

President’s Message

By / par Sara Ellison (CASCA President)
(Cassiopeia – Winter / hivers 2020)

The Long Range Plan is out! This final report represents two years of effort in our community to examine the state of our professional activities and ambitions from both a scientific and societal perspective. Hundreds of people in our community have contributed in a variety of ways to the generation of this finished product, ranging from co-authoring white papers, attending town hall meetings and dedicated AGM sessions, to providing feedback to the panel along the journey. A broad message of gratitude is therefore due to the entire community for your engagement and collaboration. As a Society, we owe our greatest thanks to the LRP panel for the immense undertaking of leading this process: Pauline Barmby, Matt Dobbs, Bryan Gaensler, Jeremy Heyl, Natasha Ivanova, David Lafreniere, Brenda Matthews and Alice Shapley. The French version of the LRP, as well as the typeset version with full figures and design and hard copies, are expected early in the new year.

As alluded to in my last President’s message, the next challenge in the LRP process is its implementation, and the Board (with input from the current LRPIC, as well as LRP co-chairs) has been laying out the strategy for this next step. Oversight and monitoring of both existing and future facilities will remain in the remit of our current CASCA committees: the Ground-based Astronomy Committee (GAC, currently chaired by Stefi Baum) and the Joint Committee on Space Astronomy (JCSA, currently chaired by Locke Spencer). In order to tackle the broad ranging community-based LRP recommendations, CASCA will create a new committee, the LRP Community Recommendations Implementation Committee (LCRIC), whose portfolio will encompass the societal-level aspects of the plan, including equity, indigenous matters, outreach and sustainability. The LCRIC will work to generate an actionable implementation plan from the LRP’s recommendations, working with existing CASCA committees and striking new working groups as needed to convert the recommendations into reality over the next decade. We are just beginning the first steps in establishing this new LCRIC, but I am delighted to announce that Christine Wilson (McMaster University) has agreed to be the inaugural Chair. Given their remit, the new LCRIC, in partnership with the GAC and JCSA, will replace the previous LRPIC – I thank John Hutchings and his team for their wisdom and tireless efforts over many years.

The top (unfunded) large facilities in the LRP are the SKA and CASTOR. As discussed in my September message, the SKA is reaching a critical point with the IGO expected to take over the project imminently. Securing membership and funding for Canada has been at the top of CASCA’s agenda of effort over the last few months. I have been working closely with Kristine Spekkens (Canadian SKA Science Director) and Gilles Joncas (AACS Chair) to prepare the ground for the Coalition’s lobbying activities. These activities are now well underway with a positive first meeting with officials from ISED, and more in the planning stages. In collaboration with ACURA, the AACS has also mobilized its university connections, with several VPR briefings already completed across the country. I encourage you to look at the Canadian SKA webpage, which hosts a wealth of material on the project, its science aspirations, industry connections and societal impacts. In particular, I point you to a handy 4-page summary of the project in the Canadian context, in case you have the opportunity to discuss the project in your broader networks.

With an anticipated launch in the late 2020s, there is also significant on-going progress on planning for the CASTOR space telescope. A more complete report is provided by Pat Côté in this Edition, but the long-awaited CSA technical study request for proposals (STDP RFP) has now been issued (and, by the time you read this, closed), representing a significant step in the preparatory process. CASTOR is one of seven “Priority Technologies” in this call, and there are five different work packages within the CASTOR study. The CSA has also started working a mission development plan for CASTOR: i.e., a summary of timelines, budget requirements, milestones and action items that mark the path towards launch later this decade. CASTOR represents a truly unique and exciting component in Canada’s astronomy portfolio – the potential for a Canada-led UV-optical space telescope will not only bring terrific science returns, as well as showcasing and supporting our national expertise in several technology domains, but it will generate tremendous excitement and pride in the general public, inspiring the next generation of budding scientists and engineers.

On the digital infrastructure side, the New Digital Research Infrastructure Organization (NDRIO) is ramping up to eventually replace Compute Canada. Unlike Compute Canada, NDRIO is funded directly by ISED, and CASCA is an Associate Member (as is CADC). NDRIO held its first AGM at the end of September, at which the inaugural Researcher Council (RC) was announced. Erik Rosolowsky (U of A) was one of approximately 20 appointees on the new RC. Despite this success, it is the responsibility of our broader community to engage with NDRIO and communicate our needs. Notably, astronomy represents ~5% of Compute Canada users but uses ~20% of its resources. Our success as a field therefore critically relies on effective and appropriate DRI. NDRIO has outlined several steps in its initial consultation process on needs assessment within the broader community. Several white papers are under preparation within our astronomy community in response to the first step in this call. A user survey is also expected in the near future – please take the time to complete this survey when it comes your way!

Preparations for the CASCA 2021 AGM (May 10-14) continue apace – since CASCA was founded in 1971, this will be our 50th birthday party! The SOC and OOC have developed an exciting scientific and social program for CASCA 2021. With the release of the LRP, and the broad reaching issues it has assessed, the SOC has chosen a theme that will align with the LRP2020’s goals: « Canadian Astronomy: Dialing It Up To 11 ». The SOC has selected a roster of invited speakers and the invitations will have been sent by the time you read this. The organizing committees have scored quite the coup with securing recent Nobel laureate Professor Andrea Ghez to present the Helen Sawyer Hogg Public Lecture. Two other ‘evening’ events have been planned. There will be a games night featuring the popular game ‘Among Us’ and the CASCA Banquet will feature « CASCA Has Talent » – a chance for CASCA members to demonstrate their non-astronomy skills. The OOC is also working on integrating daily social interactions; it won’t be quite the same as being together in Penticton, but it sounds like it will be a lot of fun nonetheless! Watch this space in the new year for more details and registration.

Plan à long terme 2020

From Pauline Barmby, Bryan Gaensler (LRP2020 co-chairs PLT2020)
(Cassiopeia – Winter / hivers 2020)

Au nom de Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David Lafrenière, Brenda Matthews et Alice Shapley, nous sommes heureux de présenter le rapport final du Plan à long terme 2020 de la CASCA pour l’astronomie canadienne (PLT2020). La version non formatée du rapport est désormais disponible sur le site Web de CASCA. Une version conçue par des professionnels et une traduction en français sont en cours et devraient être disponibles au début de 2021.

Nous remercions tous ceux qui ont contribué à ces recommandations en rédigeant un livre blanc, en assistant à une discussion communautaire, en participant à des consultations ou en répondant à nos nombreuses demandes d’informations. Nous voudrions particulièrement souligner le travail très dur des membres du panel PLT2020 au cours des vingt derniers mois. Nous remercions également les agences dont le soutien financier a permis le processus PLT2020, et le conseil d’administration de la CASCA de nous avoir confié la direction de cet exercice.

Ce sera notre dernière mise à jour Cassiopeia. La section PLT2020 sur le site Web de la CASCA contient des liens vers tous les livres blancs et rapports soumis ainsi qu’un résumé du processus. Les versions conçues et traduites du rapport y seront disponibles quand fini.

Graduate Student Highlights

By Carter Rhea (Chair, CASCA Graduate Student Committee)
(Cassiopeia – Winter / hivers 2020)

Mainak Singha — Université du Manitoba

La recherche de Mainak portent sur la façon dont la faible accrétion des « noyaux galactiques actifs » (AGN) peut stimuler les processus d’évolution des galaxies. La plupart des modèles d’évolution des galaxies qui réussissent nécessitent que l’AGN lance des flux à l’échelle galactique pour diriger les processus d’évolution des galaxies. Afin de retracer les signes de ces flux, il utilise les données spectroscopiques (spectres) du SDSS (Sloan Digital Sky Survey). Les raies d’émission de ces spectres mettent en évidence l’ionisation causée par les photons des disques d’accrétion de l’AGN ou les chocs de l’AGN. Toute asymétrie dans les profils des lignes d’émission indique que le gaz se rapproche ou s’éloigne de nous, ce qui est la signature de flux sortants.

Figure 1

Figure 1: Diagramme standard BPT du SDSS DR7. La radiogalaxie J142041+025930 se trouve dans la région LINER (Low Ionization Nuclear Emission Line Region) de la partie suggérant qu’il s’agit d’une radiogalaxie à faible excitation (LERG).

Vivian Tan — Université York

Les recherches de Vivian se concentrent sur les galaxies qui résident au sein des amas de galaxies à des décalages vers le rouge de 0.25 < z < 0.6, dans les Hubble Frontier Fields. Les amas sont des environnements dynamiques où les galaxies interagissent et s’éteignent, ce qui signifie le passage de la formation d'étoiles à la phase de repos. Les processus d'éteignant modifient la morphologie d'une galaxie, dont nous voulons mesurer non seulement par leurs profils de lumière, mais aussi par leur distribution de masse stellaire. La cartographie de la masse stellaire d'une galaxie est généralement difficile à z > 0, mais les Frontier Fields disposent d’une photométrie Hubble multibande profonde. Cela signifie que des cartes de masse stellaire résolues sont possibles même pour des galaxies aussi petites que 108 masses solaires. Les galaxies ayant des masses stellaires aussi faibles n’ont pas été étudiées de manière résolue à z > 0. Comme nous pouvons analyser la morphologie avec des cartes de masse stellaire résolues, nous avons constaté que les galaxies quiescentes qui sont moins massives que 109.5 masses solaires sont plus susceptibles d’être dominées par un disque (indice de Sersic ~ 1 à 2), mais les galaxies quiescentes sont dominées par un bulbe au-dessus de cette limite de masse (indice de Sersic de 4 ou plus). Ce phénomène n’a été constaté que dans les amas, mais pas dans les environnements « de champ » moins denses. Cela signifie que différents processus d’extinction ont dû se produire pour transformer ces galaxies, et ces processus d’extinction dépendent à la fois de la masse des galaxies et de leur environnement.

Figure 2

La figure 2 montre le processus de création des cartes de masse stellaire résolues par un processus appelé « SED-fitting ». La galaxie est divisée en compartiments spatiaux, et un SED est ajusté au flux photométrique de plusieurs bandes dans chacun des compartiments. La SED ajustée peut révéler la masse stellaire de cette région de la galaxie et, en rassemblant tous ces éléments, on obtient une carte de masse stellaire résolue. Les mesures de l’indice Sersic de la masse stellaire sont obtenues par ajustement paramétrique d’un profil Sersic 2D directement sur la carte de la masse stellaire à l’aide de GALFIT.

Jessica Campbell — Université de Toronto

Les recherches de Jessica se concentrent sur la nature multiphasique du champ magnétique de notre Galaxie et sur la façon dont il se connecte entre les différentes phases du milieu interstellaire (ISM). Que ce soit le milieu ionisé chaud turbulent (WIM) qui remplit une grande partie de la Galaxie ou le milieu neutre froid (CNM) que l’on trouve souvent dans les feuilles et les filaments, ce milieu ISM complexe est imprégné de rayons cosmiques et de champs magnétiques de haute énergie. Lorsqu’ils sont accélérés par le champ magnétique, ces rayons cosmiques émettent un rayonnement radio synchrotron fortement polarisé linéairement. Lorsque cette émission polarisée passe à travers l’ISM de premier plan, les électrons thermiques et les champs magnétiques de l’ISM font tourner le plan de polarisation, un effet appelé rotation de Faraday. Ces rayons cosmiques peuvent également pénétrer et ioniser les régions les plus denses de l’ISM, ce qui fait que même le milieu essentiellement neutre est couplé au champ magnétique par des structures HI linéaires de 21 cm appelées « fibres HI ». Malgré la richesse des informations sur le champ magnétique de l’ISM et du CNM, on sait très peu de choses sur leurs relations mutuelles. Les milieux diffus ionisés et froids en touffes partagent-ils un champ magnétique commun ? Si oui, à quelle fréquence et dans quelles circonstances cela se produit-il ? Telles sont les questions qui motivent les recherches de Jessica.

Figure 3

La figure 3 montre l’émission de poussière de Planck à 353 GHz, où l’image en couleur représente l’intensité totale (non polarisée) et les lignes texturées indiquent l’orientation du champ magnétique. L’émission de poussière contient clairement les mêmes morphologies de genou et de fourche, et l’orientation du champ global est à peu près parallèle aux filaments polarisés F1 et F3.

Robert Bickley — Université de Victoria

La recherche de Robert se concentre sur l’interaction entre l’astronomie observationnelle et l’apprentissage automatique. Il utilise les techniques visuelles pour identifier les galaxies qui ont subies récemment les fusions avec une autre galaxie. Ces fusions ont une signature distincte – elles créent des morphologies bizarres et déplacent les étoiles qui appartiennent aux galaxies. Pour identifier les fusions en utilisant l’apprentissage automatique, il entraîne les réseaux au neurones convolutifs sur les fusions (et non-fusions) prises de la simulation bien connue: IllustrisTNG. Il les utilise d’entraîner, valider, et tester les réseaux.

Figure 4

La figure 4 démontre l’habileté du réseau à identifier les fusions comme une fonction de leur environnement. Si une galaxie a une voisine proche, sa valeur de r_1 va être petite; par contre, s’il n’y a pas de voisine, la valeur de r_1 va être tellement grande. Le panneau en haut démontre le nombre total de fusions et les contrôles (bleue et orange). De plus, il catégorise les classifications comme correcte ou incorrecte (fp, brun: contrôle classifié comme un fusion; tn, violet: contrôles bien-classifiées; fn, rouge: les fusions classifiées comme des contrôles; tp, verte: fusions bien-classifiées). Le panneau en bas montre la fraction de fusions et galaxies de contrôle qui sont identifiées correctement par le réseau.

Rapport final de PLT2020

Chers collègues:

Au nom de Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David Lafrenière, Brenda Matthews et Alice Shapley, nous sommes heureux de présenter le rapport final du Plan à long terme 2020 de la CASCA pour l’astronomie canadienne (PLT2020). La version non formatée du rapport est désormais disponible sur le site Web de CASCA sur . Une version conçue par des professionnels et une traduction en français sont en cours et devraient être disponibles au début de 2021.

Nous remercions tous ceux qui ont contribué à ces recommandations en rédigeant un livre blanc, en assistant à une discussion communautaire, en participant à des consultations ou en répondant à nos nombreuses demandes d’informations. Nous voudrions particulièrement souligner le travail très dur des membres du panel PLT2020 au cours des vingt derniers mois.

La section PLT2020 sur le site Web de la CASCA ( contient des liens vers tous les livres blancs et rapports soumis ainsi qu’un résumé du processus. Les versions conçues et traduites du rapport y seront disponibles quand fini.

Pauline Barmby & Bryan Gaensler
co-présidents PLT2020

Rapport final de LRP2020

Au nom de Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David Lafrenière, Brenda Matthews et Alice Shapley, nous sommes heureux de présenter le rapport final du Plan à long terme 2020 de la CASCA pour l’astronomie canadienne (PLT2020). La version non formatée du rapport est désormais disponible sur le site Web de CASCA. Une version conçue par des professionnels et une traduction en français sont en cours et devraient être disponibles au début de 2021.

Nous remercions tous ceux qui ont contribué à ces recommandations en rédigeant un livre blanc, en assistant à une discussion communautaire, en participant à des consultations ou en répondant à nos nombreuses demandes d’informations. Nous voudrions particulièrement souligner le travail très dur des membres du panel PLT2020 au cours des vingt derniers mois.
La section PLT2020 sur le site Web de la CASCA contient des liens vers tous les livres blancs et rapports soumis ainsi qu’un résumé du processus. Les versions conçues et traduites du rapport y seront disponibles quand fini.

Pauline Barmby & Bryan Gaensler
co-présidents PLT2020

Pauline Barmby

Prof. Pauline Barmby
Associate Chair, Undergraduate Programs
Department of Physics & Astronomy, Western University

Canadian Astronomy, Racism, and the Environment – Part 1

By / par Martine Lokken, Chris Matzner, Joel Roediger, Mubdi Rahman, Dennis Crabtree, Pamela Freeman, Vincent Henault-Brunet (The CASCA Sustainability Committee, The CASCA Equity & Inclusivity Committee)
(Cassiopeia – Autumn / l’automne 2020)

Part 1: An Introduction to Environmental Racism

This year’s widespread protests in support of Wetʼsuwetʼen sovereignty, and in support of Black lives in the face of police brutality, have brought heightened attention to the racism and systemic racial inequalities that have long threatened Indigenous and Black people in North America. The astronomy community has been coming to terms with its own systemic racism [1], and it is important that we examine our field’s environmental impacts [2] through the same lens. In this moment, we in CASCA’s Sustainability Committee reflect on the many ways in which environmentalism and racism interact. Here we present some background on how these issues are intertwined with the climate crisis and environmental damage both globally and within Canada. In a later article with the Equity & Inclusivity Committee we will ask how we as astronomers have benefitted from and perpetuated racism, environmental or otherwise, and what we can do to change this.

The climate crisis is projected to deal a sequence of crushing blows to peoples of the arctic, equatorial, and oceanic regions of the world. Of those affected, the UN warns that Indigenous peoples face the most climate-based disruption because of their strong cultural and economic connections to the land on which they live [3]. Indeed, this has already begun [4]. Drought now affects a quarter of the world’s population, mainly in equatorial regions [5], leading to food insecurity and mass migration [6, 7]. Heat waves are on the rise, some now surpassing what humans can naturally survive [8]. Last year, massive fires decimated the Australian landscape, damaging perhaps thousands of Indigenous cultural sites [9], while deliberate fires ate away at the home of the Amazon’s Indigenous people. This year’s Amazon fires could be even worse [10], and record heat waves are intensifying annual wildfires in Siberia [11]. Vast floods have covered a quarter of Bangladesh [12], while rising seas are swallowing island nations [13]. The distribution of global wealth plays a major role in deciding who can best survive these extreme events: while wealthy areas of developed nations are able to adapt to some of the effects of climate change through investment in infrastructure, the world’s poorest are disproportionately losing their homes, livelihoods, and even lives [14]. Meanwhile, the worst per-capita contributors to the climate crisis are primarily located in the northern hemisphere [15] and led by wealthy nations such as Canada, the U.S., Australia, Saudi Arabia, and other major oil-producing countries. The disparities between the worst perpetrators of the climate crisis versus those who suffer the greatest impacts correlate with inequalities of wealth, power, and territory that have been sown over the long history of European colonialism, and are reinforced by systemic racism.

Canada is no exception to this. Our country has a tragic history of slavery, anti-Indigenous and anti-Black racism, and attempted erasure of Indigenous cultures. Much of our wealth is based on the exploits of land which often was cheated or taken by force from Indigenous nations [16, 17]. We are currently the fourth largest producer and exporter of oil [18], and the average Canadian’s contribution to the climate crisis is among the world’s greatest [19]. However, unsurprisingly, systemic racism plays a major role in who has benefitted from this wealth versus who is most impacted by the environmental damage.

Many rural Indigenous communities in Canada are disproportionately feeling the effects of climate change. Ice roads, which in the winter enable goods to reach northern communities, become unavailable or unsafe as temperatures rise [20]. Melting ice and extreme weather is cutting Inuit people off from traditional hunting lands, severely threatening people’s physical and mental health [21]. In Eastern Indigenous communities, rising sea levels have negatively impacted traditional medicines and food supplies by increasing the salination of freshwater [22]. In addition to the unintentional impacts from climate change, there are also many situations in which racist planning for polluting sites such as factories, mills, and pipelines have caused environmental harm to rural Indigenous communities. For example, for 53 years the Northern Pulp mill in Nova Scotia treated its effluent in Boat Harbour (A’se’k), a tidal estuary upon which the Pictou Landing First Nation depended for food, livelihoods, and culture. Only this year, after years of community activism, has the provincial government ended the pollution of Boat Harbour, allowing its restoration to begin [23]. These various stresses to rural communities can spur an exodus to urban centers, leading to the loss of languages and cultures that are often deeply connected to the local environment [22, 20].

Systemic racism has also resulted in various environmental disparities for racialized communities in urban areas. The Canadian government warns of the dangers of urban heat islands, areas which amplify warm temperatures due to an excess of paved surfaces and lack of green space [24]. Populations more at risk for heat-related illness include Indigenous people, newcomers to Canada, and poor people [24]. The systemic effects which cause higher poverty rates among racialized people [25] and a lack of heat-protecting infrastructure in poor neighborhoods combine to make racialized Canadians more vulnerable to rising heat waves. (Because of Canadian astronomy’s connections to the U.S., it is also worth noting that the long-lasting effects of racist redlining in many U.S. cities have resulted in heat islands being centered on predominantly Black neighborhoods there [26, 27].) In addition to heat, pollution is another major health issue in urban centers. Similar to Pictou Landing, there are many cases of polluting sites being built near Indigenous or Black communities in urban areas (e.g. “Chemical Valley”, ON [28] and Africville, Nova Scotia [29]). These compounding environmental effects can cause serious health problems in marginalized communities, such as higher cancer rates and respiratory issues [28, 30], increased heat-related illnesses [30], poisoning from high levels of dangerous materials in water sources (e.g. Grassy Narrows, ON [31]), and worse pregnancy outcomes faced by Black mothers [U.S. data, 32]1.

The disproportionate effect of the climate crisis on racialized communities is exacerbated by the casual and systemic racism often present in predominantly-white environmental circles and the policies put forth by them. An important example of this is the centrality of the overpopulation argument to many Western approaches to the climate crisis, including in scientific circles [33]. While regularly debunked by public health scholars with the topical expertise in this area [34,35,36], racist origins and implications have been used to advance racist policies in the name of environmental sustainability [37,38]. This interplay has acted to shift the blame from the consumption of the Global North and casts the blame on the Global South, including some of the very populations that are most susceptible to the effects of the climate crisis.

Therefore, although the climate crisis will affect everyone to some extent, it is important that we recognize how global and local histories of racism and colonialism factor into the equation. Those of us with the privilege to be relatively insulated from environmental damage — at least for now — must especially examine our environmental impact and our complicity in systems of oppression. In doing so, it is essential that we learn from the BIPOC leaders who have historically spearheaded the movement for environmental justice like Dr. Robert Bullard and the Rev. Benjamin Chavis [39] and listen to the young voices, such as Makasá Looking Horse, who are taking the reins [40]). In our next article, we will examine how Canadian astronomy has benefitted from and continues to partake in white supremacist systems while also contributing to environmental injustice. We will discuss how to change the status quo, considering issues such as respect for Indigenous land rights and frequency of academic flights.

1Canada doesn’t require collection of race-based health data, an issue which has gained awareness during the Covid-19 pandemic (
The general taboos around studying the effects of race in Canada partially explain why there are fewer available resources on environmental racism here than in the US.


  34. Rosling, H., Rosling Rönnlund, A. and Rosling, O., 2019. Factfulness. Paris: Flammarion.

CATAC Update on the Thirty Meter Telescope

By / par Michael Balogh (CATAC Chair)
(Cassiopeia – Autumn / l’automne 2020)

The COVID-19 pandemic and the ongoing discussions with all stakeholders about site access continue to delay the start of TMT construction, and in mid-July the TMT International Observatory announced that no on-site construction activity would take place this year. However, progress continues to be made on technical components, including development of instrumentation. A notable milestone was the interim Conceptual Design Review of the Wide Field Optical Spectrograph, held in July. This review provided important guidance on the work and planning needed to bring it to a full Conceptual Design level. In addition, over the summer several critical systems completed their Preliminary Design phases and are now ready to move into Final Design. These include the Engineering Sensors System, the Instrumentation Cryogenic Cooling System, and the Optical Cleaning System.

The US-Extremely Large Telescope Project (ELTP) is a collaboration between NSF’s NOIRLab, TMT and the Giant Magellan Telescope (GMT). Its mission is to “strengthen scientific leadership by the US community-at-large through access to extremely large telescopes in the Northern and Southern Hemispheres with coverage of 100 percent of the night sky”. Over the summer, this group has submitted several proposals to the US National Science Foundation (NSF) for the design and planning of the ELTP. In response to one of these proposals, NSF recently issued a three year award to AURA and NOIRLab for the “development of detailed requirements and planning documents for user support services”. See the update here.

The TMT project will face several critical milestones in the next year or so. These will be important for defining the future of the project and addressing some of the questions and concerns that are on the minds of the TMT partners, including Canada. These milestones include:

  • The release of the US Decadal Survey recommendations, expected in the first half of 2021
  • Initial findings from any Environmental Impact Survey (EIS) conducted by the NSF as a result of its engagement in the project
  • The full cost and schedule review that is currently being undertaken by the Project Office

Success at each of these stages is necessary, though not sufficient, for the project to proceed as envisioned.

The alternative site at ORM remains under consideration. CATAC has seen a draft of a report by the Japanese partners on the scientific quality of ORM, which largely comes to the same conclusions we did in our 2017 report. For the time being, we expect the focus to remain on Maunakea until the outcome of the federal EIS is known.

Due to the ongoing discussions and assessments of building on Maunakea, and the processes needed to secure NSF as a new partner, construction may not start until 2023 or later. With a reasonable estimate that first light may not come until about ten years after that (seven years construction plus three years commissioning), science operations with TMT could commence in the mid 2030s. This schedule is not likely to be significantly different if the alternative site is selected. Currently, Canada’s share of the construction costs is estimated to be about 15%, but this will be reevaluated once the Cost Review and negotiations with the NSF are completed.

CATAC membership:
Michael Balogh (University of Waterloo), Chair,
Bob Abraham (University of Toronto; TIO SAC)
Stefi Baum (University of Manitoba)
Laura Ferrarese (NRC)
David Lafrenière (Université de Montréal)
Harvey Richer (UBC)
Kristine Spekkens (Royal Military College of Canada)
Luc Simard (Director General of NRC-HAA, non-voting, ex-officio)
Don Brooks (Executive Director of ACURA, non-voting, ex-officio)
Sara Ellison (CASCA President, non-voting, ex-officio)
Kim Venn (TIO Governing Board, non-voting, ex-officio)
Stan Metchev (TIO SAC, non-voting, ex-officio)
Tim Davidge (TIO SAC Canadian co-chair; NRC, observer)
Greg Fahlman (NRC, observer)

Graduate Student Highlights

par Carter Rhea (Chair, CASCA Graduate Student Committee)
(Cassiopeia – été 2020)

Each month, the GSC highlights the work of an outstanding Canadian graduate student by sharing their work with our members. Since the launch in February of 2020, we have highlighted four students from around the country.

Follow us on Twitter, Instagram, and Facebook under the handle casca_gsc.

Christian Thibeault — L’Université de Montréal

Les éruptions solaires sont des tempêtes de rayonnement provoquées par la libération d’énergie magnétique provenant de la couronne solaire. Ces éruptions posent un danger pour les astronautes et peuvent causer des perturbations importantes sur les communications satellites (incluant les systèmes GPS). Il a été proposé par E.T Lu et ses collaborateurs que les éruptions solaires sont le produit d’une réaction en chaîne inobservable de reconnexions magnétiques à petite échelle. Cette cascade de petits évènements peut être simulée avec un simple modèle sur réseau, appelé « modèle d’avalanche ». Le but de mon projet de maîtrise est d’évaluer le potentiel de ces modèles à faire des prédictions à court terme des éruptions solaires. Nous avons tout d’abord étudié le comportement stochastique de plusieurs modèles d’avalanche, et sommes maintenant en train d’intégrer l’assimilation de données sur des observations de rayon X (GOES) des éruptions solaires pour améliorer nos prédictions.

Figure 1 – Représentation imagée de l’interprétation physique d’une boucle coronale qui accumule de l’énergie par rotation de sa base. (Strugarek et al. 2014)

Mallory Thorp — University of Victoria

Comme une chercheuse en Astronomie, elle enquête comment changent-ils les galaxies au cause d’une fusion majeure galactique — ça se passe quand deux galaxies d’au peu près la même taille s’interagissent y se fusionnent en une unique galaxie. Pour meilleure comprendre ces changements d’un ordre de grandeur de quelques kiloparsecs, elle utilise les measures de la Spectroscopie de Champs Intégral (IFS – Integral Field Spectroscopy en anglais) d’enquête La Cartographie des Galaxies Proches à l’Observatoire d’Apache Point (MaNGA – Mapping Nearby Galaxies at Apache Point Observatory en anglais). L’IFS lui fournit une spectre pour chaque pixel d’une image d’une galaxie qui nous permet d’examiner comment les produits-de-données spectrales — comme le taux de formation stellaire (SFR — Stellar Formation Rate en anglais) — se changent à travers une galaxie.

On peut voir dans le figure 2 trois exemples de galaxies post-fusion de MaNGA (première colonne) et leurs cartes de densité surfacique de SFR (deuxième colonne). En comparant les cartes de SFR de galaxies post-fusion avec les galaxies isolées, nous pouvons quantifier le changement en SFR à la suite de fusion. La troisième colonne montre l’augmentation de SFR causée par une fusion en bleue, tandis qu’un déficit est visualisé en rouge. En moyenne, les galaxies post-fusion éprouvent une augmentation à travers la galaxie entière en SFR (voir les deuxième et troisième fusions). Les variations de ça, comme l’étouffement de SFR en les régions lointaines de la première galaxie post-fusion, peut-être indiquer comment les qualités progénitures distinctes et orientations modifient l’efficacité de la formation des étoiles.

Cette travaille-là était complétée par moi-même sous la direction de Sara Ellison (Nous deux sommes les membres de CASCA!)

Figure 2

Lingjian Chen — Saint Mary’s University

Dans ma recherche, j’étudie l’environnement galactique. Les environnements denses, tels que les groupes et les amas de galaxies, sont formés, en partie, par les fusions hiérarchiques. La distribution de galaxies satellites nous indique comment les galaxies dans cet environnement évoluent.

Nous étudions la distribution radiale des satellites autour de galaxies centrales en utilisant les données de Hyper Suprime-Cam (HSC) Subaru Strategic Program (HSC-SSP) et le télescope de Canada-France-Hawaii (CFHT) Large Area U-band Deep Survey (CLAUDS). Grâce à cette région étendue, la photométrie de 6-bandes et la profondeur du survey, nous pouvons identifier plus que 5000 centres dans un décalage vers le rouge entre 0,3 et 0,9. En plus, nous pouvons identifier les satellites qui sont en orbite autour de galaxies centrales.

Nos résultats nous indiquent que la distribution de densité de satellites est bien décrite par un profil NFW (Navarro-Frenk-White 1995, qui est normalement utilisé pour décrire le profil de densité de matière sombre) en une échelle plus grande que 100 kiloparsec à un décalage vers le rouge bas (e.g. Tal +2012). Nous avons enquêté en plus la dépendance de la distribution entre les satellites et les propriétés de la galaxie centrale. Nous trouvons que le mécanisme qui forme la distribution de satellites est relié fortement au frottement dynamique et le décapage des étoiles. Cependant, on a besoin de faire plus de simulations détaillées.

Le figure 3 démontre les galaxies de type satellite. La galaxie centrale est indiquée par un cercle jaune, les galaxies de type satellite potentielles sont indiquées par un cercle vert, et le rayonnement de sélection est indiqué en rouge (700 kpc). Les galaxies centrales étaient identifiées par leur masse et les critère d’isolation. En utilisant la différence en photo-z et une région circulaire, on a choisi les galaxies de type satellite. Le numéro des galaxies de type satellite montré ici était corrigé par les objets de fond.

Figure 3

Le figure 4 montre la densité superficielle des galaxies de type satellites (la moyenne) autour une galaxie centrale après la correction pour les objets de fond. La ligne solid démarque la meilleur ajustement et peut être séparée en deux composantes: la composante NFW au grandes échelles et la composante Sersic au petites échelles.

Figure 4

Farbod Jahandar — L’Université de Montréal

Farbod Jahandar travaille à débrouiller les mystères chimiques de nos étoiles voisines. Pour faire ça, il étudie les observations à haute résolution des naines étoiles de type spectral M qui sont les étoiles les plus nombreuses dans notre galaxie et sont les étoiles les plus petites et les plus froides sur la séquence principale. Cette analyse a un impact puissant sur plusieurs domaines en astronomie; en particulier, ça nous permet de déterminer le rayon d’une exoplanète. Le rayon d’une exoplanète dépend sur le rayon de l’étoile hôte qui est une fonction de ses propriétés chimiques! Pour réussir, Farbod utilise les données à haute résolution proviennent de l’instrument SPIROU qui est situé sur le télescope Canada-France-Hawaii.

Puis, Farbod utilise les techniques diverses de la spectroscopie chimique sur les données obtenues pour calculer les abondances chimiques des éléments différents dans l’atmosphère des naines étoiles de type spectral M. Cela est important pour comprendre l’évolution chimique de ces étoiles. En plus, cette étude va contribuer fortement à améliorer les modèles synthétiques stellaires qui existent.

Figure 5

Conferences and Carbon Footprints

By / par Sharon Morsink (University of Alberta)
(Cassiopeia – Summer / été 2020)

Authors: CASCA’s Sustainability Committee and Associates:
Sharon Morsink, Nicolas Cowan, Dennis Crabtree, Michael De Robertis, René Doyon, Vincent Henault-Brunet, Roland Kothes, David Lafrenière, Martine Lokken, Peter Martin, Christopher Matzner, Magdalen Normandeau, Nathalie Ouellette, Mubdi Rahman, Michael Reid, Joel Roediger, James Taylor, Robert Thacker, Marten van Kerkwijk

Canadians are responsible for CO2 emissions that are more than three times the annual global average of 4.8 tonnes per capita [1]. Most Canadian astronomers’ professional carbon footprint is dominated by air travel, and unlike telescope construction or rocket launches, flights — especially to conferences — are the immediate product of our individual choices. To reduce the environmental costs of our profession, we need real and desirable alternatives to jetting around to distant conferences.

Back in February, CASCA’s new Sustainability Committee was planning a virtual session for this year’s Annual General Meeting. But when the York meeting was cancelled due to the pandemic, an Online Organizing Committee was quickly assembled to plan a fully virtual conference. May’s online AGM, which was based around electronic posters and pre-recorded prize talks and community updates, drew 336 participants. We estimate that if everyone who participated from outside Ontario had flown in, the equivalent CO2 emissions would have been about 130 tonnes. (This may be an overestimate, as 43 respondents indicated on an exit survey that they would not have attended the in-person conference.)

The 2020 AGM was an interesting experiment, but how do we move forward? We aren’t advocating that all future conferences be completely virtual; we too would miss interacting with colleagues in person from time to time! Instead we would like to see the virtual options enhanced. We envision a future in which one would travel only to nearby conferences, and join remotely in most other cases. In the AGM exit survey (40% participation), about 60% of respondents reported missing the interactions that occur in person. Clearly, there is much work to be done to find effective and enjoyable ways to interact online with colleagues, but with improving text, video, and virtual reality options we believe this is possible. For instance, one could consider simultaneous physical meeting `hubs’ connected by a virtual link. Taking these points into consideration, the 2021 AGM organizers are already planning both in-person and remote ways to participate.

We encourage all astronomers to carefully consider how to minimize the impact of their research-related travel. In addition to being more selective about which conferences and meetings to attend in person, we recommend purchasing carbon offsets for those times when travel is needed. Not all institutions allow offsets to be reimbursed, and current NSERC spending rules for Discovery grants do not. Persistent advocacy is needed to change these policies, something which the Sustainability Committee will pursue. It is time for us to consider the environmental impact of our research, take stock of our own emissions, and plan a professional carbon budget in the same way that we plan a financial budget when managing our research grants.

[1] Hannah Ritchie and Max Roser (2017) – « CO₂ and Greenhouse Gas Emissions ». Published online at