Graduate Student Highlights

By Carter Rhea (Chair, CASCA Graduate Student Committee)
(Cassiopeia – Winter / hivers 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 several students from around the country. In this issue, we share the highlights of new students since the last issue of Cassiopeia.

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

Mainak Singha — University of Manitoba

Mainak’s research investigates how weakly accreting ‘Active Galactic Nuclei’ (AGN) can drive galaxy evolution processes. Most successful galaxy evolution models require the AGN to launch galactic scale outflows to drive the galaxy evolution processes. In order to trace the signs of outflows, he uses spectroscopic data (spectra) from SDSS (Sloan Digital Sky Survey). The emission lines from these spectra pin-point the evidences of ionization caused by the photons from the AGN accretion disks or the shocks from the AGN. Any asymmetry in the emission line profiles indicates the gas moving towards / moving away from us which are the signatures of outflows.

Figure 1


Figure 1 is a standard BPT diagram from SDSS DR7. The radio galaxy J142041+025930 lies in the LINER (Low Ionization Nuclear Emission Line Region) region suggesting it to be a Low Excitation radio galaxy (LERG).

Vivian Tan — York University

Vivian’s research is on the galaxies that reside within massive clusters at redshifts 0.25 < z < 0.6, in the Hubble Frontier Fields. Clusters are dynamic environments where galaxies interact and quench, which means transitioning from star-forming to quiescent. Quenching processes alter a galaxy’s morphology, which we want to measure not just with their light profiles but through their stellar mass distribution. Mapping where the stellar mass is in a galaxy is usually difficult at z > 0, but the Frontier Fields have deep multiband Hubble photometry. This means resolved stellar mass maps are possible even for galaxies as small as 108 solar masses. Galaxies with such low stellar masses have not been studied in a resolved way at z > 0. Because we can analyze morphology with resolved stellar mass maps, we found that quiescent galaxies which are less massive than 109.5 solar masses are more likely to be disk-dominated (Sersic index ~ 1 to 2), but quiescent galaxies are bulge-dominated above that mass limit (Sersic index of 4 or more). This was only found in clusters but not in the less dense “field” environments. This means different quenching processes must have occurred to transform these galaxies, and these quenching processes depend both on the galaxy’s mass and their environment.

Figure 2


Figure 2 shows the process of creating the resolved stellar mass maps through a process called SED-fitting. The galaxy is broken up into spatial bins, and a SED is fitted to photometric flux from multiple bands in each of the bins. The fitted SED can reveal what the stellar mass of that region of the galaxy is and putting it all together results in a resolved stellar mass map. Sersic index measurements for the stellar mass are obtained via parametrically fitting a 2-D Sersic profile directly to the map of stellar mass using GALFIT.

Jessica Campbell — University of Toronto

Jessica’s research focuses on the multiphase nature of our Galaxy’s magnetic field and how it connects between different phases of the interstellar medium (ISM). Whether it is the turbulent warm ionized medium (WIM) that fills much of the Galaxy or the cold neutral medium (CNM) often found in sheets and filaments, this complex ISM is permeated with high energy cosmic rays and magnetic fields. When accelerated by the magnetic field, these cosmic rays emit radio synchrotron radiation that is strongly linearly polarized. As this polarized emission passes through the foreground ISM, thermal electrons and magnetic fields in the WIM rotate the plane of polarization, an effect called Faraday rotation. These cosmic rays can also penetrate and ionize the densest regions of the ISM, causing even the predominantly neutral medium to be coupled to the magnetic field via linear 21 cm HI structures called ‘HI fibers.’ Despite the wealth of magnetic field information about the WIM and CNM, very little is known about how they relate to one another. Do the diffuse ionized and cold clumpy media share a common magnetic field? If so, how often does this occur, and under what circumstances? These are the questions driving Jessica’s research.

Figure 3


Figure 3 shows Planck dust emission at 353 GHz, where the coloured image is the total (unpolarized) intensity and the textured lines indicate the magnetic field orientation. The dust emission clearly contains the same knee and fork morphologies, and the overall field orientation is roughly parallel to the polarized filaments F1 and F3.

Robert Bickley — University of Victoria

Robert’s research focuses on the intersection between observational astronomy and machine learning, specifically, using machine vision techniques to identify galaxies that have recently undergone a merger with another galaxy. Mergers often leave behind a distinct visual signature, giving rise to unusual morphologies and leaving behind displaced streams of stars. To identify mergers using machine vision, he trains Convolutional Neural Networks (CNNs) on examples of mergers and non-mergers taken from a simulation (IllustrisTNG) and modified to look like real observations. He can then use the simulation data to identify where the CNNs are successful, and where they struggle.

Figure 4


Figure 4 shows how well a CNN identifies mergers and non-mergers as a function of the environment. If a galaxy has a neighbor very close by, it will have a small r_1 value. If there are no nearby neighbors, r_1 will be very large. The top panel shows the total number of post-mergers and controls (blue and orange histograms, respectively), further broken down as correctly and incorrectly classified (fp, brown: controls classified as post- mergers; tn, purple: correctly-classified controls; fn, red: post-mergers classified as controls; tp, green: correctly-classified post-mergers). The bottom panel shows the fraction of post-merger and control galaxy images correctly identified by the model.

The figure demonstrates that the model retains much of its ability to distinguish between mergers and non-mergers with a close neighbor down to 10 kiloparsecs, below which the visual degeneracy becomes prohibitive. However, such close neighbors are rare in both the simulation and the real Universe, and therefore do not present a significant source of contamination.

Long Range Plan 2020

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

On behalf of Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David Lafrenière, Brenda Matthews and Alice Shapley, we are pleased to present the final report of CASCA’s 2020 Long Range Plan for Canadian Astronomy (LRP2020). The unformatted version of the report is now available on the CASCA website. A professionally-designed version and a French translation are in progress and are expected to be available early in 2021.

We thank everyone who contributed to the LRP process by writing a white paper, attending a town hall, participating in consultations, or answering our many requests for information. We would especially like to recognize the very hard work of the LRP2020 panel members over the past twenty months. We are also grateful to the agencies whose financial support enabled the LRP2020 process, and to the CASCA Board for entrusting us with the leadership of this exercise.

This will be our last Cassiopeia update. The LRP2020 section on the CASCA website contains links to all of the submitted white papers and reports as well as a summary of the process. The designed and translated versions of the report will be available there once complete.

chairs@lrp2020.groups.io

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.

CATAC Update on the Thirty Meter Telescope

By Michael Balogh (CATAC Chair)
(Cassiopeia – Winter 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.

LRP2020 Final Report

Dear Colleagues:

On behalf of Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David  Lafrenière, Brenda Matthews and Alice Shapley, we are pleased to  present the final report of the CASCA 2020 Long Range Plan for  Canadian Astronomy (LRP2020).  The unformatted version of the report  is now available on the CASCA website at  https://casca.ca/wp-content/uploads/2020/12/LRP2020_December2020-1.pdf. A  professionally-designed version and a French translation are in  progress and are expected to be available early in 2021.

We thank everyone who contributed to the LRP process by writing a  white paper, attending a town hall, participating in consultations, or  answering our many requests for information. We would especially like  to recognize the very hard work of the LRP2020 panel members over the  past twenty months.

The LRP2020 section on the CASCA website (https://casca.ca/lrp2020)  contains links to all of the submitted white papers and reports as  well as a summary of the process. The designed and translated versions  of the report will be available there once complete.

Pauline Barmby & Bryan Gaensler
LRP2020 Co-Chairs
chairs@lrp2020.groups.io

LRP2020 final report

Dear colleagues,

On behalf of Matt Dobbs, Jeremy Heyl, Natasha Ivanova, David Lafrenière, Brenda Matthews and Alice Shapley, we are pleased to present the final report of the CASCA 2020 Long Range Plan for Canadian Astronomy (LRP2020). The unformatted version of the report is now available on the CASCA website. A professionally-designed version and a French translation are in progress and are expected to be available early in 2021.

We thank everyone who contributed to the LRP process by writing a white paper, attending a town hall, participating in consultations, or answering our many requests for information. We would especially like to recognize the very hard work of the LRP2020 panel members over the past twenty months.
The LRP2020 section on the CASCA website contains links to all of the submitted white papers and reports as well as a summary of the process. The designed and translated versions of the report will be available there once complete.

Pauline Barmby & Bryan Gaensler
LRP2020 Co-Chairs
chairs@lrp2020.groups.io

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, mbalogh@uwaterloo.ca
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)

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 (https://globalnews.ca/news/7180914/canada-race-based-data-covid-19/).
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.

References

  1. https://www.particlesforjustice.org/letter
  2. https://arxiv.org/abs/1910.01272
  3. https://www.un.org/development/desa/indigenouspeoples/climate-change.html
  4. https://www.nytimes.com/interactive/2020/08/06/climate/climate-change-inequality-heat.html
  5. https://www.nytimes.com/interactive/2019/08/06/climate/world-water-stress.html?action=click&module=News&pgtype=Homepage
  6. https://features.propublica.org/climate-migration/model-how-climate-refugees-move-across-continents/
  7. https://www.nytimes.com/2018/03/12/climate/kenya-drought.html
  8. https://advances.sciencemag.org/content/6/19/eaaw1838
  9. https://www.nature.com/articles/d41586-020-00164-8
  10. https://www.theguardian.com/environment/2020/jul/17/dramatic-footage-fuels-fears-amazon-fires-could-be-worse-than-last-year
  11. https://www.cbsnews.com/news/wildfires-sibera-russia-burned-area-larger-than-greece-heat-wave/
  12. https://www.nytimes.com/2020/07/30/climate/bangladesh-floods.html
  13. https://www.un.org/en/chronicle/article/small-islands-rising-seas
  14. https://www.nytimes.com/interactive/2020/02/13/climate/manila-san-francisco-sea-level-rise.html
  15. https://ourworldindata.org/per-capita-co2
  16. https://www.ubcpress.ca/asset/9296/1/9780774821018.pdf
  17. http://fnn.criaw-icref.ca/images/userfiles/files/LWM3_ColonialismImpacts.pdf
  18. https://www.nrcan.gc.ca/science-data/data-analysis/energy-data-analysis/energy-facts/crude-oil-facts/20064
  19. https://ourworldindata.org/per-capita-co2
  20. https://bifrostonline.org/how-is-climate-change-impacting-indigenous-communities-in-remote-regions-of-canada/
  21. https://www.theguardian.com/world/2018/may/30/canada-inuits-climate-change-impact-global-warming-melting-ice
  22. https://www.climatechangenews.com/2019/11/28/indigenous-communities-forefront-climate-resilience/
  23. https://www.cbc.ca/news/indigenous/pictou-landing-first-nation-northern-pulp-1.5447179
  24. https://www.canada.ca/en/services/health/publications/healthy-living/reducing-urban-heat-islands-protect-health-canada.html
  25. https://www.canada.ca/content/dam/esdc-edsc/migration/documents/eng/communities/reports/poverty_profile/snapshot.pdf
  26. https://www.nytimes.com/interactive/2019/08/09/climate/city-heat-islands.html
  27. https://www.theguardian.com/society/2020/jan/13/racist-housing-policies-us-deadly-heatwaves-exposure-study
  28. https://ecojustice.ca/exposing-canadas-toxic-secret/
  29. https://humanrights.ca/story/the-story-of-africville
  30. https://science.sciencemag.org/content/early/2020/08/12/science.aay4497/tab-pdf
  31. https://www.cbc.ca/news/canada/thunder-bay/grassy-narrows-framework-1.5520501
  32. https://www.nytimes.com/2020/06/18/climate/climate-change-pregnancy-study.html
  33. https://www.vox.com/the-big-idea/2017/12/12/16766872/overpopulation-exaggerated-concern-climate-change-world-population
  34. Rosling, H., Rosling Rönnlund, A. and Rosling, O., 2019. Factfulness. Paris: Flammarion.
  35. https://www.theguardian.com/world/2019/jan/27/what-goes-up-population-crisis-wrong-fertility-rates-decline
  36. https://www.nhpr.org/post/outsidein-problem-concerns-about-over-population-part-one#stream/0
  37. https://www.newyorker.com/news/news-desk/environmentalisms-racist-history
  38. https://academic.oup.com/bioscience/article/67/12/1026/4605229
  39. https://www.nrdc.org/stories/environmental-justice-movement
  40. https://rabble.ca/blogs/bloggers/making-waves/2018/11/six-nations-youth-leads-protest-against-nestl%C3%A9-water-operation

Graduate Student Highlights

By Carter Rhea (Chair, CASCA Graduate Student Committee)
(Cassiopeia – Summer 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

Solar flares are sudden and intense releases of magnetic energy stored in the corona, causing the plasma to heat up to 10 million degrees Kelvin. The radiation and highly energetic particles emitted from these events can damage our satellite communication network and pose a health threat to astronauts. It has been suggested since the early 1990s, by E.T. Lu and collaborators, that solar flares are a manifestation of unobservable small scale magnetic reconnection processes that can be simulated by simple lattice models, called “avalanche models”. The goal of my master’s research project is to evaluate the predictive capabilities of these models in making solar flare forecasting. We first studied the stochastic behaviour of many avalanche models, and now are integrating data assimilation using X-ray observations of flares to improve our prediction methods.

Figure 1 – Cartoon of a physical interpretation of a coronal loop accumulating energy through the twisting of its footprints. (Strugarek et al. 2014)

Mallory Thorp — University of Victoria

Mallory’s research investigates how galaxies change as the result of a major galaxy merger, when two galaxies of comparable size interact and merge to form a single galaxy. To understand the kpc-scale changes resulting from a merger event, she uses Integral Field Spectroscopy (IFS) measurements from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. IFS provides a spectrum for every pixel on an image of a galaxy, allowing her to examine how spectral dataproducts like star-formation rate (SFR) vary across a galaxy.

Figure 2 contains 3 examples of post-merger galaxies from MaNGA (1st column), along with maps of their SFR surface density (2nd column). By comparing the maps of SFR from post-merger galaxies to those of isolated galaxies, she can quantify the change in SFR as the result of the merger event.

The 3rd column shows enhancements in SFR as a result of the merger in blue, whereas a deficit in SFR compared to an isolated galaxy are shown in red. On average post-mergers experience a galaxy-wide enhancement in SFR, like the 2nd and 3rd post-mergers. Variations from this, like the notable suppression of SFR in the outer regions of 1st post-merger, could indicate different progenitor qualities and orientations can alter how effectively star-formation is enhanced.

This work was completed by myself, under the supervision of Sara Ellison (both of us CASCA members!).

Figure 2

Lingjian Chen — Saint Mary’s University

My research is a galactic environment study. Dense galactic environments, such as galaxy groups and clusters, are thought to be formed through hierarchical mergers. Spatial distribution of satellite galaxies can be a good indicator for galaxy evolution in such environments.

We study the radial distribution of satellites around isolated massive central galaxies using data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (HSC-SSP) and the CFHT Large Area U-band Deep Survey (CLAUDS). Thanks to the large area, 6-band photometry and good depth of the combined survey, we were able to identify ~5000 centrals in a redshift range of 0.3<z<0.9 and also identify satellites around them down to stellar mass of 109.5 solar mass.

Our results show that satellite number density distribution can be described by an NFW profile (Navarro+1995, usually for mass density profile in dark matter halos) on scales greater than 100 kpc but deviates from it within that scale. This feature is seen out to z=0.9, it was previously found in studies at low redshift (e.g. Tal+2012). We have also investigated the dependence of the distribution on satellite and central properties such as mass and star-forming level. We concluded that the mechanism of shaping satellite distribution can probably be related to a combination of dynamic friction and tidal stripping when they are orbiting in the dark matter halo, but more detailed simulation or modelling are needed to understand better the physical process.

Figure 3 shows our satellite galaxy selection. Central galaxy is indicated by the yellow circle, potential satellites are circled in green, and red circle indicates our selection radius for satellites (700 kpc). Central galaxies were identified by mass and isolation criteria. Satellites were selected by photo-z difference and a circular aperture (basically a cylindrical selection centred on central galaxy). Number of satellites selected here were then corrected for contaminating background objects.

Figure 3

Figure 4 shows surface number density of satellite galaxies (averaged) around one central galaxy, after correction for background objects. The solid line is the best fit curve and can be separated into NFW component on large scale and Sersic component on small scale (dotted and dashed lines).

Figure 4

Farbod Jahandar — L’Université de Montréal

The main quest of Farbod’s work is unravelling the chemistry of our nearest stellar neighbours. This includes high-resolution observation and examination of M dwarfs as the most numerous type of star in our Galaxy and the smallest and coolest kind of star on the main sequence. Such an analysis impacts many fields of astrophysics, in particular, the determination of exoplanet radius that depends on a reliable estimate of the host radius that in turn depends on its chemical characteristics.

To achieve this goal, Farbod uses high-resolution data from the SPIRou instrument, which is one of the world-leading instruments at the Canada-France-Hawaii telescope. Then he uses chemical spectroscopy methods on the obtained data for the determination of the chemical abundance of different elements in the outer atmosphere of M dwarfs. This will be a critical component for a better understanding of the chemical evolution of M dwarfs and also can heavily contribute to chemical and dynamical improvements of the current synthetic stellar models.

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 OurWorldInData.org.