Category BU news

Bishop’s student Sonoma Brawley awarded 3M National Student Fellowship

Sherbrooke – Bishop’s University student Sonoma Brawley is a recipient of the prestigious 3M National Student Fellowship (2024), the highest national recognition of student educational leadership in Canada.

The 3M National Student Fellowship recognizes up to ten full-time students per year at Canadian post-secondary institutions who have demonstrated outstanding leadership in their lives, at their post-secondary institution, and in their communities. These students embrace a vision of education that enhances their academic experience through leadership and community engagement.

Sonoma Brawley is a second-year student pursuing a BA in Music Performance with a Musical Theatre Concentration and English Minor at Bishop’s University. Originally from Squamish, BC, she is a Chancellor’s Excellence Scholar and recipient of Bishop’s Exceptional Student Talent (B.E.S.T.) Fund that supports innovative experiential learning opportunities. Sonoma is also a Stephen A. Jarislowsky Student Fellow, a three-term Humanities Senator for the Student Representative Council, Junior Co-Captain of the competitive dance team, and Co-Lead of the Bishop’s University Music Society.

Sonoma is being recognized for her transformative leadership as a research fellow for the Hope Circuits project, which seeks to re-wire universities for human flourishing, and for her contributions to the Online Learning Technology Consultant, a program that centers students in the design of 21st century classrooms.

In her dossier, Sonoma reflects on her journey as a student leader: “As a first-generation university student, the academic system seemed impenetrable and complex. Participating in the Hope Summits led by Dr. Jessica Riddell, my understanding of higher education frameworks expanded, and I realized that critical hope could rattle the cages to release new values and perspectives, and reinvent systems. Most importantly, I saw students as change agents and learners as hope in action. As a luminary, I hope to harness generativity to build meaningful change from the ground up by amplifying student voices.”

Sonoma Brawley joins a stellar group of Bishop’s students who have received this national recognition in recent years. Only ten fellowships are awarded each year from over 1.1 million eligible students attending Canadian post-secondary institutions, and Bishop’s has welcomed eight student fellows in the past nine years, including Liam O’Toole (2023), Sufia Langevin (2022) Georges-Philippe Gadoury-Sansfaçon (2021), Maxim Jacques (2020), Ethan Pohl (2019), Théo Soucy (2018) and Jason Earl (2015).

Dr. Jessica Riddell, 3M National Teaching Fellow and professor at Bishop’s University, nominated Sonoma for this award: “Sonoma is an exceptional student with a deep commitment to leadership, innovation, and advocacy, particularly in the field of humanities education. I have had the privilege of witnessing Sonoma’s transformative journey and contributions to our academic community at Bishop’s University and impact in the public sphere.”



Benjamin Tabah

for Sonia Patenaude

Communications Manager – Bishop’s University


Dr. Heather Lawford: 3M National Teaching Fellow

SHERBROOKE – Dr. Lawford, of Bishop’s University’s Department of Psychology, has been selected as one of this year’s ten 3M National Teaching Fellows.

Dr. Lawford is an award-winning educator, and her impact has been recognized with the highest honours of teaching at the university. She’s among the top ten changemakers in higher education. She is also a Canada Research Chair and one of the leading scholars on generativity, which is a field dedicated to how and why we create legacies in service of others.

“What an honour to receive the 3M National Teaching Fellowship and to join this community of transformative and creative professors! I am most grateful for the support of the Jarislowsky Chair and the mentoring network she created for stewarding this process,” notes Dr. Lawford.

“Bishop’s University is a place where we can be curious about teaching and research while also engaging in diverse communities both locally and farther afield. Ever since I arrived at Bishop’s in 2012, I have had the pleasure of learning from and with my students and youth across Canada.”

Dr. Lawford notes, “I’m committed to helping connect other faculty and administrators to authentically include student voice in decision-making, because when generativity spans from youth across adulthood, building generative spaces becomes even more collaborative. Part of my legacy work includes building supporting spaces within institutions that acknowledge youth generativity.”

In 2021 she received the William and Nancy Turner Teaching Award, the highest recognition at Bishop’s University. Her work has also been recognized by the Robert Gordon Educational Leadership Fund and the Student Representative Council (SRC) Social Sciences Division Teaching Award. For over 10 years she has worked with the Students Commission of Canada, a non-profit dedicated to amplifying youth voice and supporting their legacy work  She currently holds a Canada Research Chair in Youth Development Dr. Lawford has been awarded over $8 million in research funding from diverse granting agencies, including Tri-council, Public Safety Canada, and UNICEF for her work with young people, much of that funding going towards paying students and youth for their work. Her new book with Jessica Riddell, Unlocking Superhero Powers: Metaphors and Mentorship in the Marvel Cinematic Universe (forthcoming), helps readers unlock the qualities of generativity as superhero powers to make the world more equitable and just.

Dr. Jessica Riddell, also a 3M National Teaching Fellow (2015) and Jarislowsky Chair of Undergraduate Excellence at Bishop’s University nominated Dr. Lawford for this fellowship and says this: “Dr. Lawford extends learning beyond the classroom and into the world with student-led initiatives that empower students via conferences, summits, knowledge mobilization, co-chairing panels, leadership institutes – where her undergraduate students are authentically engaged as partners and colleagues, co-authors and co-inquirers. Dr. Lawford is a beloved and transformative educator.”



Benjamin Tabah

for Sonia Patenaude, Communications Manager

Bishop’s University


Ciné-vélo : a portrait of commuter cycling in Sherbrooke

Sherbrooke, April 24, 2024 – Cégep de Sherbrooke, Bishop’s University and Université de Sherbrooke come together for the third consecutive year to present Ciné-vélo on May 1st at La Maison du Cinéma in Sherbrooke.  This event, which launches Bike Month, aims to celebrate the many dimensions of cycling!

The event will begin with a 5@7 networking segment during which the documentary’s creators and members of the cycling community will present their research findings and projects throughout various kiosks in the outdoor space located behind La Maison du Cinéma.

At 7 p.m., Ciné-vélo will showcase a short film entitled Amours de vélo, with Laurent Ulrich, the film’s director in attendance. The feature screening event is Sherbrooke by Bike? A Portrait of Commuter Cycling in 2023 which presents the evolution of commuter cycling in the city of Sherbrooke. This project, spearheaded by director Johan Gass, is a co-creation of students from Cégep de Sherbrooke, Université de Sherbrooke, and Bishop’s University.

From the conception of the documentary to the soundtrack, graphic design, subtitles and much more, the creativity and commitment of the Sherbrooke college and university community will be in the spotlight!  This inter-establishment collaboration project is made possible thanks to the financial support of the Estrie Higher Education Hub (PRESE).

Audience members eager to continue the conversation following the screenings are invited to head to Siboire Dépôt in the evening. The event is free, and everyone is welcome, no reservation is required.

DATE: Wednesday, May 1, 2024

TIME: 5 p.m. to 7 p.m.: creators and members of the cycling community will present their research findings and projects at various kiosks in the space behind Maison du Cinéma in a 5@7 networking setting (cancelled in case of rain, follow details on the event’s Facebook page)

             7 p.m. to 8:30 p.m.: Screening in the most largest venue and free popcorn

LOCATION: La Maison du Cinéma, 65, King Street West, Sherbrooke (Quebec) J1H 1P1


– 30 –


Christine Tremblay, Communications Consultant

Direction des communications et des affaires corporatives | Cégep de Sherbrooke | 819 564-6350, extension 5155

Sonia Patenaude, Communications Manager

Communications Office | Bishop’s University | 819-822-9600, extension 2617

Isabelle Huard, Media Relations Consultant

Service des communications | Université de Sherbrooke | 819 821-8000, extension 63395

Major Improvements to Bishop’s University Main Vehicle Entrance

Sherbrooke, April 23, 2024 – Bishop’s University will begin renovations to its main entrance (Coulter Field entrance) as of May 1st to upgrade underground infrastructure networks. The addition of pedestrian walkways, new street lighting, the correction of a dip in the road which is covered during floods, and roadside tree planting are also planned to refurbish the area. Construction work is anticipated to be completed by mid-August 2024.

During construction, the main entrance (Coulter Field entrance) will be closed to all traffic. Students, faculty, staff and visitors of Bishop’s University and Champlain College arriving by car will be able access campus using the new East Entrance.

The project consists of replacing the waste pump station at Dewhurst Dining Hall to install a new gravity flow sewer line which will be built under the road from the main entrance to Dewhurst Dining Hall.

Excavation work between five and seven meters will be required to access the underground pipes. To ensure ongoing campus activities throughout the duration of the work, special measures are planned to reduce the quantity and duration of shutdowns for several services. Secure walkways will be installed to protect pedestrians. Safeguards will be put in place to protect nearby trees. However, the trees directly in the path of infrastructure work will either be relocated or cut down; this will be evaluated on a case-by-case basis. As always, trees that are cut down will be replaced on a ratio of 2 to 1 with new trees carefully selected to increase biodiversity in accordance with the latest Campus Master Plan.

Dewhurst Dining Hall and the John H. Price Sports and Recreation Centre will remain open throughout the summer.

The ‘P1’ parking lot near the John H. Price Sports and Recreation Centre will be closed for the duration of the construction work.



The construction project is largely located in Bishop’s main entrance. It is an opportunity to add various features recommended in the Campus Master Plan:

  • Carry out important infrastructure upgrades;
  • Integrate signature lighting across campus (from the main entrance to Paterson Residence and also leading to Dewhurst Dining Hall);
  • Improve the site’s main entrance;
  • Add plant cover to minimize the visual presence of vehicle traffic and parking;
  • Create a safer and comfortable pedestrian network;
  • Promote sustainable mobility and optimized waste management;
  • Encourage social interactions via pedestrian routes (crossings).



  • CAMPUS ACCESS: The new East entrance can be accessed via Route 108 from the West (Highway 410) or from the East. There is no double lane on Route 108 at the turn-off for the new entrance, please be vigilant.
  • EXITING THE CAMPUS: the right turn (to the East) towards Highway 410 is MANDATORY. No left turns are permitted. Motorists wishing to head towards the borough of Lennoxville (West) must go to the roundabout on Highway 410 and return West on Route 108.
  • The East entrance is prohibited for pedestrians and cyclists.
  • The lane is equipped with 4 speed bumps to encourage users to reduce their speed, especially when approaching the pedestrian crossing between the ‘P2’ parking lot and the back of the Sports Centre. The speed limit has been set at 30 km/h. The speed limit on campus is 20 km/h.
  • Built in a flood zone, the double track has a width of 6.6 meters, which is the maximum allowed. The profile of the track is a succession of tops and bottoms to ensure the flow of water through the chutes placed on each side of the track.
  • A pedestrian walkway linking parking lot ‘P2’ to parking lot ‘P1’ and/or Coulter Field has also been added behind the Sports Centre.



Sonia Patenaude, Communications Manager – Bishop’s University

819-342-2587 |

Bishop’s University Maintains Carbon Neutrality

Bishop's University campus

On Earth Day, Bishop’s University announces a reduction of its greenhouse gas emissions (GHGs) from owned and controlled sources, maintaining its carbon neutrality (for scopes 1 and 2) announced in April 2023. Carbon neutrality was attained before the University’s original goal of reaching this milestone by 2030.

“This further reduction in greenhouse gas emissions reflects the University’s ongoing commitment to environmental sustainability,” indicates Sébastien Lebel-Grenier, Principal and Vice-Chancellor of Bishop’s University. “It is important for us to demonstrate responsible environmental stewardship through the continued implementation of initiatives that positively impact our campus, the local community, and beyond.”

To offset its remaining GHG emissions, Bishop’s continues to purchase carbon reduction offset credits for projects in Quebec through Carbone Boréal (406 tons at a cost of $35 per ton) and through the Fundao-Santa Clara United Nations Carbon Offset platform in Brazil (1,216 tones at a cost of $3.70 per ton). This investment demonstrates Bishop’s commitment to environmental sustainability on a local and global scale.

Over the years, Bishop’s has undertaken numerous sustainability initiatives, including the implementation of the campus geothermal loop which has enabled Bishop’s to cease using heating oil, drastically reduce the consumption of natural gas and rely more on hydroelectricity for heating its buildings, students voting to ban the sale of single-use plastic water bottles on its campus in 2010, planting 10,500 trees on campus in 2021, and developing the Sustainable Agriculture and Food Systems program.

“While significant progress has been made, we acknowledge that more work remains in reducing other sources of greenhouse gas emissions, such as those associated with staff and student transportation,” notes Isabelle Goyette, Vice-Principal, Finance and Administration.

“Bishop’s plans to address remaining emissions through initiatives that favour public transit and by reducing waste. The University also notes the carbon sink effect of the standing forests on its 550-acre campus as well as the Johnville Bog and Forest Park it co-owns with the Université de Sherbrooke, although this beneficial effect is not applied to the current net zero emissions calculation.”



Sonia Patenaude
Manager of Communications

Researchers at Bishop’s University and University de Sherbrooke collaborate to grow CANberries

Sherbrooke, April 19th, 2024 – Dr. Mirella Aoun, from the Department of Environment, Agriculture and Geography and Dr. Sébastien Poncet of the Faculté de Génie de l’Université de Sherbrooke are collaborating to develop a method to extend the growing season of raspberries to meet demand regardless of climate conditions.

The research team from Bishop’s University and Université de Sherbrooke are benefiting from a $1M research grant through the Shepherd Phase of the Homegrown Innovation Challenge through the Weston Family Foundation. Should their work prove successful, the team can apply for an additional $5 million through the upcoming Scale Phase, which would allow the project to grow in scale through an additional $5 million in funding.

“At the heart of this competition lies the belief that the fusion of collaboration and broad expertise is the key to solving complex challenges in agriculture,” said Garfield Mitchell, Chair of the Weston Family Foundation. “Our grantees bring out-of-the-box, yet achievable, ideas to the table, and we are excited to see the innovations that arise from their shared passion and collaboration.”

Making raspberries grow outside their normal season will require Dr. Aoun’s extensive expertise in preconditioning and berry plant types and varieties to stagger production and techniques to “trick” the plants into “believing” it’s time to produce berries.

Woman standing in front of bushes of berries in a greenhouse.

“By capitalizing on the symbiotic relationship between research and teaching, and by leveraging our relationships within Bishop’s and the community, our researchers do world-class work in fields as diverse as astrophysics, digital indigeneity, and youth generativity”, indicates Dr. Kerry Hull, Dean of Sciences and Mathematics and Associate Vice-Principal Research at Bishop’s University.  “The CANberries project is a perfect example of this principle.   Thanks to the support of the Weston Family Foundation and the tireless work of Dr. Aoun, Bishop’s faculty, staff and students will be able to work alongside colleagues from the University of Sherbrooke to address the critical issue of food security.”

In collaboration with Dr. Leyla Amiri, Assistant professor in the Mechanical Engineering Department and Mr. Jean-François Lerat, Research and Development expert, Dr. Poncet will integrate Agrivoltaic and air technologies into a solar passive greenhouse (AARG) to control air, light, heat, and electric input management, as well as water treatment and irrigation to compensate for Canada’s low light and cold temperatures outside of natural berry production season.

If the researchers are successful, it could mean that raspberries could be produced sustainably to meet demand in Canada outside of the typical growing season, whether in urban or remote environments, and decrease reliance on imports.


CANberries is one of eleven projects funded by the Weston Family Foundation, as part of the Homegrown Innovation Challenge. Now entering the second phase of the Challenge, eleven Canadian teams have been awarded $1 million each to develop their bold ideas for extending the growing season of berries. Each team only has 18 months to build and test its proof-of-concept ideas before the next phase of the Challenge, which will see this group of eleven reduced to four teams. Learn more about the CANberries project here.


Delivered over six years, the $33 million Homegrown Innovation Challenge supports the development of tools and technologies to enable Canadian farmers and producers to grow berries out of season – sustainably and competitively. We believe that by accomplishing out-of-season berry production, we can unlock solutions for myriad other fruits and vegetables.


At the Weston Family Foundation (formerly The W. Garfield Weston Foundation), more than 60 years of philanthropy has taught us that there is a relationship between healthy landscapes and healthy people. That is why we champion world-class health research and innovation with the same passion that we support initiatives to protect and restore biodiversity on Canada’s unique landscapes. We take a collaborative approach to philanthropy, working alongside forward-thinking partners to advance Canada and create lasting impacts. We aspire to do more than provide funding; we want to enable others to find transformational ways to improve the well-being of Canadians.



Sonia Patenaude

Communications Manager – Bishop’s University

819-342-2587 |

BU Women’s Hockey Player Gabrielle Santerre makes U SPORTS History

Santerre becomes first player to hoist both U SPORTS Rookie of the Year and Player of the Year trophies in the same season


SASKATOON – Bishop’s Gaiters rookie sensation Gabrielle Santerre once again made history when she was named the U SPORTS Outstanding Player of the Year (Brodrick Trophy) and U SPORTS Rookie of the Year at the women’s hockey all-Canadian gala in Saskatoon on Wednesday.  It is the first time in any U SPORTS team sport that a player has won both accolades in the same season. This came three weeks after she was also the first player in the RSEQ to win both awards in the same year dating back to the inception of the U SPORTS National Championship in 1997-98.

Photo credit: University of Saskatchewan Athletics/U SPORTS 

Full story with highlights and photos: Santerre becomes first player to hoist both U SPORTS Rookie of the Year and Player of the Year trophies in the same season – Bishop’s University Athletics (

She was also named a first-team all-Canadian and member of the U SPORTS all-Rookie team.

Santerre, a Saint-Jean-sur-Richelieu, Que. native led the country in scoring with 45 points in 25 games. That was seven more than the next closest, her teammate Maude Pepin, who had 37, and nine up on UNB’s Lilian George who tallied 36 points in 28 games.

The 45 points is a modern-day RSEQ rookie record (dating back to 2007-08). It is the most scored in the conference since 2012-13 and most in the country since the 2013-14 campaign.

She was also part of the RSEQ’s first all-star team and all-rookie team. Additionally, she was named the RSEQ’s Athlete of the Month in November.

“What a year from Gab,” said Valerie Bois, Bishop’s Gaiters women’s hockey head coach.  “She is mature well beyond her years.  Her preparation and attention to detail is extraordinary.  She understands and continues to work hard to learn the system.  She loves talking hockey.  She has high standards but brings everyone with her.  She received a lot of accolades this year but has a team-first mentality.  We are extremely proud of her.”

A Sports Studies student, Santerre is no stranger to accolades – she was the Cegep Division 1 Player of the Year in her final two seasons with Champlain-Lennoxville.

She helped lead the Bishop’s Gaiters to their best-ever season in 2023-24 with 32 points and a second-place finish in the RSEQ.

Follow the Bishop’s Gaiters on Instagram @GaitersWHK and @BishopsGaiters and stay up-to-date with everything Bishop’s Gaiters at



Marty Rourke





819-822-9600 x 2507


Experience the Solar Eclipse at Bishop’s University

A total solar eclipse will be visible on the afternoon of April 8, 2024, and the Bishop’s University campus is directly in the path of totality. Bishop’s University invites the community to a series of activities around Coulter Field to offer a memorable eclipse-viewing experience in the region.

Total solar eclipses are a rare once-in-a-lifetime phenomenon, when day briefly turns into night as the Moon completely blocks the Sun. This is such a rare occurrence that the next total solar eclipse to be visible in a large city in the province will be in… 2106!  The partial eclipse will begin at about 2:16 p.m. and end at about 4:38 p.m., with “totality” occurring at about 3:26 p.m. and lasting for 3 minutes and 26 seconds.


Eclipse Glasses

Bishop’s will be providing glasses free of charge for registered guests to our on-campus eclipse viewing event! Members of the Bishop’s community and visitors will gather on Coulter Field to experience this unique event. Visitors are invited to explore the various kiosks where they will find information about physics, astronomy, and detailed eclipse information. Student volunteers will guide visitors on campus tours.

As parking will be limited on campus, eclipse-viewers are strongly encouraged to walk to campus to avoid traffic getting on and off campus.


Donald Lecture Series – Fantastic Eclipses, From Fear to Reason

Ahead of the total solar eclipse on April 8, join us for a talk by astronomer Jean-Louis Heudier on Thursday, April 4th at 7 p.m. at Centennial Theatre. Dr. Heudier is an internationally respected astronomer and author of Astronomical Photography, Eclipses of the Moon and Sun, Book of the Sky, Book of the Moon, and Astronomy for All. This free event is presented as part of the Donald Lecture Series.

More activities will be announced soon. Visit the Eclipse-viewing at Bishop’s web page for regular updates and for advice on how to watch the eclipse safely.

For further information regarding the eclipse-viewing event on the campus of Bishop’s University, please send a message to



Sonia Patenaude, Manager of Communications | 819-342-2587

Bishop’s University Forges Strategic Partnership with Desjardins Group – Enhancing initiatives focused on the student community

Bishop’s University is thrilled to announce a transformative partnership with Desjardins aimed at supporting four key initiatives benefiting students over the next three years. Desjardins has pledged a generous donation of $310,000, reinforcing its commitment to education and community development.

Financial leverage to support innovative solutions

Estrie-Preneur ($170,000)
Under the leadership of Vincent Cloutier, this initiative will pair students with local entrepreneurs for a two-month immersive experience. Through full-time collaboration, students will gain valuable hands-on experience in the business world, fostering a deeper understanding of real-world challenges and opportunities.

Desjardins Exam Care Packages ($60,000)
With a focus on promoting a healthy lifestyle, these care packages aim to support students during the stressful exam period. The initiative underscores the importance of well-being during challenging times and reflects the supportive spirit of the community.

Scholarships ($50,000)
These bursaries, ranging from $2,500 to $5,000, aim to alleviate the financial burden on students pursuing excellence in their academic endeavors.

Desjardins Pitch Competition ($30,000)
Integrated into select courses offered by the Williams School of Business (WSB), this competition challenges students to create startup companies and present comprehensive business plans to a panel of judges. The top three teams will be rewarded with monetary prizes, encouraging creativity, and building students’ confidence in entrepreneurship.

Dr. Sébastien Lebel-Grenier, Principal and Vice-Chancellor of Bishop’s University, expressed gratitude for Desjardins’ commitment to education, stating, “This partnership contributes significantly to empowering our students, promoting excellence and fostering a vibrant, supportive learning community.”

“As we renew our partnership, Desjardins Group is proud to continue enriching the lives of students at Bishop’s University,” said Isabelle Garon, Executive Vice-President, Marketing, Communications, Cooperation and President’s Office. “Giving young people the resources and support they need for their professional development is essential, and I believe that these four initiatives will play a key role.”

“I am very happy to be one of this year’s recipients of the Desjardins Bursaries, and I am very appreciative of Desjardins’ generosity and support towards my future as I continue furthering my education,” declared Courtney Gallan, second-year student in the School of Education at Bishop’s University.

Ms. Jacqueline Scott, Associate Vice-Principal, Alumni Relations and Philanthropy, highlighted the impact of these initiatives on student well-being, saying, “The Exam Care Packages and Scholarships will make a tangible difference in the lives of our students, supporting both their academic and personal journeys.”

The collaboration between Bishop’s University and Desjardins exemplifies a shared vision for the advancement of education, entrepreneurship, and student success. The combined efforts will undoubtedly contribute to the growth and development of the Bishop’s University community.

About Desjardins Group
Desjardins Group is the largest financial cooperative in North America and the fifth largest in the world, with assets of $414.1 billion as of September 30, 2023. Desjardins was named among the world’s best employers for women according to Forbes magazine. To meet the diverse needs of its members and customers, both individuals and businesses, it offers a complete range of products and services through its vast network of service points, its virtual platforms and its subsidiaries present throughout Canada. Ranked among the strongest banking institutions in the world according to The Banker magazine, Desjardins boasts capital ratios and credit ratings that are among the best in the industry.



Sonia Patenaude
Communications Manager – Bishop’s University
819-342-2587 |

Information (for media only):
Jérémi Trudel
Public Relations Desjardins Group
514-281-7000, extension 5553436

Secrets of a Hot Saturn and its Spotted Star Unlocked – Dr. Jason Rowe, study co-investigator

A team of astronomers, including Dr. Jason Rowe of Bishop’s University, has unraveled the enigmatic atmosphere of the exoplanet HAT-P-18 b, shedding light on its intriguing blend of gases, clouds, and even the effects of its star’s activity. Leveraging the James Webb Space Telescope (JWST) and sophisticated modelling techniques, their pioneering study provides a remarkable peek into the complexities of distant worlds and paves the way for a deeper understanding of exoplanetary atmospheres and the importance of considering their stars.

An artistic representation of the “hot Saturn” exoplanet, HAT-P-18 b. (Credit: NASA/Eyes on Exoplanets)


Exoplanets, planets located beyond our Solar System, captivate both scientists and the public, holding the promise of unveiling diverse planetary systems and potentially habitable worlds. Despite being very much not like our Earth, large gas giant planets found very close to their stars have proven to be ideal test targets for telescopes like the James Webb Space Telescope (JWST) to refine astronomers’ methods of understanding exoplanets. One such planet is HAT-P-18 b, a “hot Saturn” type planet located over 500 light-years away with a mass similar to Saturn’s but a size closer to that of the larger Jupiter. This gives the exoplanet a puffed-up atmosphere that is especially ideal for analysis.

Led by a team of researchers from the Trottier Institute for Research on Exoplanets at the Université de Montréal (UdeM), a team of astronomers, including Dr. Jason Rowe, Canada Research Chair in Exoplanet Astrophysics, and professor in the department of Physics and Astronomy, harnessed the power of the revolutionary Webb Telescope to study HAT-P-18 b. Their findings, detailed in the journal Monthly Notices of the Royal Astronomical Society (MNRAS), provide a comprehensive portrait of the hot Saturn’s atmosphere while delving into the complexities of distinguishing atmospheric signals from stellar activity.


Passing over a spotted star

Observations from the Webb Telescope were taken while the exoplanet HAT-P-18 b was passing in front of its Sun-like star. This moment is called a transit and is crucial to detect and further characterize an exoplanet from hundreds of light-years away with surprising precision. Astronomers are not observing light that is being emitted directly by the distant planet. Rather, they are studying how the central star’s light is being blocked and affected by the planet orbiting it.

The light curve shows the luminosity or brightness of the star over time. When the exoplanet passes over the star, known as a transit, part of the star’s light is blocked by the exoplanet. As a result, the star’s luminosity decreases. When a star spot is occulted on the star’s surface, or when the exoplanet passes over the dark spot, astronomers can see a signal in the light curve in the form of a small bump in the bottom of the transit light curve. See the full animation of this infographic here. (Credit: B. Gougeon/Université de Montréal)

Exoplanet hunters must thus grapple with the challenge of disentangling signals caused by the presence of the planet and those caused by the star’s own properties. Just like our Sun, stars do not have uniform surfaces. They can have dark star spots and bright regions, which can create signals that mimic a planet’s atmospheric attributes. A recent study of the exoplanet TRAPPIST-1 b and its star TRAPPIST-1 led by UdeM Ph.D. student Olivia Lim witnessed an eruption, or flare, on the surface of the star, which affected their observations.

In the case of planet HAT-P-18 b, Webb caught the exoplanet right as it was passing over a dark spot on its star, HAT-P-18. This is called a spot-crossing event, and its effect was evident in the data collected for the study. The team also reported the presence of numerous other star spots on HAT-P-18’s surface which were not blocked out by the exoplanet. To accurately determine the exoplanet’s atmospheric composition, the researchers determined it was necessary to simultaneously model the planetary atmosphere as well as the star’s peculiarities. They state that such consideration will be crucial in treating future exoplanet observations from the JWST to fully harness their potential.

“The lesson we have learned from observing Hat-P18-b is ‘know-thy-star-know-thy-planet’.”, states Dr. Jason Rowe, a co-investigator of the study.  “We learn the characteristics of exoplanets by observing their shadow as they transit their host star. If the star is changing its appearance, those changes will be reflected in observed properties of the exoplanet transit.  A better understanding of stellar astrophysics with unprecedented observations from JWST allowed the team to distinguish between the effects of star spots and exoplanet atmosphere abundances. ”


H2O, CO2, and clouds in a scorching atmosphere

Following their careful modelling of both the exoplanet and the star in the HAT-P-18 system, the team of astronomers then performed a meticulous dissection of HAT-P-18 b’s atmospheric composition. By inspecting the light that filters through the exoplanet’s atmosphere as it transits its host star, the researchers discerned the presence of water vapour (H2O) and carbon dioxide (CO2). The researchers also detected the possible presence of sodium. Adding intrigue to the findings, the team observed strong signs of a cloud deck in HAT-P-18 b’s atmosphere, which appears to be muting the signals of many of the molecules found within it. They also concluded that the star’s surface was covered by many dark spots that can significantly influence the interpretation of the data.

While molecules like water, carbon dioxide, and methane can be interpreted as biosignatures, or signs of life, in certain ratios or in combination with other molecules, HAT-P-18 b’s scorching temperatures of close to 600 degrees Celsius do not bode well for the planet’s habitability.

The data used from the JWST in this study were collected by the Canadian-made NIRISS (Near-Infrared Imager and Slitless Spectrograph) instrument, which has provided astronomers with the unparalleled ability to differentiate many of HAT-P-18 b’s atmospheric characteristics from one another. The results show that observations taken on the far-visible to near-infrared within the NIRISS instrument’s wavelength range are essential to disentangle the signals from the planetary atmosphere and the star. Future observations from another JWST instrument, the Near Infrared Spectrograph (NIRSpec), would help refine the team’s results, such as the CO2 detection, and shed even more light on the intricacies of this hot Saturn exoplanet.


About this study

The paper “Near-Infrared Transmission Spectroscopy of HAT-P-18 b with NIRISS: Disentangling Planetary and Stellar Features in the Era of JWST” was published in Monthly Notices of the Royal Astronomical Society on December 9, 2023. The lead authors are Marylou Fournier Tondreau, previously an M.Sc. student at the Trottier Institute for Research on Exoplanets at the Université de Montréal (UdeM) and now a Ph.D. student at the University of Oxford, Ryan J. MacDonald, Fellow at the University of Michigan, and Michael Radica, Ph.D. student at UdeM. Other iREx researchers that contributed to this paper are David Lafrenière (UdeM), Caroline Piaulet (UdeM), Louis-Philippe Coulombe (UdeM), Romain Allart (UdeM), Kim Morel (UdeM), Étienne Artigau (UdeM), Loïc Albert (UdeM), Olivia Lim (UdeM), René Doyon (UdeM),  Björn Benneke (UdeM), Jason Rowe (Bishop’s U), Antoine Darveau-Bernier (UdeM), Nicolas Cowan (McGill), Neil Cook (UdeM), Frédéric Genest (UdeM), Stefan Pelletier (UdeM), Lisa Dang (UdeM), and Jake Taylor (UdeM and the University of Oxford). Additional contributors are based out of the Arizona State University, Cornell University, the University of Victoria, and the National Research Council of Canada’s Herzberg Astronomy and Astrophysics Research Centre.


For more information

MNRAS scientific paper

arXiv scientific paper





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