Alexandrine L’Heureux at the Pan-African School for Emerging Astronomers (PASEA)

The Pan-African School for Emerging Astronomers (PASEA) took place from September 2 to 6 in Monastir, Tunisia. Held every two years, PASEA is a summer school for university students and teachers across Africa with a marked interest in astronomy. The program is organized and taught by an African-led international collaboration with the main objectives of building a critical mass of astronomers in Africa and exchanging ideas about teaching.

Alexandrine L’Heureux, PhD student at IREx, joined the instructor team for the 2024 edition of PASEA. She shares her experience here.

PASEA 2024

Participants in front of the Palais des Sciences in Monastir, Tunisia. Credits: Saadi Kaoutar

For the first time since its inception in 2013, PASEA was held in North Africa. Over forty students and teachers from Tunisia, Morocco, Algeria, Libya, Egypt and Niger gathered together at the Monastir Science Palace in Tunisia. Participants were divided into two learning streams according to their level of prior knowledge. I was an instructor in the “undergraduate” stream, which introduces students to the scientific method and the main areas of astronomy. A stream is also offered to “graduate“ students in which they learn concrete methods of analysis through programming.

Inquiry-based learning

Students investigating how to measure the distance to the study balloon. Credits: Alexandrine L’Heureux

One of the key features of the PASEA program is its hands-on pedagogical approach. Rather than taking a conventional approach to teaching, such as a traditional lecture format, instructors encourage students to ask their own questions and define their own path to understanding. This conceptual approach was introduced on the very first day, when students had to discover for themselves the method used by astronomers to determine the distance to various objects in space, such as stars. This is what is known in astronomy as the cosmic distance ladder. Since all astronomical research relies on our knowledge of the distance to the object or phenomenon under study, this is a very fundamental method. The students were then able to apply it to a small research project on a topic of their choice. As an instructor, my role was to supervise the working groups, suggesting avenues for reflection and guiding their reasoning. A participant said, after the program : “I was really impressed that I learned how to discover things the way scientists do.”

Inquiry-based learning was warmly embraced by participants, saying it has enriched their understanding and consolidated their knowledge. Solving complex problems has the added benefit of strengthening their scientific identity. 

An introduction to exoplanets and the James Webb Space Telescope (JWST)

PASEA programming also includes several presentations on the various fields of astronomy: stars, cosmology, radio astronomy, galaxies and exoplanets. To engage students, these learning components are punctuated by questions and discussions. 

Animation by Alexandre l’Heureux on exoplanets. Credits: Jielai Zhang

The presentation on galaxies was delivered virtually by our colleague Heidi White, a co-founder of PASEA and a long-time PASEA instructor. Students were introduced to the different visual and physical characteristics of galaxies and the importance of the James Webb Space Telescope (JWST) in understanding their formation and evolution. After the lecture, participants constructed a paper model of JWST to familiarize themselves with the telescope’s various components and their respective functions.

Given my scientific expertise, my main task was to design and lead the lecture and activity sessions on exoplanets. I introduced the concept of exoplanets by presenting the main detection methods that enable us to discover and characterize these planets outside the Solar System. Some outstanding examples of exoplanet discoveries, such as WASP-76 b and LHS 1140 b, were also discussed. Students were particularly surprised by the extreme climates of hot Jupiters, gas giant planets that orbit their star in just a few days. I was happy to read the testimony of a participant: “I loved the exoplanets lecture because the vocabulary was easy to understand and the instructor presented well”. 

PASEA participants then put their new knowledge into practice by working in small groups to select an exoplanet they would like to study with JWST. Following the “In an Astronomer’s Shoes” activity from Exoplanets in the Classroom, the students wrote a telescope observing proposal to justify why their chosen exoplanet would make a compelling target for follow-up observations with JWST. After each team presented their arguments, a vote determined which proposal would be allocated observing time, a process similar to that employed by astronomical observatories around the world.

Final reflections

Taking part in PASEA was an absolutely extraordinary experience, but not without its challenges. I had never actively taken part in an operation of this magnitude, let alone outside of Québec. I had to prepare my material meticulously, while being ready to improvise in case of unforeseen circumstances. Language, for example, was one of PASEA 2024’s biggest challenges, as English was the third or even fourth language of a significant proportion of the participants. As a result, we had to quickly restructure the schedule to leave time for translations. My knowledge of French proved particularly useful in helping groups less comfortable in English.

The students all inspired me with their motivation, curiosity and enthusiasm. I also got to know an incredible team of committed and passionate science educators. By working alongside them, I was able to learn from their experience while contributing to the success of the program by sharing my own skills and resources.