This summer, a team of undergraduate students from U of T Engineering launched an experiment into the stratosphere that could help scientists better understand the health risks posed by human space travel.
Katarina Poffley (Year 4 EngSci) is the founder and captain of U of T’s Space Travel Analog Research Team (START). She says that humans face a number of health risks outside of Earth’s atmosphere.
“Some of the physical hazards in space include lack of gravity, muscle atrophy, as well as differences in organ function,” she says.
“But another big one is galactic cosmic rays, or GCRs. As radiation comes into contact with the human body, one of the ways that it can impact us is by harming our DNA, which can have major implications for our everyday functions. We specifically wanted to look into double stranded DNA breaks.”
To study this, START created an experiment for the 7th Annual Canada Stratospheric Balloon Experiment Design Challenge hosted by the Canadian Space Agency at the Timmins Stratospheric Balloon Base in Timmins, Ont.
Last August, the team’s payload — known as START1 — was successfully launched and recovered from a height of 28659.4 metres.
The apparatus consisted of a pressurized vessel containing three flasks designed to contain human cell cultures, as well as a temperature control chamber and a shock absorption enclosure.
Through the flight, the team aimed to characterize the stratospheric radiation environment and evaluate the performance of environmental control systems during a stratospheric balloon flight.
“There’s so much more that went into it than I originally thought,” says Poffley.
“We had multiple safety checks before we could even get approved for take-off.”
These safety checks included vertical and lateral acceleration tests, as well as tests that used dry ice to assess whether the environmental control systems within their payload could maintain the 37 Celsius temperature that human cells require at atmospheric pressure.
While the team originally planned to test their system with live fibroblast cell lines, during its development they made the decision to instead focus on the environmental control aspects of their device, using it as a demonstration flight and generating data that can be extrapolated to longer missions and higher-radiation environments.
On the morning of the competition, they did one last integration test, hooked up their payload power system while the balloon envelope was being filled and were ready to go.
“It was very surreal after two years of work,” says Poffley.
“I’m holding the payload and they’re like ‘okay, 3, 2, 1,’ and then I let it go and it flies.”
With the successful recovery of their payload a few hours later, START is now able to validate the effectiveness of their temperature and pressure control mechanisms. They hope the payload can be flown in longer duration balloon flights for further research into the impact GCRs have on the human body.
The team’s work was recognized with the Innovation in Research Award at the competition, a huge accomplishment for a newer team in their first year of participation.
Their paper, START1: Modular Payload to Facilitate Ground-Based Galactic Cosmic Ray Research, was presented at the International Astronautical Congress 2025 in Australia in September.
Poffley says the team benefitted greatly from the mentorship of their advisor, Professor Kayley Walker in U of T’s Department of Physics, as well as from the diversity of the team.
“Working with a really strong team of primarily women has been empowering in itself,” says Poffley.
“I struggled to find my place in engineering in the first couple years of my undergrad, and it was cool to look at this interdisciplinary team and recognize myself and some of my experiences in my peers.”
As part of the competition, the team also hosted a 4-hour workshop with the National Society of Black Engineers high school conference, where they taught students how to build simple circuits and code in addition to talking about their stratospheric balloon flight.
“Our entire team recognizes the importance of exposing the future generation of engineers and those interested in STEM to this kind of work.”
The START team’s focus for the coming year will be to detail the work they did for future students to use.
“We’re making sure we have a really good paper trail, so if somebody wants to take on this project later and they have the time, they can pick up right where we left off.”
