By Catharina Slot Pihl, AAU Communication and Public Affairs
Photos: Ida Marie Jensen

The project members are four former physics students: Casper Pedersen, Hans Larsen, Ali Sepas and Claudia Larsen, who along with their supervisors, Thomas Tauris and Christophe Biscio, have studied how black holes are formed – and especially how their axis of rotation can change at birth.

New angle on the birth of black holes

The research project is based on gravitational wave data from LIGO and Virgo where the group analyzed 38 black hole mergers. The results show that the rotation axes of black holes often do not point in the same direction - a phenomenon that can be explained by a "cosmic kick" during the supernova explosion that changes the direction of the black hole's rotation. This has been hypothesized before, but what is new about this project is the statistical method that the former students used to support the theory. This led to a publication that contributes new knowledge to astrophysics – and that has attracted international attention. 

Three international publications from AAU students

The latest article in New Astronomy marks the third time that Casper Pedersen and Hans Larsen have had their work published in an international peer-reviewed journal. Throughout their studies, they worked closely with their AAU research group on projects that have attracted attention in the international research community. The first time they were published was an article on supernovae in Nature in 2024, followed by a publication in The Planetary Science Journal in the spring of 2025 based on their eighth semester project. The latest publication builds on the previous work and is yet another example of how a student project can develop into research with international impact.

Research as a student: "A huge pat on the back"

Casper Pedersen and Hans Larsen graduated with MSc degrees in Physics in the summer of 2025, but their research journey already began during their studies. Having research published as students has been a great experience for both of them.

"It's an amazing experience to be able to contribute to relevant research while you're still a student. To have your work published in an international journal again is a huge pat on the back and recognition of the effort you’ve put into your studies," they say.

A call to future researchers

Although Casper and Hans have now graduated, they hope that their work can inspire other students to throw themselves into research – especially in astrophysics. And they offer the following encouragement:

"Of course, we hope that our work can inspire more people to do research on astrophysics – especially students. There is still a lot we don't know, so we have countless opportunities to learn more about what’s going on in the night sky – and where we ourselves come from."

Casper and Hans' experience underscores the value of early involvement in research and shows how commitment and academic curiosity can lead to actual results – even before an academic career has really begun.

Translated by LeeAnn Iovanni, AAU Communication and Public Affairs.