She obtained a PhD (doctorate) from the University of Grenoble 1 in 1995, with her thesis titled Structure et cinématique de l'univers local.

[3] In 2017, Courtois revealed two discoveries: one, called the Dipole repeller, and the other, on the cosmic microwave background cold spot, which could potentially explain the propagation of our galaxy through space at about 2 million kilometres per hour.

It is one of the world leaders in the field of cosmology dedicated to the observation, analysis and digital reproduction of the distribution and dynamics of dark matter and galaxies in the nearby universe.

Courtois has been an expert adviser at the European Commission for research and education programmes in physics and astrophysics since 2009.

[6][7] In 2015, Courtois was named a senior member of the Institut Universitaire de France[5] and was made a chevalier of the Ordre des Palmes Académiques.

[8] She also received a festival prize for her film Cartographier l'univers : à la découverte de Laniakea.

[9] Her book Voyage sur les flots de galaxies won the 2017 Prix Ciel & Espace du livre d'astronomie.