There's an excellent book [1] about this adventure written by its senior scientific advisor (Pierre Léna). The flight went under the shadow of the moon for 74 minutes !

[0] https://www.ina.fr/ina-eclaire-actu/30-juin-1973-le-concorde...

[1] https://www.fnac.com/a17820796/Pierre-Lena-Soleils-eclipses