Supernovae data: Cosmological Constant or ruling out the Cosmological   Principle ?
  Analysed in the framework of homogeneous FLRW models, the magnitude-redshift data from high redshift supernovae yield, as a primary result, a strictly positive cosmological constant. Another reading of the currently published measurements does not exclude a possible ruling out of the Cosmological Principle and, thus, also, of the cosmological constant hypothesis. It is shown how shortly coming data can be used to settle this fondamental issue, pertaining to both cosmology and particle physics. 
Marie-No\"elle C\'el\'erier (Observatoire de Paris-Meudon)