Asteroseismology of massive stars in the young open cluster NGC 884: a status report

To improve our comprehension of the beta Cephei stars, we set up a photometric multi-site campaign on the open cluster NGC 884 (Chi Persei). Thirteen telescopes joined the 2005-2007 campaign which resulted in almost 78000 CCD frames. We present an up-to-date status of the analysis of these data, in which several interesting oscillating stars are pointed out. We end with the future prospects.