On Sunday 10 June 2012 the X-ray space observatory XMM-Newton has been 12,5 years in orbit. Over these 12.5 years many important discoveries were made and SRON played an important role. The RGS instrument built by SRON & partners was a key instrument in discovering problems with cooling flow models in clusters of galaxies, leading to a revolution in our view of how these systems work and interact with supermassive black holes, and even having consequences for galaxy formation theories.

Even 12.5 years after launch, observing time is oversubscribed by a factor of 7, and every day a refereed paper based on XMM-Newton data is published. The instruments, including the instrument provided by SRON and its collaborators, are still working as expected and, unless some unexpected problems arise, SRON researchers expect to be able to continue this mission for another 10 years. Reaching the 25th anniversary is probably too ambitious but analysis of the data will certainly continue.