Galaxy clusters as seen by XMM-Newton

These X-ray images of the clusters of galaxies ‘Sersic 159-03’(right) and ‘2A 0335+096’ (left) were taken by the European Photon Imaging Camera (EPIC) on-board ESA’s XMM-Newton, in November 2002 and August 2003 respectively.

Thanks to these observations, astronomers could determine the abundances of nine chemical elements in the clusters ‘plasma’ – a gas containing charged particles such as ions and electrons.
These elements include oxygen, iron, neon, magnesium, silicon, argon, calcium, nickel, and - detected for the first time ever in a galaxy cluster - chromium.

The distribution of silicon (produced by ‘type Ia’ and ‘core collapse’ supernova types) relative to iron (mainly produced by ‘type Ia’ supernovae) in these two clusters is very different, showing that they had a different evolution.