ESA Science & Technology - Simulated Athena mosaic of Andromeda

This speckling of magenta and red dots comprises a simulated X-ray view of one of the most famous galaxies in our skies: the Andromeda galaxy (also known as M31).

This image, created in 2018 using the SIXTE (SImulation of X-ray TElescopes) software package, is a simulation of what ESA's future Athena X-ray observatory will see when it observes Andromeda after the telescope's launch in the early 2030s.

Andromeda is home to a vast population of X-ray sources, including remnants of supernova explosions and binary systems comprising a compact stellar remnant – a white dwarf, neutron star or black hole – exerting an intense gravitational pull onto a companion star, from which it strips material via an accretion disc.

Athena is equipped with two incredibly precise instruments, the Wide Field Imager (WFI) and the X-ray Integral Field Unit (X-IFU). This image, spanning about two degrees on each side, is a mosaic of ten simulated observations with Athena's WFI instrument, each lasting 10 000 seconds (just over two and a half hours). This imager's sensitivity and surveying speed will top even the most powerful X-ray observatories active today, allowing Athena to generate the most accurate catalogue of X-ray sources ever created.