Simulated galaxy haloes

This set of six simulated images shows ‘low surface brightness’ structures in the haloes surrounding galaxies. These structures look like faintly glowing arcs spreading outwards from the galaxies’ central discs.  

Importantly, the structure of a galaxy’s halo can reveal a lot about how the galaxy formed. For example, stellar streams such as the arcs shown here are the remnants of smaller galaxies or star clusters that were torn apart while merging with the host galaxy.  

ESA's Arrakihs mission plans to study the stellar haloes of at least 80 nearby galaxies with a similar mass to the Milky Way galaxy. This is a large enough number to get statistics on how a ‘typical’ galaxy forms, allowing us to understand how unique our home galaxy is.  

These simulations were made with the FIREBox suite of simulations. 

[Image description: A three-by-two grid of images showing galaxies and their haloes on a black background. Each image has a central spiral galaxy seen face-on, glowing brightly in blue and/or yellow tones. These are surrounded by hazy white-yellow glowing arcs, swirling outward, as well as some small satellite galaxies looking like bright blobs. No two galaxies look the same.]