Intergalactic shock fronts

Understand

When galaxy clusters collide, they generate shock fronts in the hot intracluster medium.

• Observations of these shocks can provide valuable information on the merger dynamics and physical conditions in the cluster plasma, and even help constrain the nature of dark matter.
• To study shock fronts, one needs an X-ray telescope with high angular resolution (such as Chandra), and be lucky to see the merger from the right angle and at the right moment.
• As of this writing, only a handful of merger shock fronts have been discovered and confirmed using both X-ray imaging and gas temperature data -- those in 1E0657-56, A520, A754, and two fronts in A2146.