[2] The object is of a particular note for astrophysicists, because gravitational lensing studies of the Bullet Cluster are claimed to provide strong evidence for the existence of dark matter.

The stars of the galaxies, observable in visible light, were not greatly affected by the collision, and most passed right through, gravitationally slowed but not otherwise altered.

The hot gas of the two colliding components, seen in X-rays, represents most of the baryonic, or "ordinary", matter in the cluster pair.

Furthermore, the dark matter clump, revealed by the weak lensing map, is coincident with the collisionless galaxies, but lies ahead of the collisional gas.

[12]According to Eric Hayashi: The velocity of the bullet subcluster is not exceptionally high for a cluster substructure, and can be accommodated within the currently favoured Lambda-CDM model cosmology.

[16] Mordehai Milgrom, the original proposer of modified Newtonian dynamics, has posted an online rebuttal[17] of claims that the Bullet Cluster proves the existence of dark matter.