Why don't you actually read the following post before responding?
'Offset between dark matter and ordinary matter: evidence from a sample of 38 lensing clusters of galaxies'
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2010.16739.x/abstract
"We compile a sample of 38 galaxy clusters which have both X-ray and strong lensing observations, and study for each cluster the projected offset between the dominant component of baryonic matter centre (measured by X-rays) and the gravitational centre (measured by strong lensing). Among the total sample, 45 per cent clusters have offsets [greater than]10 arcsec. The [greater than]10 arcsec separations are significant, considering the arcsecond precision in the measurement of the lensing/X-ray centres. This suggests that it might be a common phenomenon in unrelaxed galaxy clusters that gravitational field is separated spatially from the dominant component of baryonic matter. It also has consequences for lensing models of unrelaxed clusters since the gas mass distribution may differ from the dark matter distribution and give perturbations to the modelling. Such offsets can be used as a statistical tool for comparison with the results of Lambda cold dark matter ( CDM) simulations and to test the modified dynamics."
The offset is due to the galaxy clusters moving through the aether. The analogy is a submarine moving through the water. You are under water. Two miles away from you are many lights. Moving between you and the lights one mile away is a submarine. The submarine displaces the water. The state of displacement of the water causes the center of the lensing of the light propagating through the water to be offset from the center of the submarine itself. The offset between the center of the lensing of the light propagating through the water displaced by the submarine and the center of the submarine itself is going to remain the same as the submarine moves through the water. The submarine continually displaces different regions of the water. The state of the water connected to and neighboring the submarine remains the same as the submarine moves through the water even though it is not the same water the submarine continually displaces. This is what is occurring physically in nature as the galaxy clusters move through the aether.
"Our data strongly support the idea that the gravitational potential in clusters is mainly due to a non-baryonic fluid, and any exotic field in gravitational theory must resemble that of CDM fields very closely."
The non-baryonic fluid is the aether.