Figure 48

Figure 48: The acceleration parameter ∼ V4f ∕ (GMb ) of extragalactic systems, spanning ten decades in baryonic mass M b. X-ray emitting galaxy groups and clusters are visibly offset from smaller systems, but by a remarkably modest amount over such a long baseline. The characteristic acceleration scale √ -- a0 ∼ Λ is in the data, irrespective of the interpretation. And it actually plays various other independent roles in observed galaxy phenomenology. This is natural in MOND (see Section 5.2), but not in ΛCDM (see Section 4.3).