Draco Tidal Tails

The Draco dwarf spheroidal galaxy shows structural distortions and possible tidal tail features whose amplitude is difficult to explain given Draco's inferred orbit around the Milky Way and the standard NFW dark matter halo profiles that ΛCDM assigns to both the Milky Way and Draco. The tidal stripping rate depends on the tidal force at pericentre, which is set by the Milky Way's enclosed mass profile, and on Draco's binding energy per unit mass. If Draco's stars are as loosely bound as its observed velocity dispersion suggests given its luminosity, the expected tidal stripping should be more extensive than observed; if the binding energy is boosted by a cuspy dark matter core as NFW predicts, the tidal tails should be less prominent. Neither limit satisfies all constraints simultaneously within ΛCDM. Successive Collision Theory resolves this through gravitational superposition: the Milky Way's effective gravitational field is augmented by the overlapping gravitational wells of the nested comoving frame hierarchy above it.

This superposition adds effective gravitational influence to the Milky Way's potential without requiring additional dark matter particles. The consequence for Draco's tidal evolution is that the tidal force at pericentre is somewhat higher than the Milky Way's visible mass or standard NFW halo predicts, enhancing tidal stripping and making the observed tidal distortions consistent with Draco's observed stellar kinematics. Simultaneously, the core-cusp problem addressed by SCT for dwarf spheroidals produces a cored density profile in Draco rather than the NFW cusp; a cored satellite is more susceptible to tidal stripping and develops more extended tidal tails per unit orbital energy than a cuspier satellite. These two SCT effects — enhanced tidal field from frame superposition, and cored internal density profile from angular momentum support — together bring Draco's tidal morphology into quantitative consistency with its observed velocity dispersion and luminosity profile without invoking fine-tuned dark matter halo parameters.