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We test the long-term kinematical stability of a Galactic stellar halo model,due to Kafle, et al. (2012), who study the kinematics of approximately 5000blue horizontal branch (BHB) stars in the Sloan Digital Sky Survey (SDSS). Thevelocity dispersion $\sigma$ and anisotropy parameter $\beta$ of the stars havebeen determined as functions of Galactocentric radius, over the range$6<R_\mathrm{GC} < 25$ kpc, and show a strong dip in the anisotropy profile at$R_\mathrm{GC}\sim17$ kpc. By directly integrating orbits of particles in a 3-Dmodel of the Galactic potential with these characteristics, we show that the$\sigma$ and $\beta$ profiles quickly evolve on a time scale of a$\mathrm{few}\times10$ Myr whereas the density $\rho$ profile remains largelyunaffected. We suggest that the feature is therefore transient. The origin ofsuch features in the Galactic halo remains unclear.

Fading Features Found in the Kinematics of the Far-Reaching Milky Way Stellar Halo