2011/05/27 by P. J. E. Peebles, Peebles, P. J. E., R. Brent Tully +4 · 1 citation
Mathematics · Physics and Astronomy · #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #advanced mathematical theories #astro-ph.CO
paper · pdf · doi:10.48550/arxiv.1105.5596
27 pages, 7 figures
arxiv created 2011/05/27 · openalex publication_date 2011/05/27 · arxiv updated 2011/05/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This dynamical model for the 28 galaxies with distances less than 1.5 Mpc, and not apparently tight satellites, is constrained by the initial condition that peculiar velocities at high redshift are small and growing in accordance with the standard cosmology. The solution is a satisfactory fit to most of the measured redshifts, distances, and proper motions, with some interesting exceptions that call for further investigation. The model predicts Milky Way rotation speed 256 km/s, consistent with Reid et al. (2009a). Ten Local Group galaxies emanate from low supergalactic latitude and supergalactic longitude ~ 70 degrees, perhaps as remnants from failed assembly of a larger galaxy. NGC 6822 passes close to the Milky Way at redshift ~0.27, in an orbit similar to the Magellanic Clouds. Leo I has heliocentric angular velocity 0.33 mas/yr, perhaps measurable by the mean stellar motion, and 15 galaxies have proper motions greater than 0.05 mas/yr, measurable for any with masers.