Institute for Astronomy | University of Hawaii | 2017 Dec 07
A team of astronomers from Maryland, Hawaii, Israel, and France has produced the most detailed map ever of the orbits of galaxies in our extended local neighborhood, showing the past motions of almost 1400 galaxies within 100 million light years of the Milky Way.
The team reconstructed the galaxies' motions from 13 billion years in the past to the present day. The main gravitational attractor in the mapped area is the Virgo Cluster, with 600 trillion times the mass of the Sun, 50 million light years from us. Over a thousand galaxies have already fallen into the Virgo Cluster, while in the future all galaxies that are currently within 40 million light years of the cluster will be captured. Our Milky Way galaxy lies just outside this capture zone. However the Milky Way and Andromeda galaxies, each with 2 trillion times the mass of the Sun, are destined to collide and merge in 5 billion years. ...
These dramatic merger events are only part of a larger show. There are two overarching flow patterns within this volume of the universe. All galaxies in one hemisphere of the region - including our own Milky Way - are streaming toward a single flat sheet. In addition, essentially every galaxy over the whole volume is flowing, as a leaf would in a river, toward gravitational attractors at far greater distances. ...
Action Dynamics of the Local Supercluster - Edward J. Shaya et al
- Astrophysical Journal 850(2):207 (2017 Dec 01) DOI: 10.3847/1538-4357/aa9525
arXiv.org > astro-ph > arXiv:1710.08935 > 24 Oct 2017 (v1), 27 Oct 2017 (v2)