English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We compare spherically-averaged radial number counts of bright (> 10^5 Lsun)dwarf satellite galaxies within 400 kpc of the Milky Way (MW) and M31 and findthat the MW satellites are much more centrally concentrated. Remarkably, thetwo satellite systems are almost identical within the central 100 kpc, whileM31 satellites outnumber MW satellites by about a factor of four at deprojecteddistances spanning 100 - 400 kpc. We compare the observed distributions tothose predicted for LCDM suhbalos using a suite of 44 high-resolution ~10^12halo zoom simulations, 22 of which are in pairs like the MW and M31. We findthat the radial distribution of satellites around M31 is fairly typical ofthose predicted for subhalos, while the Milky Way's distribution is morecentrally concentrated that any of our simulated LCDM halos. One possibleexplanation is that our census is bright (> 10^5 Lsun) MW dwarf galaxies issignificantly incomplete beyond ~ 100 kpc of the Sun. If there were ~8 - 20more bright dwarfs orbiting undetected at 100 - 400 kpc, then the Milky Way'sradial distribution would fall within the range expected from subhalodistributions and alos look very much like the known M31 system. We use oursimulations to demonstrate that there is enough area left unexplored by theSloan Digital Sky Survey and its extensions that the discovery of ~10 newbright dwarfs is not implausible given the expected range of angular anisotropyof subhalos in the sky.

On the stark difference in satellite distributions around the Milky Way and Andromeda