The Local Group as a test system for Modified Newtonian Dynamics

David Benisty, Eduardo I. Guendelman

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


The Local Group (LG) is an appropriate test system for Modified Newtonian Dynamics, since the acceleration of M31 galaxy is fully in the deep MOND regime a≪a0. We model the LG as a two body problem of M31 and the Milky Way (MW) galaxies. Extending previous studies, we also include the Cosmological Constant. The assumption that in the big bang the galaxies emerged from the same place and approach to the measured distance and velocity today (the Timing Argument), predicts the total mass for the LG: (0.447±0.005)⋅1012M. The corresponding motion of the LG predicts a past encounter. The ratio between the baryonic mass that MOND considers to the mass that Newtonian case predicted, which includes dark matter is 10.74±0.82. This ratio agrees with the ratio between the dark matter and baryonic matter in other galaxies.

Original languageEnglish
Article number100708
JournalPhysics of the Dark Universe
StatePublished - 1 Dec 2020

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The Local Group as a test system for Modified Newtonian Dynamics'. Together they form a unique fingerprint.

Cite this