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Observational studies of pairs of galaxies have uncovered that theirdifferential line-of-sight velocities indicate the presence of a peak in theirthree-dimensional intervelocity distribution at 130-150 km/s. It had beenargued that galaxy pairs in the standard model of cosmology, $\Lambda$CDM,should not exhibit such an intervelocity peak, while Modified NewtonianDynamics (MOND) predicts such a preferred intervelocity for paired galaxies.However, no direct comparison with $\Lambda$CDM applying the same selectioncriteria and methodology as the observational studies has been performed yet,placing the comparison on unsure footing. To rectify this, we investigate thispotential challenge for $\Lambda$CDM by determining whether an analog of theobserved intervelocity peak is present in galaxy pairs within theIllustrisTNG-300 cosmological simulation. We identify galaxy pairs followingthe observational study's selection criteria, measure their projected velocitydifference, and analyse both the de-projected as well as the full velocitydifference for this galaxy pair sample in the simulation. We recover adeprojected intervelocity peak at ~130 km/s for galaxy pairs selected from thesimulation. The full three-dimensional velocity information available for thepairs in the simulation also reveals a clear preference for this intervelocity.The intervelocity peak among galaxy pairs does not appear to be a featureunique to MOND, but is also present in $\Lambda$CDM. It can thus not be claimedas a unique success of either theory over the other. Developing the galaxy pairintervelocity into a test of gravity in the low acceleration regime willrequire more detailed studies to identify measurable differences in the models.

The intervelocity of galaxy pairs in $\Lambda$CDM -- The observed velocity peak at ~130 km/s is not unique to MOND