A recent confirmation of the wide binary gravitational anomaly

X. Hernandez, Pavel Kroupa

Published 2024-10-22Version 1

Concerning recent published studies exploring the presence or otherwise of a gravitational anomaly at low accelerations in wide binary stars as observed by the {\it Gaia} satellite, Cookson (2024) presents an interesting case. In that study, RMS values of binned relative internal velocities in 1D for wide binaries are compared to Newtonian predictions for that quantity, with the author concluding that the data presented show no indication of any inconsistency with Newtonian expectations. However, the comparison presented is critically flawed, as the Newtonian predictions used refer to wide binaries with mean total masses of 2.0 $M_{\odot}$. This is larger than the 1.56 $M_{\odot}$ value which applies to the data used in said paper. In this short note we correct the error mentioned above and show that the data and error bars as given in Cookson (2024) are in fact inconsistent with Newtonian expectations. Contrary to the assertion by Cookson, the data presented in Cookson (2024) actually show a clear anomaly in the low acceleration gravitational regime, this being consistent with a number of independent studies yielding this same result. Based on the analysis by Cookson (2024), wide binary systems show a clear Milgromian deviation from Newtonian dynamics.