Calderón Bustillo, JuanLeong, Samson H. W.Dietrich, TimLasky, Paul D.2026-02-112026-02-112021-04-30Juan Calderón Bustillo et al 2021 ApJL 912 L10https://hdl.handle.net/10347/45833This is the Accepted Manuscript version of an article accepted for publication in The Astrophysical Journal Letters. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.3847/2041-8213/abf502The joint observation of the gravitational-wave (GW) and electromagnetic (EM) signal from the binary neutron-star merger GW170817 allowed for a new independent measurement of the Hubble constant H0, albeit with an uncertainty of about 15% at 1σ. Observations of similar sources with a network of future detectors will allow for more precise measurements of H0. These, however, are currently largely limited by the intrinsic degeneracy between the luminosity distance and the inclination of the source in the GW signal. We show that the higher-order modes in gravitational waves can be used to break this degeneracy in astrophysical parameter estimation in both the inspiral and post-merger phases of a neutron star merger. We show that for systems at distances similar to GW170817, this method enables percent-level measurements of H0 with a single detection. This would permit the study of time variations and spatial anisotropies of H0 with unprecedented precision. We investigate how different network configurations affect measurements of H0, and discuss the implications in terms of science drivers for the proposed 2.5- and third-generation GW detectors. Finally, we show that the precision of H0 measured with these future observatories will be solely limited by redshift measurements of EM counterparts.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal article10.3847/2041-8213/abf502open access