Characterizing the properties of the host galaxies of merging compact objects provides essential clues to interpret current and future gravitational-wave detections .
Here , we investigate the stellar mass , star formation rate ( SFR ) , metallicity and colours of the host galaxies of merging compact objects in the local Universe , by combining the results of mobse population-synthesis models together with galaxy catalogs from the eagle simulation .
We predict that the stellar mass of the host galaxy is an excellent tracer of the merger rate per galaxy { n } _ { GW } of double neutron stars ( DNSs ) , double black holes ( DBHs ) and black hole-neutron star binaries ( BHNSs ) .
We find a significant correlation also between { n } _ { GW } and SFR .
As a consequence , { n } _ { GW } correlates also with the r - band luminosity and with the g - r colour of the host galaxies .
Interestingly , \gtrsim { } 60 % , \gtrsim { } 64 % and \gtrsim { } 73 % of all the DNSs , BHNSs and DBHs merging in the local Universe lie in early-type galaxies , such as NGC 4993 .
We predict a local DNS merger rate density of \sim { } 238 Gpc ^ { -3 } yr ^ { -1 } and a DNS merger rate \sim { } 16 - 121 Myr ^ { -1 } for Milky Way-like galaxies .
Thus , our results are consistent with both the DNS merger rate inferred from GW170817 and the one inferred from Galactic DNSs .