Extended Data Fig. 1. Outline of algorithm used to calculate β.
The Monte Carlo variables are outlined by dashed lines and are defined as follows: pre-impact orbit period Ppre; pre-impact orbit semimajor axis apre; Didymos ellipsoid extents Ax, Ay, Az; Dimorphos ellipsoid extents Bx, By, Bz; Dimorphos density ρB; post-impact orbit period Ppost; and net ejecta momentum direction . First, a secant algorithm iterates Didymos density ρA to match Ppre. Next, another secant algorithm iterates the along-track change in Dimorphos’s velocity ΔvT to match Ppost. Finally, M is calculated using the ellipsoid extents and density of Dimorphos, and then combined with ΔvT and to calculate β.