Top: gravitational field of the Didymos shape models (for the mass and volume nominal values) with 2000, 6716, 20 000, and 3 145 728 facets vs. distance in two directions: equatorial x-axis, (x, 0, 0) (blueish lines), and rotation axis, (0, 0, z) (magenta lines). The gravitational field of the equivalent volume sphere is shown as a solid black line. Bottom: relative error of the gravitational field generated by the 6716-facet model vs. the spherical approximation as a function of distance (r). The gray points correspond to random (x, y, z) positions, and the blue line represents the relative error along the x-axis. For distances >2300 m, the relative error on gravity stays below 5% (dashed black line).