The cosmological model of the expanding balloon in 4D-space (CM) delivers in interaction with a homogeneous vector field exactly Newton’s law of gravitation with its 1/r-shape of the gravitational funnel. So far, the depth of space, W, in the 4-th spatial dimension can only be calculated using the theoretical approach of Feynman’s radius of excess rex=a/3 with Schwarzschild-radius a. With this, the connection to the general theory of relativity (GR) is established, but the situation is unsatisfactory. In the present study, the possibilities of an experimental approach to the calculation of spatial depth, W, are explored. The only experimental approach so far is the bending of light on a central mass. We hypothesize in addition to the main effect φ = -4a/y, i.e., the angle of diffraction of a light beam on a heavy central mass in the distance y and with Schwarzschild-radius a, an additional effect close to the center of the form φC ~ -1/y4. This additional effect has on the edge of the central mass about 1/3 of the strength of the main effect. However, its influence disappears very quickly with increasing distance. For this reason the sun cannot be used as the central mass. The bright corona and the strong magnetosphere do not allow measurements close to the sun. However, ESA’s GAIA mission puts the planet Jupiter at the center of interest. This spacecraft measures with extremely high precision the positions of billions of stars. Results of first data analyses have already been published. As a side effect - the application of the CM to small particles provides an indication that the radius of the electron could be in the order of 10-23 m.