The multichord stellar occultation on 2019 October 22 by the trans-Neptunian object (84922) 2003 VS\(_2\)

We predicted, observed, and analyzed the multichord stellar occultation of the Second Gaia Data Release (Gaia DR2) source 3449076721168026624 (m\(_v\) = 14.1 mag) by the plutino object 2003 VS\(_2\) (hereafter, VS\(_2\)) on 2019 October 22. We also carried out photometric observations to derive the rotational light curve amplitude and rotational phase of VS\(_2\) during the stellar occultation. Combining the results and assuming a triaxial shape, we derived the 3D shape of VS\(_2\). Out of the 39 observatories involved in the observational campaign, 12 sites reported a positive detection; this makes it one of the best observed stellar occultations by a TNO so far. We obtained a rotational light curve amplitude of \({\Delta}\)m = 0.264 \(\pm\) 0.017 mag, a mean area-equivalent diameter of D\(_{A_{eq}}\) = 545 \(\pm\) 13 km, and a geometric albedo of 0.134 \(\pm\) 0.010. The best triaxial shape obtained for VS\(_2\) has semiaxes a = 339 \(\pm\) 5 km, b = 235 \(\pm\) 6 km, and c = 226 \(\pm\) 8 km. The derived aspect angle is \({\theta}\) = 59\({\deg} \pm\) 2\({\deg}\) or its supplementary \({\theta}\) = 121\({\deg} \pm\) 2\({\deg}\), depending on the north-pole position. The spherical-volume equivalent diameter is D\(_{V_{eq}}\) = 524 \(\pm\) 7 km. If we consider large albedo patches on its surface, the semi-major axis of the ellipsoid could be ~10 km smaller. These results are compatible with the previous ones determined from the single-chord 2013 and four-chord 2014 stellar occultations and with the effective diameter and albedo derived from Herschel and Spitzer data. They provide evidence that VS\(_2\)'s 3D shape is not compatible with a homogeneous triaxial body in hydrostatic equilibrium, but it might be a differentiated body and/or might be sustaining some stress. No secondary features related to rings or material orbiting around VS\(_2\) were detected.