3D spatial structure of HSC 2986 and its ellipsoidal curves (left). The black dashed line indicates the unnormalized MD of HSC 2986. Other symbols and curves are the same as those in Fig. 2. 3D spatial structure of HSC 2986 (right). The purple and black dots are divided by the Gaussian mixture model (GMM) method, with the red dashed line meaning the unnormalized MD of HSC 2986. The purple and black pentagrams are the maximum points of the density of the purple and black scatter distribution.