Authors: Eleni Nikou (George Mason University, Department of Physics and Astronomy, 4400 University Drive, Fairfax, VA 22030, USA), Jie Zhang (George Mason University, Department of Physics and Astronomy, 4400 University Drive, Fairfax, VA 22030, USA)

Coronal mass ejections (CMEs) are large-scale solar eruptions that carry plasma and magnetic field into the interplanetary space. Studying their initial stages and evolution is of great importance since they are one of the space weather drivers. Most CMEs show a two front structure that consists of the ejecta and the shock. In this work we study the 3D evolution and kinematics of the ejecta in the outer corona using multi-viewpoint white light observations. COR2/ STEREO, C2 and C3/ LASCO data are used to study the CMEs. To track the CMEs we use a fitting tool that applies the MPFIT minimization IDL routine and combines multi-viewpoint observations with the Graduated Cylindrical Shell model (GCS model) point cloud to obtain the best values of its geometric parameters along with their uncertainties. The evolution of the propagation direction and size of CMEs along with their uncertainties will be analyzed and presented.