NASA is supposed to implement a sustainable and affordable human and robotic program to explore the solar system and beyond as it is the first goal of The Presidents Vision for U.S. Space Exploration. The robotic exploration across the solar system consists of exploring Jupiters moons, asteroids and other bodies to search for evidence of life, and to understand the history of the solar system. Trajectory generation for a robotic vehicle is an essential part of the total mission planning. To save energy by exploiting possible situation such as wind will assist a robotic explorer extend its life span and perform tasks more reliably. In this paper, we propose to utilize Nonlinear Trajectory Generation (NTG) methodology to generate 3D opportunistic trajectories for an Aerobot by exploiting wind. The Aerobot is dynamically controlled by three propellers which are respectively parallel to the local three Cartesian axes. Constraints for the Aerobot control are derived from Euler-Lagrange equations since the Aerobot satisfies with the Lagrange-D'Alembert principle. The new proposed Aerobot model takes the aerodynamics into account. The results show that NTG can take the advantage of wind profiles to save significant energy for the defined goal.