Teaching abstract topics, such as concepts in Modern Physics, has been known to be challenging due to the unattainable nature of some real world experiences. Hence, creating a Virtual Learning Environment (VLE) offers a promising solution in bringing the learner closer to the experiences by simulating such an environment and immersing the user. In this work, we investigated the learning outcome of teaching the concept of Gravity Assist in a VLE. Gravity Assist, also known as the Gravitational Slingshot or Swing-By, is a method to accelerate or decelerate space probes by conducting an exchange of momentum with a planet. As this is one of the numerous topics in Modern Physics which require abstract multidimensional thinking, our research question was to assess the performance of a VLE on this particular field, since virtual reality offers depth impression, interactivity and immersion - parameters observed and discussed in this study. Conducting a user study where thirty participants - primarily students - were tested on their prior knowledge in a pre-questionnaire as well as their gained knowledge and their level of immersion in a post-questionnaire, we found that our VLE provides excellent results in teaching this topic; In average an improvement of 42.7% for Learning Evaluation Questions.