Developing graphic interfaces to steer high-performance scientific computations has been a research subject in recent years. Now, computational scientists are starting to use virtual reality environments to explore the results of their simulations. In most cases, the virtual reality environment acts on precomputed data; however, the use of virtual reality environments for the dynamic steering of distributed scientific simulations is a growing area of research. We present in this paper the initial design and implementation of a distributed system that uses our virtual reality environment, the CAVE, to control and steer scientific simulations being computed on remote supercomputers. We discuss some of the more relevant features of virtual reality interfaces, emphasizing those of the CAVE, describe the distributed system developed, and present a scientific application, the Cosmic Worm, that makes extensive use of the distributed system.