Space missions need software in order to be aware of the occurrence of geometric events in different phases of their project lifecycle. However, current software packages that provide capabilities to search for geometric events might lack desirable software qualities such as extensibility and reusability, and some conflate the definition of events with the search for the same. In order to improve the state of the art, we propose a framework named Tychonis that, via metamodeling techniques and conscious use of object-oriented design best practices, (i) can integrate with current and future mission software, (ii) enables end-users to extend opportunities and search algorithms without modifying the tools that use the framework, and (iii) promotes the cross-mission reusability of the framework and its extensions. These attributes make it less costly for projects to develop software to search for geometric events. Tychonis is provided as a software library that allows missions to add their own data structures and constructs to the framework, including geometric event types and search algorithms. This is accomplished with Tychonis’ use of the Eclipse Modeling Framework (EMF) to capture its metamodel, which enables the generation of Java classes that represent built-in or user-developed Tychonis constructs. In the present paper, we elaborate on the impetus for the development of Tychonis, present its proposed design and use, and discuss growth opportunities for future consideration. Peer Reviewed