During rocket launch, vehicles experience severe vibrations, shaking, and bending loads as they gain altitude. Spacecraft equipped with sensitive scientific instruments must withstand these loads without damage. To ensure reliability, NASA engineers conduct detailed analysis before rocket launch to determine how mechanical loads will affect each component of the spacecraft. This work is carried out by the Dynamic Environments Group within NASA's Launch Services Program. Specialists in this group work on improving methods for modeling shock and vibration effects to which rockets and payloads are subjected during launch. The new analytical approaches allow engineers to more accurately predict the behavior of the spacecraft structure under the physical forces that arise during launch and flight. This is especially important for protecting expensive and highly sensitive scientific instruments, which often form the core of a mission. Improved analytical methods contribute to increased reliability of NASA's space missions, reducing the risk of equipment damage from underestimated mechanical loads. This work is part of the agency's ongoing efforts to improve engineering processes that ensure the successful deployment of satellites and scientific spacecraft into orbit and their continued operation in the space environment.