Abstract: A boom assembly for a rocket-launched spacecraft, the boom assembly comprising a plurality of rigid sections and a plurality of elastic sections that pivotally connect each of the rigid sections together so as to enable the boom assembly to be folded into a storage configuration and so as to enable the boom assembly to be automatically unfolded into a deployed configuration that provides the spacecraft with a large rigid extending platform. At least one of the rigid sections is mounted to the spacecraft so as to secure the boom assembly to the spacecraft. In one embodiment, a plurality of extendable components, such as solar panels and radar antennae, are mounted to the rigid sections so as to allow for storing and deploying the extendable components. In another embodiment, there may be no components mounted other than a length of wire or a length of metal tape which will allow the boom to act as an antenna.