A downhole tool orientation determination system to determine a radial orientation of a tool conveyed downhole into a pipe via a carrier and a method of determining a radial orientation of a tool conveyed downhole into a pipe via a carrier are described. The system includes an orientation tool conveyed downhole by the carrier that conveys the tool, and a distributed acoustic sensor (DAS). The DAS includes an optical fiber disposed axially along an outer surface of the pipe; and a processor to determine an orientation of the orientation tool with respect to the optical fiber based on a measurement by the optical fiber at different rotational positions of the orientation tool. The processor determines the radial orientation of the tool with respect to the optical fiber based on the orientation of the orientation tool with respect to the optical fiber.