**1. Introduction**

The history of nuclear propulsion can be traced back to the mid-twentieth century when the development of the atomic bomb and the dawn of the nuclear age sparked a new era of technological innovation and exploration. As the world rapidly discovered nuclear technology's tremendous power and potential, scientists and engineers began exploring new ways to harness this power for practical applications.

One of the earliest and most promising applications of nuclear technology was nuclear propulsion, which offered the potential to revolutionize space travel, naval operations, and air transportation. The first experimental reactors for nuclear propulsion were developed in the late 1940s and early 1950s. By the mid-1950s, the United States had launched the first nuclear-powered submarines, the USS Nautilus and the USS Seawolf [1].

The development of nuclear propulsion was driven by several critical factors, including the increasing demand for longer-range and more capable vessels, the growing interest in space exploration, and the need for a more efficient and reliable power source. Nuclear propulsion offers several key advantages over conventional propulsion systems, including higher energy density, greater operational efficiency, and reduced dependence on fuel resupply.

Despite its many benefits, nuclear propulsion also posed significant challenges and risks, including the need for safe and reliable power sources, effective shielding to protect against radiation exposure, and rigorous regulatory and licensing processes. These challenges led to the development of new technologies and processes for designing and operating nuclear propulsion systems. By the end of the twentieth century, nuclear propulsion had become a critical component of many military and space programs.

Today, nuclear propulsion plays a critical role in naval operations. Nuclear propulsion will play an essential role in space travel in the near future. Aero-nuclear propulsion continues to evolve and improve as new technologies and processes are developed. While the use of nuclear propulsion is still subject to challenges and risks, it remains one of the most promising and innovative applications of nuclear technology. It will likely continue to play a critical role in the world's technological and scientific advancement for many years to come.
