Lightsails: Traveling the Cosmic Ocean

The lightsail is a form of space propulsion that is fundamentally different from the chemical rocket. Lightsails rely upon the momentum carried by photons in order to achieve thrust. Because of this, sailcraft have one key advantage over rockets---they have no need for on-board fuel. Sailcraft add a new level of versatility and durability in the field of space propulsion. In this work, we will introduce the basic Physics of lightsails. We will form the equation of motion of a sailcraft based upon the sun\u27s radiation pressure and gravity. Then, we will discuss some of the inherent limitations of light propulsion, such as dependence on nearby stars and materials challenges. In addressing these issues, we will introduce some potential ways of countering these flaws, such as systems of deep-space lasers used to beam light to sailcraft in interstellar space. We will also discuss considerations that go into designing a sailcraft, and even touch upon the basics of plotting sailcraft trajectories. Finally, we will discuss particular missions for which the lightsail is more suitable than the chemical rocket, and discover why the future of space propulsion will make use of both rocket and light propulsion