Could Solar Sails Bring Us to the Stars ?
The idea of a Solar sail is nothing new, in 1608 Johannes Kepler discussed the idea with Galileo Galilea, and while it was a couple of hundred years later, and the birth of rocketry to become more popularised, it wasn't until 1999 that work began on one.
Early designs focused on harnessing the photons fired from the Sun, which of course makes sense, as it's a limitless source, however more recent advances in Lasers have shown, that they can deliver far more energy over much further distances.
A conventional rocket using current technology would require about 80,000 years to reach our nearest star system Alpha Centuari, and would have no capacity to slow down and enter orbit, it would be a momentary passage at that, so the Breakthrough Starshot initiative was created in 2015, with the backing of Stephen Hawking and Yuri Milner, 100 million US dollars to create a craft able to cut that 80,000 years down to just 20.
Scientists working with Starshot have not only discovered materials needed to both withstand the laser beams while still being incredibly light and the thickness of a human hair.
All this is set out in a paper by the University of Pennsylvania, along with the most optimum shape of the craft.
There's still a long way to go to prove itself, but the theories are coming together, and it may be that the first interstellar craft are huge sails sped up to near the speed of light, to cross 268,142 AU (4.24 light years) *1 AU is the distance between the Earth and the Sun)
Sources:
https://astronomy.com/news/2022/03/developing-light-sail-technology-billows-into-the-future
https://www.eurekalert.org/news-releases/943728
https://breakthroughinitiatives.org/about
https://www.planetary.org/articles/what-is-solar-sailing#:~:text=When%20was%20the%20solar%20sail,Cosmos%201%20solar%20sail%20spacecraft.
