Have you heard of light sails? The technique should make it possible to travel at speeds faster than 37,000 miles per second, which is roughly about one-fifth of the light speed. It sounds great as it may allow passengers to reach Alpha Centauri, the most famous nearby star aside from the Sun. In theory, we could even reach Proxima Centauri, which may be suitable for living, in approximately two decades.
The mechanism is quite simple – light pressure is used to make the objects move. The complication is the light sail is necessitated to reflect radiation to perform the action. In other words, an object like this needs to be able to exert reflection from most of radiation nearby, but also emit it to secure radiative chilling.
For now, this is just our imagination. The engineers are facing huge obstacles, but still looking for ways to design them. The trouble is that unimaginable features ought to be mixed. The light sail cannot be heavier than several grams or thicker than 100nm, but at the same time, it needs to be capable of resisting the severe radiative pressuring. Aside from firmness, it should also be about 10-15 feet when it comes to width.
An intriguing research was recently revealed in Pasadena, CA. A team of three scientists confirmed that there is a chance of building a structure like a light sail. According to them, the humanity could come up with a way to satisfy the requirements for materials. It’s the nanophotonic elements that scientists should strive to utilize to make everything possible.
It is a step forward because people tried carbon fibre, polymers, and aluminium, but despite their thinness, nothing work. The trick with nanophotonic materials is that they can balance between meeting the reflective specification and emission thanks to using certain scales for manipulating light.
The researchers pinpointed that constructors should consider using a blend of silica and silicon. The first has a meagre refracting index, but hefty characteristics to cool down radiation. Silicon offers paradoxical traits in both categories. The scientists suggested that the trade-off of raised-up reflection properties and obtaining a miniature mass for the sail should be measured with a new unit.
Solar Sail Was Already Tested
The idea has been present for over 100 years, but experts were waiting for the science to advance. Scientists yet need to unveil how to use light pressure to make a spaceship move. In the initial idea, researchers took inspiration from the Sun which can push a comet with its radiation. They believed sunlight may be used to create this pressure, but it is more realistic to use lasers.
The Japanese experimented with solar sail eight years ago. It took half a year to get close to Venus by utilizing only sunlight. These are still huge speeds, but a top-quality laser can be far stronger than Sun radiating. It is clear that it may offer significantly higher speeds, but everything is just theory now as it will take time to construct this type of object.