Stephen Hawking is a cosmologist, professor, theoretical physicist and one of the greatest living scientific legends. He, along with Yuri Milner, an entrepreneur, venture capitalist, and physicist, as well as Mark Zuckerberg of Facebook fame, announced the Breakthrough Starshot initiative in April of 2016.
According to the website, Breakthrough Starshot is a “$100 million research and engineering program aiming to demonstrate proof of concept for a new technology, enabling ultra-light unmanned space flight at 20% of the speed of light; and to lay the foundations for a flyby mission to Alpha Centauri within a generation.”
Let’s break this down to understand what manner of science fiction we’re dealing with here.
Alpha Centauri is our neighboring star system that is located four light years away. With current rocket propulsion technology – our current abilities to drive or push a rocket forward – it would take hundreds of millennia to reach it.
The Speed of Light
In the past fifteen years, fast technological advances have opened up the possibility of light-powered space travel at a significant fraction of light speed. The speed of light is 671 million miles per hour. According to the statement from Breakthrough Starshot, the program would push miniature space probes to speeds up to 100 million miles per hour, roughly 20% the speed of light.
The program would include a light beamer – basically a number of high powered lasers – located on earth, that would push nanocrafts to their top speeds.
Nanocrafts you say?
These are gram-scale robotic spacecrafts comprising two main parts:
- A “StarChip”, which is a wafer sized component carrying cameras, photon thrusters, power supply, navigation and communication equipment, and constituting a fully functional space probe.
- The “LightSail” is a meter-scale sail that is no more than a few hundred atoms thick and at gram-scale mass.
So, you could picture little wafer sized components surrounded by what look like sails, that lasers from earth push to speeds of 100 million miles per hour. Crazy, right?
The scientists explain that a few technological advances are making this invention possible. First is the idea of Moore’s Law, which is the observation made by Gordon E. Moore in 1975, that explains that the number of transistors in dense integrated circuits will double approximately every two years. Basically, technology will only get smaller. We’ve seen evidence of this over the decades and this observation has proved true every two years up to about 2013. Its still a viable prediction for scientists to work with, but the rate at at which technology is advancing is indeed slowing down. Not dramatically, but it may perhaps change to every 3 or 4 years that we see a shift in scale of technological advances.
The second advancement in technology that is making nanocrafts a possibility are the advances in nanotechnology. Nanotechnology is science, engineering, and technology conducted at the nano-scale, which is about 1 to 100 nano-meters. Nano-science and nanotechnology are the study and application of extremely small things and can be used across all the other science fields, such as chemistry, biology, physics, materials science, and engineering. These advances are becoming more and more a reality.
Once the nanocrafts reach Alpha Centauri in a few decades, they would then beam home images of possible planets and analysis of magnetic fields. Along its journey, the nanocrafts could supply worlds of information about asteroids it crosses and solar system exploration. While Breakthrough Starshot is not the first project to explore the idea of interstellar space travel, it far outweighs any previous attempt in terms of funding. In 2011 the US research agency DARPA and NASA provided $500,000 to seed the “100 Year Starship Project”. That doesn’t quite compare with the $10 million that has been allocated to Breakthrough Starshot.
Path to the stars
The research and engineering phase is expected to last a number of years. Following that, development of the ultimate mission to Alpha Centauri would require a budget comparable to the largest current scientific experiments. Once it is assembled and the technology matures, the cost of each launch is projected to fall to a few hundred thousand dollars.
I’m in, so when do we get the popcorn ready?
One of the great things about this initiative, aside from actually reaching interstellar space with a camera ready to send images to earth, is how the very development of this program is inviting the public to chime in with opinions and suggestions. The team is essentially crowd-sourcing solutions to the number of engineering and logistical challenges that remain before this is a reality. Transparency is important to the Breakthrough Starshot team, which is a great move, in my opinion. In about 25 years, we can finally microwave that popcorn as we await images of possible earth like planets from Alpha Centauri.