A team of scientists, technologists, and millionaire investors announced a plan Tuesday to send a "nanocraft," a spacecraft the size of a butterfly, to Alpha Centauri, the nearest star to Earth once you exclude the Sun.
As CNETreports, the Alpha Centauri Plan is backed by multi-millionaire investor Yuri Milner, who has pledged $100 million to the "Breakthrough Starshot" initiative. Other individuals behind the project, according to Ars Technica, include Facebook CEO Mark Zuckerberg; physicist Stephen Hawking; physicist Freeman Dyson; Ann Druyan, the woman behind COSMOS; Harvard astronomer Avi Loeb; and astronaut Mae Jemison. Former NASA researcher Pete Worden will serve as the lead scientist on the project.
Speaking Tuesday at a conference with project backers from atop the new World Trade Center building, physicist Stephen Hawking said that the problems that seem to prevent a mission to Alpha Centauri aren't so insurmountable when you consider how far we've come technologically.
"I believe what makes us unique is transcending our limits. Gravity pins us to the ground, but I just flew to America. How do we transcend these limits? With our minds and our machines. The limit that confronts us now is the great void between us and the stars. But now we can transcend it."
Alpha Centauri is the nearest star to the Earth, depending on your definitions. Of course, the actual nearest star to the Earth is the Sun, but the "Breakthrough Starshot" initiative is looking further away to our nearest stellar neighbor outside the solar system. That means the Alpha Centauri system: a three-star system consisting of Alpha Centauri A and Alpha Centauri B, which orbit each other, and a third star, a red dwarf known as Proxima Centauri, that cannot be seen by the human eye.
Alpha Centauri is about 4.37 light-years away, or about 25 trillion miles. The Sun, by comparison, is only about 93 million miles away. Light coming from the Sun reaches the Earth in about nine minutes. Traveling at the speed of light, which is impossible given our current understanding of the laws of physics, a spacecraft would reach Alpha Centauri in just over four years.
However, no current spacecraft are capable of approaching speeds even close to light speed. In fact, today's fastest spacecraft would require 30,000 years to reach Alpha Centauri. To put that in perspective, human beings in our current form only evolved around 200,000 years ago, and civilization as we know it has only existed for about 10,000 years.
The Alpha Centauri Project, however, hopes to overcome those barriers with the use of so-called "nano-spacecraft," which would be about the size of a smartphone.
As Ars Technica writer John Timmer explains, "The small spacecraft will be equipped with a light sail, and a phased array of lasers in the 100GW range will provide the sail with enough push to get the craft moving at roughly 20 percent the speed of light in just a matter of minutes."
At 20 percent of the speed of light, a spacecraft could reach Alpha Centauri in about 20 years, easily within the lifetimes of the people who launched it.
But why go to Alpha Centauri at all? As Stephen Hawking explains, human evolution may soon not be limited to just the planet Earth.
"Earth is a wonderful place, but it might not last forever. Sooner or later, we must look to the stars. Breakthrough Starshot is a very exciting first step on that journey."
As of this writing, there is no firm timetable on when a possible Alpha Centauri project may be launched.
[Image via Shutterstock/Triff]