Interstellar travel soon a reality Stephen Hawking insists

Travelling to other star systems, something humans will eventually have to do if we want to prevail as a species, will most likely soon be a reality, eminent theoretical physicist Professor Stephen Hawking announced yesterday. Interstellar travel means travelling to other star systems – leaving our solar system and entering another one with planets orbiting another star.

Prof. Hawking says he is supporting a project to send ultra-tiny spacecraft – called nanocrafts – to another star system, which will hopefully occur within one generation. These chip-sized ‘starships’ will travel trillions of miles, significantly further than anything we have sent out into space so far.

The $100 million research programme – called Breakthrough Starshot – to develop miniature starships was launched by Yuri Milner, a Russian billionaire entrepreneur, venture capitalist and physicist, whose parents named him after the first man in space, Russian cosmonaut Yuri Alekseyevich Gagarin. A venture capitalist is somebody who invests in new ideas and startup companies.

Interstellar travel using light powerAn array of several ‘light beamers’ would shoot laser beams into space. The photons (light particles) would hit the wafer-thin sails of the nanocraft and accelerate it to 100 million miles per hour. (Image: Breakthrough Starshot Video)

Breakthrough Starshot is supported by Mark Zuckerberg, co-founder and current boss of social networking website Facebook.

Interstellar travel – a dream come true?

Scientists and lay people across the world have long dreamed of interstellar travel, however, considerable challenges remain, the main one being the enormous distances involved. With our current technology, we are looking at tens of thousands of years to leave our Solar System and entering another one.

In an interview with BBC News, Prof. Hawking said interstellar travel within realistic time scales may come sooner than many people realise.

Regarding the long-term survival of human beings as a species, Prof. Hawking said:

“If we are to survive as a species we must ultimately spread out to the stars. Astronomers believe that there is a reasonable chance of an Earth-like planet orbiting one of the stars in the Alpha Centauri system.”

“But we will know more in the next two decades from ground based and space based telescopes. Technological developments in the last two decades and the future make it possible in principle within a generation.”

Professor Stephen HawkingProf. Stephen Hawking says we need to move into space and occupy other planets if we want to secure the long-term survival of the human race. Earth is a fragile planet which is vulnerable to supernova explosions, asteroid impacts and other catastrophes that could destroy us. (Image:

Prof. Hawking is supporting a project by the Breakthrough Initiative, part of the Breakthrough Foundation, a private, non-profit organization supported by Mr. Milner and Mark Zuckerberg among others, which funds scientific research projects which governments deem too ambitious to back.

According to Breakthrough Initiatives, nanocrafts are ultra-small robotic spacecrafts comprising two main parts:

StarChip: Moore’s law has allowed a dramatic decrease in the size of microelectronic components. This creates the possibility of a gram-scale wafer, carrying cameras, photon thrusters, power supply, navigation and communication equipment, and constituting a fully functional space probe.”

Lightsail: Advances in nanotechnology are producing increasingly thin and light-weight metamaterials, promising to enable the fabrication of meter-scale sails no more than a few hundred atoms thick and at gram-scale mass.”

Specialist group to determine feasibility of project

The Breakthrough Prize Foundation has gathered an expert group of scientists to determine whether it will be possible to create spaceships that can travel to another star system and send information back to Earth – within one generation.

Yuri MilnerYuri Borisovich (Bentsionovich) Milner was born in Moscow in 1961. He founded Digital Sky Technologies (DST Global) and has a net worth of $2.9 billion, according to Forbes. He is an investor in Twitter, Facebook, Zynga,  Flipkart, Spotify, Planet Labs, ZocDoc, Alibaba, Groupon,, Xiaomi, OlaCabs, Wish and several other businesses. (Image:

The nearest star system (solar system outside our Solar System) is 25 trillion miles (40 trillion km) from here – 4.37 light years. It would take more than thirty thousand years to get there using our current technology. That means that if a spaceship had been sent during the early part of the Early Stone Age, it would be arriving there about now.

According to the expert group, we might be able to create spacecraft that could reduce the journey to just thirty years, with a little more research and development.

Chairman of the Breakthrough Prize Foundation, Dr. Pete Worden, who is leading this project, said:

“I’d have said that even a few years ago travel to another star at that kind of speed would not be possible. But the expert group figured out that because of developments in technology there appears to be a concept that appears to work.”

Dr. Worden is former director of NASA’s Ames Research Center in California.

Alpha CentauriAlpha Centauri is the closest star system to our Solar System at 4.37 light years. It consists of three stars: the pair Alpha Centauri A and Alpha Centauri B and a small and faint red dwarf, Alpha Centauri C, also known as Proxima Centauri, that may be gravitationally bound to the other two. The aim would be to send the nanocraft into Alpha Centauri. (Image: Wikipedia)

Electronic chip sized spacecraft with sails

Scientists aim to create tiny spacecraft – about the size of an electronic chip. Thousands of these mini spacecraft would be launched into Earth’s orbit. Each one would have a ‘solar sail’, which would be pushed along by light rather than the wind.

A huge laser on Earth would give each mini spacecraft a powerful push, sending them into deep space – eventually, they would travel at one-fifth of the speed of light, or 100 million miles per hour.

The concept may once have sounded like science fiction, but Mr. Milner believes that it is technologically possible to create these silicon-chip-sized spacecraft and arrive at another star within our lifetime.

Mr. Milner said:

“The human story is one of great leaps. Fifty-five years ago today, Yuri Gagarin became the first human in space. Today, we are preparing for the next great leap – to the stars.”

Many challenges to overcome

There are still several challenges we need to overcome before we even consider starting on seeing how to build these interstellar spaceships. We will need to create ultra-high-tech miniaturizing cameras, sensors and other instruments that fit on a chip, plus a solar sail that is strong enough to withstand being blasted by a super-powerful laser for several minutes.

We will also need to develop technology that can send images and data of the new star system back to Earth.

Prof. Sir Martin Sweeting, founder and executive chairman of Surrey Satellite Technology Ltd (SSTL), a spin-off from the University of Surrey, who founded a company in the 1980s that considerably reduced the size and cost of satellites, told BBC News:

“A lot of what we did in the 1980s was considered very wacky but now small satellites are considered all the fashion. This [interstellar project] is currently a wacky sounding idea but technologies have moved on and now it is not wacky it’s just difficult.”

Prof. Andrew Coates, who works at th University College London’ Mullard Space Science Laboratory, said of the project:

“There would be significant difficulties to solve such as ruggedisation for the space radiation and dust environment, instrument sensitivity, interaction of the high power accelerating laser with the Earth’s atmosphere, spacecraft stabilisation and power provision.”

Regarding the technology required for Breakthrough Starshot, Breakthrough Initiatives said:

“The key elements of the proposed system design are based on technology either already available or likely to be attainable in the near future under reasonable assumptions.”

“The proposed light propulsion system is on a scale significantly exceeding any currently operational analog. The very nature of the project calls for global co-operation and support.”

“But it is a concept worth looking at to see if we could really reach another star system within a human lifetime.”

Prof. Hawking believes humankind’s long-term future looks extremely uncertain if we keep all our eggs in one fragile basket. “Life on Earth faces dangers from astronomical events like asteroids or supernovas,” he told the BBC.

The following individuals are members of the Breakthrough Starshot Board

Professor Stephen Hawking, Director of Research at the Centre for Theoretical Cosmology within the University of Cambridge; Dennis Stanton Avery and Sally Tsui Wong-Avery Director of Research at the University of Cambridge; Yuri Milner, Founder of DST Global; and Mark Zuckerberg, Founder and CEO, Facebook.

Interesting related article: “Alien contact could destroy us warns Stephen Hawking.”

Video – Sending nanocraft to other star systems

In this Breakthrough Starshot video animation, you can see the array of light-beamers on Earth. When the nanocraft is in orbit, the beamers blast it with laser beams which hit the wafer-thin sails and send the tiny craft towards another star system at one-fifth the speed of light.