Humans are in dire danger, and in efforts to explore other worlds in lieu of Earth, it may be time to ride on a beam of light through the power of Einstein’s theory of relativity.

This is another bold pronouncement from renowned physicist Stephen Hawking, which he made at an arts and science festival in Trondheim, Norway, last June 20. Hawking also called for leading countries to send astronauts to the moon by 2020 as well as build a base there in three decades’ time and send humans to Mars by 2025.

Space Colonization: Time To Race To The Stars?

At Starmus Festival, where he also sits on the advisory board, Hawking said that in spite of human ability to prove the universe’s farthest reaches right at the comfort of home, humanity should not be satisfied with the approach to guarantee its future survival as a species.

“Shouldn’t we be content to be cosmic sloths, enjoying the universe from the comfort of Earth? The answer is, no. The Earth is under threat from so many areas that it is difficult for me to be positive,” he said in his speech.

The scientist warned against the growing threats of overpopulation in the face of climate change, as well as the extinction of many animal species and dwindling physical resources.

For Hawking, it’s time to push our boundaries and explore other worlds, namely in the vicinity of Proxima Centauri located around 4.5 light-years from us. It’s our nearest stellar neighbor and circled by a planet dubbed Proxima Centauri b, which is potentially Earth-like in a number of ways.

At current capabilities, the travel to the exoplanet would last 3 million years. Thus to realize this mission, new technology is necessary, Hawking asserted.

“To go faster would require a much higher exhaust speed than chemical rockets can provide — that of light itself,” he said, citing a potent beam of light to propel the spaceship forward.

Nuclear fusion, according to Hawking, could give off 1 percent of the space vehicle’s mass energy, accelerating it to one-tenth of the speed of light. Achieving greater speeds entails matter-antimatter annihilation, which would release so much energy, although it should be noted that technology exploiting this is yet to materialize.

Hawking and Russian billionaire Yuri Milner founded Breakthrough Starshot, a $100 million research to send iPhone-sized, robot-like probes to nearby stars in one generation to embark on interstellar travel.

The team is devising an early prototype: a tiny centimeters-wide probe attached to a small light sail. A thousand of these so-called StarChips and sails will be sent into the void, with lasers to form a potent light beam to propel the sails with gigawatts of power.

The probes would likely reach the stellar system in just two decades moving at one-fifth the speed of light. It would transmit images of potential planets on another beam.

The Moon And Mars

Of course, the easiest targets are still those closest to Earth, namely its moon and planet Mars. The moon, however, is small, boasts of no liquid water, and lacks a magnetic field needed to protect against radiation. Mars too may have ancient liquid water and atmosphere but not anymore.

NASA has shelved plans to return to the moon, instead eyeing a human mission to Mars by the 2030s. As BBC pointed out, though, it would likely be involved if other space agencies and organizations start to collaborate on building a lunar base.

“I am convinced that humans need to leave Earth,” Hawking said, underscoring the need to spread out as the only likely savior of humans from themselves.

And he called for different nations to come together in this common goal, firm in his belief that the planet would either be hit by an asteroid once again or will be engulfed by its own sun.

“To leave Earth demands a concerted global approach, everyone should join in. We need to rekindle the excitement of the early days of space travel in the sixties.”