Mars is likely the next extraterrestrial target for humans to visit in the coming decades, but such a journey would take around nine months to arrive using standard chemical rockets. Now, a NASA physicist has proposed a revolutionary laser propulsion system that would complete the trip in just 30 days. Refinements of this theory suggest the time for a journey to the red planet could be reduced to just three days – or perhaps a mere 30 minutes.
Chemical propulsion systems currently in use are dependent on the relative positions of Earth and Mars to deliver payloads in a reasonable amount of time. Still, such a manned mission would require 260 days to shuttle humans to our nearest planetary neighbor.
A proposal describing a method to bring a payload to Mars in just half an hour was described at NASA's Innovative Advanced Concepts (NIAC) conference held in October 2015.
Such a craft would be launched into space where a large solar sail would be deployed. An immensely powerful laser orbiting Earth would fire a beam directly at the sail, propelling the vehicle. With little resistance, such a craft could quickly accelerate to a significant portion of the speed of light. Theoretically, a vehicle using this design could accelerate to 45,000 miles per second (25 percent of the speed of light) in just a few minutes.
"We propose a roadmap to a program that will lead to sending relativistic probes to the nearest stars and will open up a vast array of possibilities of flight both within our solar system and far beyond... These systems can be propelled to speeds currently unimaginable with existing propulsion technologies. To do so requires a fundamental change in our thinking of both propulsion and in many cases what a spacecraft is," Philip Lubin, a physics professor at the University of California Santa Barbara, wrote.
Using light to push a spacecraft along to its target is not the only futuristic propulsion system being devised. Researcher Ryan Weed is currently developing a system of rockets powered by antimatter that could send spacecraft to Mars in just a few weeks.
A variety of nuclear-powered spacecraft have been proposed over the last few decades, including some designs that would utilize the power of atomic weapons to propel humans and cargo deep into space at speeds far beyond that which is currently possible.
The Nuclear Engine for Rocket Vehicle Application (Nerva) was a plan devised decades ago, which would have utilized an atomic-powered engine to ferry human space travelers to Mars. This plan was shelved by the U.S. Government in 1972, and was never revived.
Orion was another early design for futuristic spacecraft, utilizing nuclear weapons to propel the vehicle.
Project Daedalus was also once proposed as a means of carrying humans to other planets in our solar system and beyond. Researchers envisioned the craft reaching a top speed of 12 percent of the speed of light, driven by engines employing nuclear fusion.
Unlike these earlier designed, the new proposal delivered by Lubin would not require the spacecraft to carry fuel, greatly reducing the mass of the vehicle as well as cost.
Details of how laser propulsion could be used to reach Mars in as little as 30 minutes was published in the Journal of the British Interplanetary Society.