While the spotlight is on Ukraine, news about an extraordinary space technology, dreamed up here in Montreal, has gone virtually unnoticed.
Sending astronauts to Mars, as NASA and China planned to do in the 1930s, presents significant logistical and technological challenges. Missions can only be launched to Mars every 26 months when our two planets are closest to each other. With current technology, NASA estimates that it will take astronauts around 500 days to reach the Red Planet. The transit time involves serious dangers for the crew exposed to cosmic rays, once out of the Earth’s magnetosphere.
A team of researchers from McGill University has designed a laser-thermal propulsion system that would reduce transit times to Mars to just 45 days! Until this study, it was thought that a rocket could only transit to Mars at such speeds with nuclear-powered engines.
The study was carried out by McGill graduate Emmanuel Duplay, along with associate professor Andrew Higgins and other researchers from the university’s Department of Mechanical Engineering. They propose a directed-energy propulsion system that uses terrestrial lasers to transmit energy to the spacecraft’s photovoltaic sensor to generate the electricity that propels it. The more powerful the laser, the greater the speed of the spacecraft. This technology could send satellites weighing 90kg from Earth to Mars in just three days!
The “laser thermal propulsion system” proposed by Emmanuel Duplay and his team is relatively simple: several 100 megawatt lasers, each ten meters in diameter, are fused into a beam directed towards the spacecraft already in orbit which picks it up thanks to an inflatable reflector.
Duplay explained to Universe Today that the laser flux from Earth directly heats the spacecraft’s thruster, much like a giant steam boiler. The laser energy is focused and directed to the spacecraft’s fuel compartment where the hydrogen creates a propelling force allowing the spacecraft to reach an incredible speed of 60,000 km/h. This allows it to accelerate rapidly while relatively close to Earth. When the spacecraft has absorbed enough energy, the reflector detaches and returns to Earth orbit for reuse.
There is still a lot of research to be done to make this technology operational. Very large lasers and hydrogen propulsion chambers must first be developed.
For the past few years, directed energy propulsion has been the subject of significant research. A concept for a laser-electric spacecraft is being studied by NASA in a joint study with the University of California, Santa Barbara and MIT.
Could Quebec, should it, play a major role in the development of this technology? We are a major research center in the fields of electricity, lasers and hydrogen: The Hydro-Québec Research Institute (IREQ), the Optics, Photonics and Laser Research Center (COPL ), Hydrogen Research Institute (IRH).
We also have cheap electrical energy to generate the electricity needed to propel such a system if terrestrial lasers could ever be installed in Quebec. Emmanuel Duplay should be invited to continue his research here in this area.