In anticipation of a future human mission to Mars, the European Space Agency has built and tested an electric ion thruster that could propel spacecraft and satellites using only air molecules.
Rocket motors are normally fueled by a mixture of gases containing argon, freon, nitrogen, and propane. In particular, the world's most powerful thrusters use a bipropellant mixture of monomethylhydrazine and dinitrogen tetroxide.
Combining these two substances is an intricate process because it ignites an explosion. Nonetheless, when used in fueling a thruster, the mixture helps produce around 2.7 tons of thrust and burn 9.8 tons of propellant in a span of 1,000 seconds. It has successfully propelled new satellites into low-earth orbit and has powered the Space Shuttle's orbital maneuvering system.
What ESA has recently created would not only make developing thrusters much safer for aeronautical engineers. It paves the way for longer missions while sparing astronauts from the risk of a potential explosion onboard.
The Use Of Atmospheric Molecules Instead Of Propellants
In lieu of explosive propellants, the electric rocket motor designed by the space agency's team gives spacecraft and satellites the ability to survive in other planets' atmospheres by taking in air molecules from the outer layer.
"This project began with a novel design to scoop up air molecules as propellant from the top of the Earth's atmosphere at around 200 km altitude with a typical speed of 7.8 km/s," says Louis Walpot, an ESA engineer involved in the thruster's development.
The original concept was proposed by the largest private space company in Italy, SITAEL. ESA then created a complete prototype and tested it in one of their facilities, where a low-earth orbit environment was simulated.
To provide the air fueling the propulsion system's intake and thruster, the team used a "particle flow generator" to artificially produce high-speed molecules.
These molecules are then collected by the intake built by Polish spacecraft manufacturer QuinteScience. In regular conditions, the air particles would simply bounce off the machine but the revolutionary intake compresses them before they are given electric charges.
Once these air molecules have been converted into charged ions, they are expelled to produce thrust.Throughout such process, the thruster made by SITAEL ensures better electric charging of incoming molecules to produce results that no existing propulsion system ever can.
To end their test, the team repeatedly ignited the rocket motor using xenon as an atmospheric propellant and each attempt was a success. This means the invention is ready to be developed for use in long-term space missions, including one that would take a man to Mars.
Space Agencies Partner To Send Man To Mars
In the past, the ultimate goal of space agencies around the world was to make it to the moon. Now that the Earth's lunar satellite has already been conquered, the next target is to send a human mission to Mars.
NASA is planning to send its Mars 2020 rover to investigate the red planet's resources such as oxygen while ESA's ExoMars Trace Gas Orbiter has finally entered Mars's orbit in search of methane.
