NASA engineers plan to deliver the samples collected from Mars to Earth with a special vehicle. And that vehicle will be the Mars Sample Return Orbital.
Naturally, the vehicle needs to be protected against meteorites during its return journey to Earth. Therefore, the entire vehicle will be covered with an anti-meteor shield material.
But how durable is this material? NASA is also curious about this and is running various tests. The most interesting of these tests is undoubtedly firing micro-bullets into the vehicle.
During tests at NASA’s White Sands Test Facility near Las Cruces, New Mexico, the shield has to withstand the impact of bullets at such high velocities. If a plane were to travel that fast, it could travel from New York to San Francisco in less than 5 minutes, according to White Sands test engineer Dennis Garcia.
But even these speeds aren’t as fast as meteoroids and pieces of space debris orbiting through space, so engineers have to use computer models to simulate real speeds, which can reach 80 kilometers per second. At these speeds, “even dust can damage a spacecraft,” says Bruno Sarli, an engineer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who oversaw the tests.
The Remote Hypervelocity Test Laboratory, where tests are conducted, has been used by NASA since the space shuttle era and enables engineers to develop materials that protect the International Space Station, commercial crew vehicles and space cargo ships from the effects of debris and rock fragments in space.
How are micro-projectiles fired?
The weapon used to fire space-like micro-projectiles into the material used in the Mars vehicle has two stages. The first of these stages uses conventional gunpowder to propel a projectile. The second stage gives the bullet extra power by pushing highly compressed hydrogen gas into a smaller tube like an automobile piston. According to the researchers’ statement, the pressure in this weapon is so high that if it explodes, it could destroy the entire building.
Sarli said the engineers discovered that instead of relying on a thick block of metal to protect from bullets, a shield made up of multiple thin layers provides better protection.
The Mars Sample Return Orbiter, to be built jointly by NASA and the European Space Agency (ESA), will bring back to Earth the precious samples of Martian rock that NASA’s Perseverance rover is currently collecting on the planet’s surface. The mission will be the first of its kind and will allow scientists, for the first time, to hold onto rocks newly mined from another planet.
Although Martian meteorites sometimes fall to Earth, these rocks have structures altered by the harsh environment and radiation during their journey through space, which can take millions or billions of years. Also, when Martian meteorites hit our planet, they are contaminated by Earth life, making it difficult to look for signs of Red Planet organisms.