Rosetta Spacecraft Wore Bullet-Proof Vest in Space to Save Weight, Engineers Reveal
In a fascinating revelation, it has been disclosed that the Rosetta spacecraft, which made history by orbiting a comet, was sent into space wearing a bullet-proof vest. Engineers had to cut away its outer casing to save weight, making this an extraordinary feat of engineering. On the 20th anniversary of its launch, Ian Walters, the engineering manager for Rosetta at Airbus in Stevenage, shared this intriguing detail about the spacecraft’s journey.
The Rosetta spacecraft was launched on March 2, 2004, and it took a remarkable ten years to reach comet 67P/Churyumov-Gerasimenko. Upon arrival, it released a probe that landed on the comet’s surface. This mission was compared to a fly trying to land on a speeding bullet, highlighting the immense challenges faced by the scientists and engineers involved.
One of the major obstacles encountered during the mission was the spacecraft’s weight. To achieve orbit around the comet, Rosetta needed to carry a significant amount of fuel. This meant that every component of the spacecraft had to be as light as possible. Walters explained, “Mass was really, really critical and when we counted up everything, even the nuts, bolts, and washers, we realized, ‘This is going to be too heavy.’ We wouldn’t have even got to Mars, never mind the comet.”
To address this weight issue, the team had to come up with innovative solutions. They proposed 35 mass-reduction exercises to the European Space Agency (ESA), one of which involved cutting a hole in the top floor of the spacecraft. This left a propellant tank exposed, similar to cutting off a patient’s skull and leaving the brain exposed. However, this exposed tank posed a significant risk. If a high-speed micrometeorite were to hit it, it could cause an explosion or a catastrophic puncture, leading to fuel leakage.
To mitigate this risk, the engineers decided to cover the hole with a Kevlar-like material, essentially creating a bullet-proof vest for the spacecraft. Walters described it as a “skull-cap” that was launched with the spacecraft. Despite the constant state of panic and doubt, this ingenious solution proved successful in protecting the exposed tank.
The journey to the comet was no less challenging. The comet was moving at speeds far greater than any spaceship leaving Earth could achieve. To overcome this, Rosetta had to utilize the gravitational pull of Earth and Mars as a slingshot, allowing it to pick up acceleration. In July 2011, when the spacecraft reached the crucial speed, it was put into deep-space hibernation for the coldest and most distant leg of the journey. It traveled a staggering 497 million miles from the Sun, reaching close to the orbit of Jupiter as the comet headed into the outer solar system.
After awakening from its hibernation in January 2014, Rosetta finally reached the comet on August 6, 2014. The lander Philae was set down on November 12, 2014. However, during landing, Philae’s harpoons failed to fire, causing it to bounce three times before settling under the shadow of a cliff. This unfortunate landing spot meant that its solar panels couldn’t gather enough energy. Although Philae managed to send back some data and images of its landing site, it ran out of power on November 14 and ceased communication with Rosetta.
In a controlled crash in 2016, Rosetta made its final descent onto the comet. This marked the end of an extraordinary mission that provided invaluable insights into comets and their composition.
The Rosetta spacecraft’s journey to comet 67P/Churyumov-Gerasimenko was a testament to human ingenuity and determination. Engineers had to overcome weight constraints by cutting away parts of the spacecraft, leaving it vulnerable. However, their solution of a bullet-proof vest made from a Kevlar-like material protected the exposed tank, ensuring the success of the mission. This groundbreaking mission broadened our understanding of comets and their role in the solar system.