A box of wilted passion fruit inspired Chinese scientists to invent a device that could be used to clean up space debris. Researchers from Fudan University in Shanghai and Tsinghua University in Beijing have developed a soft silicone ball with a bumpy texture resembling the wrinkled skin of dried passion fruit.
The deep wrinkles on the surface of the device can grab a variety of objects and could even be used to clean up tiny particles of space junk floating in orbit, scientists say. Xu Fan, a professor at Fudan University’s Department of Aeronautics and Astronautics, said the simple and nimble device could be manufactured in sizes ranging from millimeters to meters and deployed in inaccessible places.
“A robotic arm equipped with a sphere gripper could collect small space debris with high precision,” Xu said. “On Earth, it could pick up dangerous particles such as explosives.”
According to Nasa, there are about half a million pieces of marble-sized debris stuck in Earth’s orbit, while 100 million pieces as small as a pencil point orbit the planet. Even the smallest debris, such as paint specks from rockets, can damage spacecraft when they collide at extremely high speeds in low Earth orbit.
The idea came from a box of fruit left in the office. Xu’s colleague in Tsinghua called to say he had seen some interesting patterns in the withered produce, so the scientists started dehydrating the passion fruit to observe them. As they studied the ridges that deepened as the fruit dried, they were inspired to mimic models in the lab and put their observations to good use. They discovered that the pattern of the ridges could “grab” things, thanks to a property called “chirality”.