An expired 2.9 tonne (approximately 2630 kg) battery comes to Earth from the International Space Station. The batteries are thrown out by the space station’s long robotic arms. At an altitude of about 265 miles above the ground, the discharged batteries do not immediately reach the ground. Years later, after orbiting in the atmosphere close to Earth, they fall to the ground and disappear.
The release of the batteries comes after NASA completed an upgrade of the batteries that will power the International Space Station. 48 expired nickel hydrogen batteries have been replaced with 24 lithium ion batteries. The battery replacement process, which began in 2016, took about four years. The last batteries were delivered to the ISS in 2020.
NASA had earlier decided not to destroy the batteries by throwing them to the ground. The plan was to bring the Japanese H-II transfer vehicle (HTV) to Earth. But the failure of the 2018 Soyuz launch misled NASA. Spacewalks outside the ISS had to be rearranged for repairs and so on. With this, it was decided to drop the batteries from the space station.
At 2,630 kilograms, these batteries are the largest object to be ejected from a space station in terms of weight. In 2007, the ammonia servicing system tank was removed from the ISS. It is also the heaviest object previously ejected by the space station.
But these batteries are not the biggest object falling from space to Earth. This is the location of China’s Long March 5B rocket. The rocket was launched on May 11, 2020. What made it special was that it had only one stage compared to other rockets. So six days after the mission was completed, the rocket lost control and crashed into the ground. The rocket is estimated to weigh about 21 tons (approximately 19,000 kilograms). The rocket landed in the Atlantic Ocean, thus avoiding accidents.
English summary: 2.9 ton space station batteries fall to Earth from 426 km