“Sounds like science-fiction, but I believe it can be realized,” said Li Mingtao, a researcher at the National Space Science Center under the Chinese Academy of Sciences who, along with a group of Chinese scientists, are mulling a bold plan to capture a small near-Earth asteroid, more than 100 million km away, about 6.4 meters in diameter, that weighs several hundred tons.
The process could start with a spacecraft carrying a huge bag to wrap a small asteroid and push it back over the Earth. Then it would unfold a heat shield to reduce the velocity of the asteroid when it enters the Earth’s atmosphere, and control it to safely land in a no-human zone, Li explained.
Li is working with space engineers at the Qian Xuesen Laboratory of Space Technology, under the China Aerospace Science and Technology Corporation, to draw up a plan for a satellite constellation on the heliocentric Venus-like orbit. The satellites will be used to search for and analyze near-Earth small celestial bodies with a diameter around 10 meters. The hardest challenge might be the control of the asteroid after it enters the Earth’s atmosphere. They must design a heat shield, and drop the speed of the asteroid from 12.5 km per second to about 140 meters per second before it touches down at a designated area.
The asteroid’s main components are still not clear, and need more observation and analysis to determine. Li calculated the proper time to launch an asteroid catcher would be 2029, and it could be brought back to Earth in 2034.
NASA is reportedly planning to launch a spacecraft in 2022, which is due to arrive at an asteroid named Psyche in 2026. More than 95 percent of Psyche appears to be made of iron, nickel, and other metals such as gold, platinum and copper. “Space mining might become a new engine for the global economy,” said Li.
So far, the United States and Japan have landed probes on asteroids. Japan has brought back a sample. After sending a probe to Mars in 2020, China plans to explore asteroids and even land on one to conduct scientific research.
“Unlike missions to bring samples back, we aim to bring back a whole asteroid weighing several hundred tons, which could turn asteroids with a potential threat to Earth into usable resources,” said Li.
After joining the National Space Science Center, Li took part in China’s space science programs, and helped design the trajectory for the Chang’e-2 probe to the second Lagrange point of the Sun-Earth system. The probe is China’s farthest flying spacecraft.
The Daily Galaxy via Xinhuanet