Meteorites (陨石) can offer clues about what the early solar system was like. But finding them is far from difficult. Now, some scientists are turning to drones (无人机) and machine learning to help spot freshly fallen meteorites much more efficiently. “A team of six people on a meteorite-hunting expedition can search about 200,000 square meters per day,” says Seamus Anderson, a planetary scientist in Australia.
Around 2016, Anderson began toying with the concept of using drones to take pictures of the g round to look for meteorites. That idea blossomed into a Ph.D. project. In 2022, he and his colleagues reported their first successful recovery of a meteorite spotted with a drone. They’ve since found four more meteorites at a different site. Drone-based searches are much faster than the standard search way. “You’re going from about 300 days of human effort down to about a dozen or so,” he says.
Anderson and his workmates have used drones to search for meteorites in remote parts of Western Australia and South Australia. The team is tipped off about a fall site by networks of ground-based cameras that track meteoroids flashing through the Earth’s atmosphere. The researchers have to do a series of fun but difficult work before the hunt. They pack a four-wheel drive vehicle with drone and computer equipment, battery charging stations, generators, fuel, food, camping equipment, tables, chairs and much more. The drive to the fall site can take more than a day, often on rough or nonexistent roads. Anderson says, “You hope you don’t pop a tire.”
After arriving, the team flies its primary drone at an altitude of about 20 meters. Its camera takes an image of the ground once every second, and the scientists download the data every 40 minutes or so when the drone lands to receive fresh batteries. A typical day of flying can net over 10,000 images, which are then divided digitally into 100 million or so smaller sections. Those “tiles”, each 2 meters on a side, are fed into a machine learning algorithm (算法) that has been trained to recognize meteorites based on images of real land rocks which are spray-painted black.
12. Why do the scientists study meteorites?
A.To spot the planetary course. | B.To promote machine learning. |
C.To test the functions of drones. | D.To explore the past of solar system. |
13. What does Anderson say about drone-based searches in paragraph 2?
A.Their barriers. | B.Their causes. |
C.Their efficiency. | D.Their concept. |
14. Which words can best describe the preparations of the drone search for meteorites?
A.Fun and light. | B.Smooth and flexible. |
C.Difficult and unpleasant. | D.Complicated and tough. |
15. How does the drone process images?
A.By dividing them in half. | B.By storing them for analysis. |
C.By combining them into a picture. | D.By linking them with a digital printer. |