According to the official website of sky & Telescope, a group of Canadian astronomical research teams have found that Jupiter, known as the “king of planets”, may have about 600 candidate satellites with a diameter of more than 800 meters! Most of them are distributed in wide and irregular retrograde orbits. And this new discovery has sparked a new debate: what is the size limit of an object that can be called a satellite? In the past 20 years, thanks to the development of large digital cameras, astronomers have discovered dozens of Jupiter’s small satellites. As early as 2003, the Carnegie Institute scientist Scott Shepard said that he estimated that the diameter of more than 1000 meters of Jupiter’s satellites, may reach about 100. < p > < p > this time, researchers from the University of British Columbia, Edward Ashton, Matthew bodooine and Brett gladman, jointly discovered nearly 50 small-sized crescent moons. Based on the results, they extrapolated and observed a space area of about one square degree. Finally, they concluded that there were nearly 600 smaller moons around Jupiter. < / P > < p > the team analyzed 60 images of the sky region near Jupiter from a 340 million pixel “megaprime” camera. The team arranged and combined these images 126 times, each of which is the possible speed and direction of Jupiter’s potential satellites. < / P > < p > using this method, the researchers found 52 objects with brightness below 25.7, which are about 800 meters in size. Among them, seven of the brighter ones are known irregular moons of Jupiter, and the rest are almost all retrograde ones, which move in the opposite direction of Jupiter’s rotation. < / P > < p > if this “pencil pencil beam” high sensitivity scanning of a square sky area can find 45 previously unknown satellites, the number of Jupiter’s moons with a size of more than 800 meters is estimated to be about 600. At present, the official number of Jupiter’s moons is only 79. < / P > < p > this new discovery has caused a debate on the definition of satellite size: what is the limit of the size of celestial bodies that can be called satellites? Is there a need for some kind of restriction? For the Canadian team, the discovery cannot be directly defined as “45 newly discovered Jupiter satellites”, let alone the 600 satellites extrapolated from it. According to Scott Shepard, scientists need to use large telescopes and spend some time precise orbit determination of these numerous small satellites before they can evaluate the scientific value of the findings. < p > < p > Jupiter is a large body in the solar system, so its attraction is not ordinary. Around it, there are millions of asteroids, which is the most crowded place in the solar system. At the same time, the number of Jupiter’s moons is relatively large, and the radius of these satellites ranges from several kilometers to several thousand kilometers. It is worth discussing whether the newly discovered celestial bodies can be regarded as the moons of Jupiter. If a very “mini” stone, as long as it revolves around the planet, even if its satellite, the number of satellites in the solar system will soar. Global Tech