Comet C/2023 A3 Tsuchinshan-ATLAS on Saturday reached its closest distance to the Earth, only 0.472 astronomical units away from the Earth which equals to about 43.9 million kilometers, said an expert from the Beijing Planetarium.
The expert also said that it will be the best observation time from now until October 26.
The comet, with a yellow tail, was first observed by the near-Earth object telescope of the Purple Mountain Observatory of the Chinese Academy of Sciences on Jan 9, 2023.
Its intense brightness has attracted attention of astronomy experts and enthusiasts around the world.
"The reason why this comet has attracted wide attention is that it is indeed quite bright. Relatively speaking, it is bright enough to be easily seen by the naked eye," said Cao Jun, an associate researcher at the Beijing Planetarium.
The comet is widely known among the public as one that will appear again after more than 60,000 years, but Cao believes that this is just a good wish, and it is more likely that the comet will never return.
According to the law of planetary motion proposed by German astronomer Johannes Kepler, all planets orbit the Sun in an ellipse, with the Sun at one focus, under which, theoretically, comet C/2023 A3 will return to its current position after 60,000 to 70,000 years. But later research found that this is actually a special case, which is applicable for planets or periodic comets.
For other celestial bodies in the solar system, their orbits are conic curves, that are ellipses, parabolas or hyperbolas. The known trajectory of comet C/2023 A3 Tsuchinshan-ATLAS indicates that its elliptical orbit is too oblate.
"It has become a parabola, which is open at both ends. It means that if a comet moves on such a parabolic orbit, it will not come back after approaching and then moving away. So, from my perspective, I don't expect to see it again after 60,000 or 70,000 years," said Cao.
Meanwhile, after a comet moves away from the Sun, it will be disturbed by the gravity of other celestial bodies. As long as such gravity has enough energy, the comet will no longer be attracted to the vicinity of the Sun.
Comet C/2023 A3 reaches closest to Earth Saturday
Comet C/2023 A3 reaches closest to Earth Saturday
Comet C/2023 A3 reaches closest to Earth Saturday
