Produced by: Tarun Mishra Designed by: Manoj Kumar
Scientists recently identified a comet, designated Comet A117uUD (A117uUD), traveling out of the solar system after a close encounter with Saturn. The comet was discovered on June 14, 2024, by the Asteroid Terrestrial-impact Last Alert System (ATLAS). Researchers utilized 142 observations to trace its orbital path, revealing a significant encounter with Saturn in 2022.
The meeting with Saturn, known for its bright rings and being the second-largest planet in the solar system, dramatically altered A117uUD’s orbit. This interaction placed the comet on a highly elliptical path, leading to its ejection from the solar system. The comet is now traveling into interstellar space at approximately 6,710 miles per hour (10,800 km/h), a speed roughly four and a half times that of an F-16 jet fighter.
This is only the second observed instance of a solar system comet being ejected due to a planetary encounter. The first recorded case was Comet C/1980 E1 (Bowell), which encountered Jupiter on December 9, 1980, and was subsequently launched out of the solar system.
The team behind the discovery noted in a paper published in the *Research Notes of the AAS*: “Our results show that the case of comet A117uUD is similar to that of C/1980 E1 (Bowell), disfavouring an extrasolar origin for A117uUD.” The observation of two such ejections within a span of 45 years suggests that these events might be more common than previously thought.
Initially, there was uncertainty about whether A117uUD originated from within our solar system. The team initially considered the possibility of an interstellar origin due to its hyperbolic orbit. However, further analysis confirmed that it is a solar system comet influenced by Saturn’s gravitational forces.
The first known interstellar object, the asteroid 1I/’Oumuamua, was discovered in 2017 and exhibited unusual characteristics, including a cigar-like shape and no cometary tail. This object, along with Comet 2I/Borisov discovered in 2019, provided valuable insights into interstellar visitors. Unlike A117uUD, these bodies entered and left the solar system from outside.
The encounter with Saturn altered A117uUD’s orbit so significantly that reconstructing its path before the encounter was not possible. As A117uUD continues its journey into the cosmos, it may one day intrigue astronomers from other civilizations, long after the humans who discovered it are gone.