C/2024 L5 (ATLAS) is a comet that was discovered on 14 June 2024 as A117uUD by the Asteroid Terrestrial-impact Last Alert System (ATLAS), South Africa, Sutherland. It reached perihelion on 10 March 2025 at from the Sun.
It is the second known Solar System comet to become interstellar after experiencing a planetary encounter. C/1980 E1 (Bowell) reached a hyperbolic trajectory after an encounter with Jupiter on 9 December 1980. C/2024 L5 experienced a very close encounter at with Saturn on 24 January 2022. C/2024 L5 could be a former retrograde, inactive centaur. The receding velocity of C/2024 L5 when entering interstellar space will be 2.8 km/s, moving towards the constellation of Triangulum.
Orbit JPL Horizons shows an outbound eccentricity greater than 1 so it will leave the Solar System eventually as C/1980 E1 (Bowell) is doing, but prior to its flyby to Saturn its eccentricity was 0.88.
See also List of Solar System objects by greatest aphelion List of hyperbolic comets
References Solution using the Solar System Barycenter. Ephemeris Type:Elements and Center:@0 (To be outside planetary region, inbound epoch 1950 and outbound epoch 2100. Aphelia/orbital periods defined while in the planetary-region are misleading for knowing the long-term inbound/outbound solutions.)
External links
at the Minor Planet Center database