Javier Licandro, an astronomer at the Institute of Astrophysics of the Canary Islands (IAC), has clarified the nature of the interstellar object 3I/Atlas, countering speculation about its origin. Despite claims from notable figures like Avi Loeb from Harvard suggesting the object could be an extraterrestrial spacecraft, Licandro firmly states, “All available data indicates it behaves like a comet; it is a comet, a natural object. It is neither a spaceship nor anything resembling one.”
Since its discovery, 3I/Atlas, which originated outside the solar system, has sparked considerable interest. Its close approach to Earth and the Sun provides scientists with a unique opportunity to gather valuable data about both our solar system and beyond. Licandro emphasizes that this comet is particularly significant because it did not form around the Sun but rather around another star, which supports the idea that comet-like objects can form around various stars throughout the universe.
The formation of comets typically occurs during the planet formation process, often in colder regions away from their stars. “Comets are essentially blocks of ice,” Licandro explains. As they evolve, many comets integrate into surrounding planets, while those that do not remain as wandering bodies between stars. “3I/Atlas is one of the millions of comets that have escaped their original stars and happened to cross paths with the Sun and Earth,” he added.
This object marks the third interstellar object observed and tracked by humanity, and it is the second comet of this nature. The first, Oumuamua, left scientists puzzled due to its brief visibility. The second was 2I/Borisov, which was more definitively classified as a comet.
Fortunately, the scientific community will have the chance to observe 3I/Atlas for several more months, likely until February. This timeframe is crucial for extracting as much information as possible before it escapes the solar system on a nearly straight trajectory, never to return.
Licandro notes some of the findings regarding 3I/Atlas that have already been established, including its comet-like behavior and its icy composition, similar to certain trans-Neptunian objects in the solar system. These trans-Neptunian objects, which reside beyond Neptune, have been shown to contain high levels of carbon dioxide on their surfaces. However, this carbon dioxide dissipates rapidly as they approach the Sun.
The passage of 3I/Atlas is particularly valuable because it is not just a comet from outside the solar system; it is also rich in carbon dioxide, allowing scientists to observe how an object with significant carbon dioxide behaves as it approaches the Sun for the first time. Currently, the comet travels at approximately 68 kilometers per second and has a nucleus measuring between 10 and 30 kilometers. It reached its closest point to Earth recently without posing any threat to the planet or its inhabitants.
Licandro emphasizes that observing 3I/Atlas is not comparable to watching more prominent comets that are visible to the naked eye and typically exhibit greater brightness and spectacle. He recalls that the object was discovered by the Asteroid Terrestrial-impact Last Alert System (Atlas) network in Chile in early July. The Atlas Teide telescope, installed in January on the island of Tenerife, is currently operational and actively discovering asteroids, supernovae, and other interesting astronomical entities. “Let”s see when our interstellar object falls,” he quipped.
