The rapid increase in brightness of the interstellar comet 3I/ATLAS as it approaches the Sun is puzzling researchers: these new features are added to others that cast doubt on the true nature of this mysterious cosmic body, which some experts even associate with an “interstellar spaceship”.
A popular visitor from another star system, the enigmatic comet 3I/ATLAS continues to surprise experts, now with a sudden burst of brightness when it reaches perihelion, or closest point to the Sun, behavior that is inconsistent with what has been observed in comets from the Solar System. The comet, identified on July 1, 2025 and listed as the third known interstellar object, showed a increasing brightness at a rate never seen before in similar bodies, passing near the royal star.
According to a study published on arXiv, the phenomenon was captured by solar satellites including SOHO, STEREO-A and GOES-19, given that the proximity of the Sun interfered with observations from Earth due to the glare created by the star. Researchers Qicheng Zhang of the Lowell Observatory and Carl Bottoms of the US Naval Research Laboratory used images from these probes and compared their signals with those of nearby stars, concluding that The flash of the comet was “accelerated” and of unprecedented magnitude.
Advantage of gas
In addition to the rapid and excessive increase in brightness, 3I/ATLAS It appeared in bluish color. This hue suggests that the luminosity was dominated by gaseous emissions, particularly from carbon molecules, rather than the reddish glow that cometary dust normally produces when reflecting sunlight. Therefore, scientists believe that the massive gas emission and unusually rich composition of volatile ices and carbon dioxide can partially explain the strange activity of the interstellar object.
In this sense, as Universe Today explains, images taken by large-aperture ground-based telescopes such as Gemini North have shown the comet as a kind of “space rainbow”: a sequence of colored fragments depicting various radiations and movements during observation. However, these images confirm that most of the comet’s brightness comes from gaseous emission lines, not just dust.
Help
A quick 3I/ATLAS illumination before perihelion. Qicheng Zhang and Carl Bottoms. arXiv (2025). DOI: https://doi.org/10.48550/arXiv.2510.25035
We are waiting for new observations
According to Phys.org, the phenomenon does not live up to expectations and requires additional observations as the comet moves away from the Sun and regains visibility from Earth. The coming months will allow us to study its composition and coma evolution with detailed spectroscopy, hoping that 3I/ATLAS will provide clues about the chemistry and history of other planetary systems. It should be remembered that its strange behavior led the famous American physicist Avi Loeb to suggest that the comet may actually be a piece or ship of extraterrestrial technology.
Meanwhile, because the 3I/ATLAS trajectory passed relatively close to the orbit of Mars, it facilitated observations from several space probes and telescopes. These data sets will be needed to determine whether the object is simply an ancient fingerprint of another star system, or whether its behavior also reveals physical processes, such as deposits of unstable ice or rare metals. which we have not been able to appreciate until today.
