Recent discoveries about the comet 3I/ATLAS are exciting. New research suggests it might be erupting with “ice volcanoes.” As the comet approaches the sun, these icy jets seem to shoot off its surface. This phenomenon is known as cryovolcanism, and it offers a fresh perspective on the comet’s composition and behavior.
According to a study posted on arXiv, 3I/ATLAS shares similarities with icy bodies found in our solar system, particularly trans-Neptunian objects. This is surprising since it comes from another star system.
Josep Trigo-Rodríguez, the lead author of the study and a researcher at the Institute of Space Sciences in Spain, noted, “It’s remarkable that this comet formed in a distant planetary system yet shows similarities with objects in our own cosmic neighborhood.”
Since astronomers first spotted 3I/ATLAS in July, its origins have stirred curiosity. Many online speculations suggested it might be an alien spacecraft, but most scientists contend that it is a comet from an unknown star system. This comet is only the third such object recorded, presenting a unique chance to understand conditions around other stars.
As 3I/ATLAS moves through our solar system, researchers are racing to study it before it leaves later this year. They used the Joan Oró Telescope in Catalonia, Spain, to observe the comet as it neared perihelion, or its closest point to the sun, on October 29. When comets get close to stars, they heat up, causing ice to turn into gas, which is what astronomers study.
During their observations, the researchers noticed that 3I/ATLAS entered a vigorous sublimation phase about 235 million miles from the sun, brightening rapidly as jets of gas and dust revealed signs of cryovolcanism. Trigo-Rodríguez explained that cryovolcanoes typically emerge in bodies rich in ice. The intense heat from the sun likely melted some of this ice, enabling internal processes that led to the jet formations.
These jets are not only fascinating but also provide a window into the comet’s makeup. Trigo-Rodríguez believes they are driven by materials trapped within the comet being heated by the sun, leading to chemical reactions that eject vapor and particles into space.
To understand 3I/ATLAS better, researchers compared its properties with those of carbonaceous chondrites — primitive meteorites collected by NASA. They found that the comet shares traits with these ancient remnants, which likely played a role in forming our early solar system and possibly life on Earth.
While its exact size remains uncertain, estimates suggest it ranges from about 1,400 feet to 3.5 miles wide. Its mass could exceed 660 million tons, but it is confirmed that its path indicates it’s not bound to our sun, travelling at speeds too high to be captured by our solar system’s gravity. This interstellar visitor has spent billions of years traveling through space, which may have left it highly irradiated and hard to analyze.
Trigo-Rodríguez emphasizes that observing interstellar comets is essential. Not only do they represent potential hazards for Earth, but they also carry valuable information about chemistry in other parts of our galaxy. “They are like space capsules,” he said, filled with data waiting to be uncovered.
