Mysterious Object Headed Into Our Solar System Is Changing Shape, New Image Shows

"Even the most fleeting visitors can leave a lasting impact."

Astronomers have been racing to get a better look at 3I/ATLAS, a mysterious object screaming into our solar system from far beyond.

While there's a broad consensus among experts that the object is a comet, observations by four NASA telescopes have defied expectations, showing that it bears a much higher proportion of carbon dioxide gas than expected.

Now, as the BBC reports, new observations by the Gemini South telescope at Cerro Pachón in Chile have revealed that 3I/ATLAS' tail is growing longer, and that its chemical makeup resembles other comets in the solar system more than previous observations had suggested.

The data suggests that interstellar objects like 3I/ATLAS may share many of the evolutionary processes with more local and familiar comets, an intriguing conclusion that could have implications for our understanding of these lonely lumps of ice and dust.

Comets, sometimes referred to as "dirty snowballs," are icy bodies that release gases as they pass by the Sun, resulting in an archetypal tail shape made up of dust and ionized gas.

The closer they get to their perihelion, or the closest point to the Sun in their orbit, they become more active, sometimes releasing an epic plume.

In addition to the growing tail, an image of the comet taken by the Gemini telescope's Multi-Object Spectrograph (GMOS) also revealed a broad, glowing coma, which is a large atmosphere of gas and dust that surrounds a comet's nucleus.

Intriguingly, the team behind the latest image found that the dust and ice that make up the space rock resemble the materials that comprise other comets that formed within our solar system, suggesting interstellar objects like 3I/ATLAS may have similar origins.

"The primary objectives of the observations were to look at the colors of the comet, which provide clues to the composition and sizes of the dust particles in the coma, and to take spectra for a direct measure of the chemistry," said Gemini South program lead and University of Hawai‘i Institute for Astronomy astronomer Karen Meech in a statement.

"We were excited to see the growth of the tail, suggesting a change in the particles from the previous Gemini images, and we got our first glimpse of the chemistry from the spectrum," she added.

3I/ATLAS is expected to reach its perihelion in late October, bringing it tantalizingly close to Mars.

It's only the third interstellar object to have ever been confirmed, making it an exceedingly rare and exciting event.

"As 3I/ATLAS speeds back into the depths of interstellar space, this image is both a scientific milestone and a source of wonder," Meech said. "It reminds us that our Solar System is just one part of a vast and dynamic galaxy — and that even the most fleeting visitors can leave a lasting impact."

More on the object: Four Telescopes Confirm There's Something Deeply Strange About the Mysterious Object Headed Into the Solar System