A 7-Billion-Year-Old Visitor Just Woke Up: Comet Atlas Is Doing Things No Comet Has Ever Done Before

In July 2025, the astronomical community was abuzz with excitement as the third interstellar object, dubbed Comet Atlas, was discovered.

This ancient comet, believed to be over 7 billion years old, has captivated scientists and space enthusiasts alike, providing a unique opportunity to glimpse into the early history of our galaxy.

As Atlas recently completed its closest approach to the sun, known as perihelion, new discoveries have emerged that challenge our understanding of comets and their role in the cosmos.

Comet Atlas has been on a remarkable journey through the solar system, and its recent perihelion on October 29, 2025, marked a significant milestone.

Positioned about 220 million kilometers from the sun—roughly the distance from the Earth to the sun—Atlas was unfortunately obscured from view by our star.

Astronomers had to rely on space-based observatories like SOHO and GOES-19 to monitor its progress during this crucial period.

As Atlas reemerges from behind the sun, researchers are eager to study its unique characteristics and the changes it underwent during its encounter.

The comet’s age makes it a cosmic time capsule, potentially holding invaluable insights into the formation of our solar system and the universe at large.

One of the most astonishing discoveries came just before perihelion when Comet Atlas experienced an unprecedented surge in brightness.

Between October 20 and 25, the comet became significantly more luminous, shining brighter than ever before.

Observations from Mars revealed a breathtaking view of this spectacle, as Atlas’s brightness increased at an extraordinary rate, unlike typical comets that gradually glow as their ice sublimates.

This sudden brightness spike followed an inverse power of seven, suggesting a unique phenomenon occurring on the comet’s surface.

Researchers are still investigating the cause of this dramatic change, but it hints at the active processes happening as Atlas approaches the sun.

In addition to its brightness, Atlas exhibited a puzzling color shift, appearing bluer than the sun itself.

This change indicates the presence of volatile molecules such as cyanide or ammonia, which emit bright visible light.

The blue glow outshines the red light reflected by dust, giving the comet its distinct hue.

This was not the first color change observed; earlier, Atlas had glowed with a greenish tint, the cause of which remains unknown.

These observations underscore the comet’s high activity level, releasing materials at a rate many times greater than most comets in our solar system.

The dynamic nature of Atlas raises intriguing questions about its composition and the processes at play.

Recent data from the James Webb Space Telescope has revealed that Atlas’s surface has endured extreme radiation throughout its long journey.

This exposure has resulted in a dense ancient crust, estimated to be 15 to 20 meters thick, which serves as a geological record of the universe.

This crust preserves traces of every impact and cosmic ray that the comet has encountered, offering a glimpse into the conditions of the early solar system.

If humans were to land on Atlas, they would find not a dead block of ice but a living witness to the universe’s history.

The crust may hold the key to understanding how the raw materials of the cosmos evolved and could even provide clues about the origins of life elsewhere in the universe.

One of the most significant revelations concerns the unusually high levels of carbon dioxide detected on Atlas.

Initially, scientists were puzzled by the elevated carbon dioxide levels, but new infrared data suggests that this abundance is a result of the long period of cosmic radiation exposure.

Over billions of years, carbon monoxide on the comet’s surface has gradually transformed into carbon dioxide, enriching the outer crust with this distinct chemical signature.

This finding alters our understanding of cometary chemistry, suggesting that the gases and ices released from comets are not pristine remnants of the early universe but materials that have undergone chemical transformations due to cosmic radiation.

This insight challenges previous assumptions about the nature of cometary materials and their role in the solar system’s evolution.

The significance of interstellar comets like Atlas extends beyond their chemical composition.

Recent studies propose that these wandering icy bodies could play a crucial role in the formation of planets.

Traditionally, scientists believed that planets form from collisions among dust grains and rocky fragments around young stars.

However, this process encounters a barrier known as the “meter barrier,” where particles larger than a meter tend to bounce off one another rather than stick together.

New theories suggest that interstellar comets might provide a breakthrough.

When these ancient objects pass near a young star surrounded by a protostellar disk, their gravitational influence could capture them, allowing them to act as seed cores that attract surrounding dust and pebbles.

This process could facilitate the rapid growth of planetary embryos, bypassing the meter barrier and enabling the formation of planets.

Comet Atlas is more than just a celestial object; it is a time capsule preserving the complex chemical history of the universe.

Each observation reveals new clues about how cosmic matter has evolved over time.

As scientists continue to study Atlas, they are racing against the clock before it disappears into the depths of space, possibly never to be seen again.

Following its perihelion, Atlas has been imaged by various observatories, including the LOL Observatory’s Discovery Telescope.

Amateur astronomers can now catch glimpses of the comet as it draws closer to Earth, providing a rare opportunity to witness a visitor from beyond our solar neighborhood.

As Atlas continues its journey, scientists are eager to gather as much data as possible.

The upcoming December 19 close approach to Earth will provide a unique opportunity for high-resolution imaging and analysis of the comet’s nucleus, gas emissions, and dust released as it heats up.

Missions like the Clipper are even expected to collect particles from Atlas’s plasma tail for laboratory analysis, potentially yielding invaluable insights into the origins of comets and their role in delivering water and organic molecules to young planets.

In conclusion, Comet Atlas is not just another frozen rock passing through our solar system; it is a remarkable witness to the universe’s ancient history.

Its unpredictable behavior and unique characteristics challenge our understanding of comets and their formation.

As scientists continue to study this interstellar traveler, they are uncovering secrets that may reshape our understanding of planetary origins and the interconnectedness of the cosmos.