A historic discovery by South Africa’s MeerKAT radio telescope has transformed scientific understanding of the interstellar comet 31/ATLAS, marking the first time a radio signal has ever been detected from an object originating outside our solar system. 

This fast-moving wanderer, officially known as 3I/ATLAS, had already captivated astronomers worldwide—and MeerKAT’s breakthrough has only intensified the excitement.

A New Era in Interstellar Exploration

The signal detection came just days before the comet’s closest approach to the Sun. According to astronomers, MeerKAT identified two radio frequencies—1,665 and 1,667 MHz—corresponding to hydroxyl (OH) radicals produced when sunlight breaks apart water molecules.

“This is the first radio whisper from an interstellar object—we’re listening to a traveler that began its journey billions of years ago,” one researcher noted.

MeerKAT’s achievement followed its recent detection of 30 new radio transient pulsars, underscoring its expanding role in deep-space discovery.

Relevant links:

Live 3I/ATLAS tracking: New York Post — https://nypost.com/2025/11/16/science/heres-how-to-watch-a-livestream-of-31-atlas-moving-away-from-the-sun/

NASA to release best quality images of Manhattan-sized interstellar object 3I/ATLAS next week | New York Post

3I ATLAS News | 3I/ATLAS Trajectory Tracking | ATLAS 3I | 31 ATLAS Update | Star Walk

Rare Visitor from Beyond the Solar System

3I/ATLAS was first identified on July 1, 2025, by Chile’s ATLAS survey system. Hurtling at roughly 130,000 mph, it immediately stood out due to its hyperbolic trajectory—proof that it originated beyond the Sun’s gravitational influence.

The New York Post reports that NASA will release new HiRISE images of the Manhattan-sized object next week, after an extended government shutdown delayed the release.

Astronomers traced the comet’s path toward the constellation Sagittarius, near the Milky Way’s center, signaling that the comet may be older than the solar system itself—possibly 7 to 10 billion years old.

“We are watching something ancient—older than Earth, older than our Sun—passing briefly through our cosmic front yard,” an astronomer noted.

31/ATLAS and Alien Life: Astronomers Debunk Theories as Studies Reveal Galactic Cosmic Ray Effects - USA Herald

Unraveling the Signal: What MeerKAT Found

Earlier attempts to detect OH emissions failed, but an October solar alignment created ideal conditions. MeerKAT finally captured the signal at 2.9 AU from the Sun, confirming active outgassing.

Water loss estimates—about 40 kilograms per second—were previously measured by NASA’s Swift Observatory, reinforcing the natural cometary behavior.

Meanwhile, some scientists—including Harvard’s Avi Loeb—continue to argue that certain anomalies could point to an artificial origin. Many in the scientific community, however, dismiss this, citing natural gas dynamics and measurement limitations.

Continued Mysteries and Future Observations

31/ATLAS displayed an unusual anti-solar tail orientation in early images before later reversing direction. Its composition—rich in CO₂ and dark, icy material—adds further intrigue.

The comet will approach Earth on December 19, 2025, at a safe distance of 167 million miles. NASA’s Juno spacecraft and the ESA’s JUICE mission plan observations in 2026 as the object passes near Jupiter.

Viewers can watch 3I/ATLAS live tonight via the Virtual Telescope Project on YouTube at 11:15 PM ET.