3I/ATLAS Nears Earth With Eerie 'Heartbeat' as Spectator Predictions Explode Online

A strange pulse coming from 3I/ATLAS has gotten the public talking, as new telescope data shows the object brightening and dimming in a clean 16.16-hour rhythm.

Astronomers describe the pattern as a steady heartbeat that boosts the object's glow by 20 to 40 per cent with striking precision. Astronomers say that the regular pulses are caused by surface ice pockets heating up during each rotation.

As these patches face the Sun, gas jets erupt at roughly 985 miles per hour, shooting material up to an estimated 15,900 miles from the surface.

Each rotation exposes the same regions, producing the repeated heartbeat first identified in a scientific study released in August 2025.

Speaking to the New York Post, Harvard Professor Avi Loeb says that the coma should have soft light variations. The coma surrounds the dark core with a vast cloud of gas and dust that typically reaches hundreds of thousands of miles.

He adds that typical comets with a similar structure show around 5% brightening. Loeb also pointed out other irregularities, including odd tail directions, unusual colour changes, and subtle path shifts. NASA has rejected these claims and says that the behaviour is caused by foreign chemistry from a distant solar system.

The Predictions: What Astronomers Expect in the Coming Days

On X, an Astronomy/Cosmology-focused account, Viu Mobile shared its speculations on what we can expect to see in the coming days following the recent 3I/ATLAS update.

Tail Behaviour Remains Steady

Prediction models show that the pencil-thin main tail will keep its stiff shape. It is expected to remain still with the object's direction of travel instead of pointing straight away from the Sun. It's described as a signature of a stable jet firing in the same fixed direction each day.

Jet Orientation Expected To Stay Locked

The orientation of the jet is expected to move only two to three degrees in the sky plane through the first half of December. This stable movement suggests that no new vents or dust eruptions are forming on the surface.

Brightness Trend Points To Gradual Fading

Viu Mobile also predicts a smooth fade of around 0.3-0.5 magnitudes. Studies involving repeated brightness sampling show no sign of large swing cycles beyond the heartbeat pattern. Low-frequency modulation is expected to remain minimal.

Dust Fan To Broaden

A faint sheet-like dust fan sits slightly offset behind the main tail. This feature is expected to widen by as much as sixty per cent, based on the slow spreading of heavier dust grains released earlier in the journey.

Fragmentation Risk Considered Low

There is no evidence of cracks, sudden outbursts, or rapid dispersal. Imaging from late November through early December shows no signs of breakup or rotational instability.

Close Approach and Ongoing Monitoring

The 3I/ATLAS comet is expected to pass Earth at a distance of about 170 million miles on 19 December. NASA and the UN have reiterated that it poses no danger to us.

Despite this, planetary defence teams organised a formal surveillance on 27 November with help from the Asteroid Warning Network.

Astronomers and experts worldwide are closely monitoring the object, concerned that it may not be as harmless as others claim. However, others are excited to hear more about any 3I/ATLAS news as it draws closer to Earth.