3I/ATLAS
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Our solar system has an unexpected visitor, and it has just put its foot on the accelerator. An interstellar object, dubbed 3I/ATLAS, is currently hurtling through our celestial neighbourhood on what NASA has described as an 'alarming speed run'.

This rare comet, which journeyed from an entirely different star system, is providing scientists with a unique, fleeting opportunity to study a true alien artefact.

A 'Ghost' from Another Star: What Is 3I/ATLAS?

3I/ATLAS is only the third known object from outside our solar system 'to be discovered passing through our celestial neighbourhood', according to NASA. It is a true interstellar ghost, born in an unknown star system likely billions of years ago.

It was violently ejected from its home and sent drifting through the cold, dark void of interstellar space. For aeons, it travelled alone between the stars until it was captured by our sun's gravity, pulling it in for a brief, high-speed fly-by.

From 137,000 to 152,000 MPH: Why Is the Comet Speeding Up?

The comet's alarming acceleration is a direct result of its rendezvous with our sun. When 3I/ATLAS was first spotted, it was travelling at an already staggering 137,000 miles per hour.

After reaching its perihelion—its closest point to the sun—on 29 October, it has been slingshotted by the star's immense gravity. It is now moving away from the sun and closer to Earth, having picked up speed to approximately 152,000 mph.

This gravitational boost has effectively 'supercharged' its exit, flinging it back towards deep space faster than it arrived.

All Eyes on the Visitor: How NASA Is Tracking 3I/ATLAS

NASA is coordinating multiple missions to study the rare visitor before it vanishes forever. The agency's telescopes are locked onto the object, analysing its composition and behaviour.

By studying the light and vapours emanating from 3I/ATLAS, scientists hope to learn what it is made of. This data could offer unprecedented clues about the chemical makeup of its home star system, offering a physical sample from a distant part of the galaxy. The Hubble Space Telescope, in particular, has been crucial in this effort.

A Skyscraper or a Mountain: The Mystery of the Comet's True Size

While its speed is known, the comet's precise size remains a significant mystery. Based on observations from Hubble in August, astronomers have only been able to establish a wide range for its nucleus.

They are confident its diameter is no smaller than 440 metres, roughly the height of a large skyscraper. However, it could be as large as 5.6 kilometres wide, making it a veritable mountain hurtling through space.

This uncertainty makes it difficult to predict its brightness or how it will behave as it continues its journey. This is a developing story, and space agencies continue to provide updates as they track its path.

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