New city-sized comet is hurtling towards Earth - and will be at closest point within hours

 A new mysterious city-sized comet is hurtling towards earth – just months after "alien" visitor 3i/Atlas whizzed by us. Comet Wierzchoś, also known as C/2024 E1, is rapidly brightening as it approaches its closest point to Earth on Tuesday.

Boffins say the interstellar visitor – first spotted by Polish astronomer Kacper Wierzchoś in March 2024 – has a diameter of around 8.5 miles (13.7 km), arounds two-thirds the length of Manhattan and around four times the island's width.

Some researchers believe it has been slowly falling towards the Sun for as many as three million years and it is expected the gravitational kick from its current solar slingshot will fire it out of our cosmic neighbourhood forever and into interstellar space.

The green comet has since been seen by the James Webb Space Telescope, which detected large amounts of carbon dioxide in its coma, the cloud of gas and dust that surrounds the comet's icy shell.

It will make its closest approach to Earth on Tuesday, February 17, when it will be around 94 million miles (151 million km) from our planet, roughly the same distance away as the sun.

Scientists say it could take several decades or even centuries for it to officially leave the solar system and once it has, it could spend billions of years drifting through the Milky Way, sporadically passing through other alien star systems on its way.

It comes after comet 3i/Atlas made global headlines by speeding past Earth at supersonic speed and grew significantly brighter as it left our solar system.

The previous interstallar visitor, only the third such object to be discovered passing through our solar system, had ignited controversial theories, including that it could be an alien probe on a reconnaissance mission.

Harvard astrophysicist Avi Loeb highlighted its unusual glow, trajectory aligning with planetary orbits and unorthodox path in a list of 17 anomalies he'd noticed while observing the space rock.

The first confirmed interstellar visitor, 1I/'Oumuamua, swept through the Milky Way in 2017 showing no visible coma, the cloud of gas and dust that forms when ice vaporises in sunlight.

The comet accelerated slightly as it departed, prompting speculation that it might be a relic of an alien civilisation.

In 2019, the comet 2I/Borisov developed a coma and a tail. It appeared to have been formed in the outer reaches of another planetary system, giving scientists their first close look at the raw ingredients of worlds beyond our own.

Scientist Paul Hartogh said the world was "probably" entering an era in which interstellar visitors became routine.