‘Potentially hazardous’ asteroid the size of a skyscraper will skim past Earth next week, NASA warns

A ‘potentially hazardous’ asteroid the size of a skyscraper is set to zip past our planet next week, according to NASA.

The asteroid, called 2024 ON, is expected to come within 620,000 miles from the Earth’s surface at 10:19 UTC (11:01 BST) on Tuesday, September 17.  

2024 ON has a diameter anywhere between 721 and 1,575 feet (220 to 480 metres) – meaning it could be nearly as big as the One World Trade Center in New York.

As it flies past Earth, it will be travelling at a speed of 8.8km per second or 19,685 miles per hour – roughly 25 times the speed of sound. 

The asteroid is ‘potentially hazardous’, although thankfully it’s not expected to pose a danger to our planet and its inhabitants. 

An asteroid is defined as ‘potentially hazardous’ if it comes within 0.05 astronomical units (4.65million miles) of Earth and is larger than 459 feet (140 meters) in diameter. 

Despite being more than two times further out than the moon when it makes its close approach, the asteroid is classed as a near-Earth object (NEO) and is being tracked by the space agency. 

‘NEOs are comets and asteroids that have been nudged by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth’s neighbourhood,’ said NASA.

‘Composed mostly of water ice with embedded dust particles, comets originally formed in the cold outer planetary system while most of the rocky asteroids formed in the warmer inner solar system between the orbits of Mars and Jupiter. 

‘The scientific interest in comets and asteroids is due largely to their status as the relatively unchanged remnant debris from the solar system formation process some 4.6 billion years ago.’ 

The asteroid, called 2024 ON, is expected to come within 620,000 miles from the Earth’s surface at 10:19 UTC (11:01 BST) on Tuesday (artist’s impression)

NASA lists 2024 ON as one of the upcoming close approaches on its online tracker, which compiles upcoming objects that are getting closer and closer to Earth. 

Unfortunately, this asteroid will be too small to be seen by the naked eye, or even with an average telescope. 

Measuring 1,575 feet in diameter at the very most, 2024 ON is actually puny compared to the largest known asteroid, Ceres, which is 580 miles in diameter (more than 3 million feet). 

Asteroids – large rocky chunks left over from collisions during the ancient solar system – travel at high speeds due to the immense gravitational pull on them. 

As they revolve around the sun in ‘elliptical’ (elongated) orbits, the asteroids also rotate erratically, tumbling as they go.