Exact date 'planet killer' asteroid to shoot past Earth in closest call for 125 years

The space rock, known as 2011 UL21, is roughly the size of Mount Everest and it is classified as a "planet killer", which means it could destroy continents and cause catastrophic climate change

View 2 Images

A massive world-ending asteroid is set to brush past Earth in the closest call for more than a century.

The rock, which has been named 2011 UL21, is as big as Mount Everest and is scheduled to come within four million miles of Earth on June 27. It will be its closest approach in 110 years and one of the biggest "potentially hazardous asteroids" to pass Earth in 125 years. The asteroid orbits the sun roughly every 1,130 days.

On June 28 and 29, stargazers might be able to catch a glimpse of the hurtling space rock with a decent telescope as that's when it will be at its brightest.

The European Space Agency said in a statement: "This asteroid is larger than 99 per cent of all known near-Earth objects. However, it won’t come anywhere near as close to Earth. At its closest point on 27 June, it will still be more than 17 times as far away as the Moon."

View 2 Images

2011 UL21 - which is estimated to be 7,500 feet across - will make its next close call with earth in 2089 when it will be just 1.7 million miles from our planet. The Catalina Sky Survey project - a batch of telescopes in Arizona - captured the asteroid on October 17, 2011.

"2011 UL21 is quite large and falls into the category of Apollo asteroids," according to the SETI Institute. "Named after the Greek god Apollo, who was known for his epic journeys, these asteroids come in a variety of sizes from a few meters to several kilometres across, like 2011 UL21. More importantly, Apollo asteroids get up close and personal by crossing Earth's orbit, although their orbits around the Sun are larger than Earth's."

Experts have been keeping a close eye on the asteroid for several paths to ensure it isn't veering off course to become a potential risk to the people of Earth.

Astrophysicist and scientific director of the Virtual Telescope Project Gianluca Masi spoke about the need to monitor the asteroid ahead of a live stream of the event.

He explained: "The term 'Potentially Hazardous Asteroid' (PHA) is a precise formal definition, referring to minor planets larger than approximately 460 feet that can come within 4.6 million miles from the Earth.

"In other words, only the largest asteroids capable of approaching close enough to our planet are flagged as PHAs, which does not mean they are going to hit the Earth, but they nonetheless warrant better monitoring."

The asteroid has been labelled a "planet killer", which is a term used to define a space rock which could destroy entire continents. It could also produce enough debris on impact to spark significant changes to the Earth's climate, according to LiveScience. In 2023, MIT scientists explained that a "planet killer" asteroid would not hit the planet for another 1,000 years at least.