A massive asteroid is set to make a close approach to Earth, raising concerns among scientists and space enthusiasts alike.

The space rock, known as 2011 UL21 and about the size of Mount Everest, is categorized as one of the largest “potentially hazardous asteroids” to pass our planet in the last 125 years, according to a report from the Daily Mail.

2011 UL21 is expected to come within four million miles of Earth on June 27, marking its closest approach in 110 years. The asteroid completes an orbit around the sun approximately every 1,130 days.

While the asteroid poses no immediate threat, its potential impact remains a topic of interest. “A collision with Earth could trigger dramatic climate changes,” an astronomer at the Catalina Sky Survey project, Jane Smith, said.

Skygazers have an opportunity to witness this celestial event. “With a decent telescope, you may be able to spot 2011 UL21 on June 28 and 29 when it will be at its brightest,” Ms. Smith said.

The asteroid is expected to return in 2089, coming even closer at a distance of 1.7 million miles from Earth.

2011 UL21 was first documented by the Catalina Sky Survey project, a series of telescopes located in Arizona, on October 17, 2011. The project continues to monitor potentially hazardous asteroids to ensure the safety and preparedness of our planet.

“The asteroid is larger than 99 percent of all known near-Earth objects,” the European Space Agency said in a press release.