By: Olivia Yu

Two enormous asteroids flew by our planet recently, both fortunately with a zero percent chance of impacting Earth. And experts say that there was a chance that we could have caught a glimpse of one of them.

The larger asteroid of the two, (415029) 2011 UL21, “will travel at a distance more than 17 times farther away than the moon on Thursday [June 27] at 4:14 p.m. Eastern time,” according to the New York Times. Despite the space rock’s massive size, it would have been difficult to spot with just the naked eye due to its long distance away from Earth.

Not even a full two days later, the second asteroid, 2024 MK, came far closer to our planet in the early morning, streaking by at 75 percent of the distance to the moon. With sightseeing tools and a clear sky, it could have been seen as a light speck across the sky depending on your location. Stargazers in the American Southwest, atop Hawaii’s Mauna Kea volcano, and people in South America among other places might have spotted the asteroid the easiest and had the best viewing experience.

As stated by the New York Times, the Earth’s atmosphere is “pierced by small asteroids and cometary fragments” from time to time, in addition to “many more rocky and icy shards” that simply miss the planet. The 2024 MK asteroid, the third large object known to pass so close to Earth this century, was less common to do any of this.

Anyone who missed the asteroid’s recent appearance can expect another similar experience in a little less than five years with the giant space rock Apophis. The only difference is that Apophis will fly within an even closer range of the Earth’s surface than 2024 MK and will be visible without any special equipment.