In a celestial double-take, two asteroids recently zipped past Earth, offering scientists a unique chance to study these cosmic travelers up close. These close encounters weren’t threatening, but they provided valuable insights into the nature of asteroids, including those that could potentially pose a risk to our planet.
The first asteroid, aptly named 2011 UL21, made its closest approach on June 27, passing within 4.1 million miles of Earth. At nearly a mile wide, it was classified as a potentially hazardous object, but thankfully, astronomers determined it posed no immediate threat to our planet. This close encounter allowed scientists to utilize NASA’s Deep Space Network radar to bounce radio waves off the asteroid, revealing intriguing details about its structure. The data showed that it wasn’t alone, but rather part of a binary system, with a tiny moonlet orbiting it at a distance of about 2 miles.
Lance Benner, principal scientist at NASA’s Jet Propulsion Laboratory, explained the significance of this discovery: “It is thought that about two-thirds of asteroids of this size are binary systems, and their discovery is particularly important because we can use measurements of their relative positions to estimate their mutual orbits, masses, and densities, which provide key information about how they may have formed.”
Just a couple of days later, on June 29, the second asteroid, 2024 MK, made its appearance. This smaller asteroid, measuring around 500 feet across, came even closer to Earth, passing within 184,000 miles, closer than the moon’s orbit. This close proximity provided researchers with an extraordinary opportunity to study its surface in detail. Employing a similar radio wave bouncing technique, they were able to discern the asteroid’s jagged, complex surface, revealing a rare close-up view of this near-Earth object.
Benner emphasized the unique opportunity this encounter presented, stating, “This was an extraordinary opportunity to investigate the physical properties and obtain detailed images of a near-Earth asteroid.” These recent flybys highlight the ongoing efforts to monitor and understand asteroids, providing crucial insights into their composition, behavior, and potential impact risks, ultimately enhancing our ability to protect Earth from potential threats from space.
