Earth's gravity knocked pyramid-size asteroid off course during recent ultra-close flyby, NASA images reveal

Blurry images of an asteroid stacked next to each other
New "bistatic" images of asteroid 2024 MK show that the space rock has had its solar orbit altered by a recent close approach to Earth. (Image credit: NASA/JPL-Caltech)

Late last month, a gigantic asteroid larger than the Great Pyramid of Giza hurtled between Earth and the moon at more than 21,000 mph (34,000 km/h). The rare, ultra-close encounter allowed astronomers to capture the first-ever pictures of the space rock, which revealed that the near-Earth object was lightly knocked off course by our planet's gravitational pull — forever changing the asteroid's journey around the sun. 

The asteroid, named 2024 MK, is roughly 500 feet (150 meters) across, making it big enough to wipe out a large city. The "potentially hazardous" space rock, which has an irregular and elongated shape, was first spotted barreling toward Earth on June 16 by the NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS) in South Africa.

On June 29, just 13 days after it was discovered, 2024 MK reached its closest point to Earth as it skimmed our planet's orbit at a distance of around 184,000 miles (295,000 kilometers) — or around three-quarters of the distance between Earth and the moon.

Astronomers at NASA's Goldstone Deep Space Communications Complex in California monitored the flyby using the Goldstone Solar System Radar telescope. By bouncing radio waves off the space rock as it shot past Earth, the team created grainy "bistatic" images of the asteroid, which helped them determine its exact shape and map out the concavities and ridges on its surface. The new photos were released July 3 by NASA's Jet Propulsion Laboratory (JPL). 

Just two days before the flyby, on June 27, the same telescope also captured images of the much larger "planet killer" asteroid 2011 UL21 as it passed by our planet at a distance of around 4.1 million miles (6.6 million km). These pictures revealed that this mountain-size space rock has a secret moon hiding in its orbit

Related: No, NASA hasn't warned of an impending asteroid strike in 2038. Here's what really happened.

A diagram of the orbit of asteroid 2024 MK

2024 MK's orbit takes it far away from Earth and into the asteroid belt. (Image credit: NASA/JPL/Small-Body Database Lookup)

The new observations of 2024 MK revealed that the space rock's trajectory has shifted since it was first discovered. This is likely because Earth gravitationally tugged on the asteroid as it passed by us, pulling it slightly closer to our planet.

This alteration was quite significant. The asteroid previously orbited the sun every 3.3 years, spending most of its time in the asteroid belt between Mars and Jupiter. However, scientists now believe that it will take 24 fewer days to complete the route, according to JPL. 

But luckily, "its future motion shows that it [still] does not pose a threat to our planet for the foreseeable future," NASA representatives wrote in a statement.

MK 2024 was originally scheduled to make its next closest approach to Earth in 3037. However, this could now happen several months earlier than expected due to its new orbital trajectory. It is now unclear how close it will get to us or if our planet's gravity will further alter its orbit.

Harry Baker
Senior Staff Writer

Harry is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior, evolution and paleontology. His feature on the upcoming solar maximum was shortlisted in the "top scoop" category at the National Council for the Training of Journalists (NCTJ) Awards for Excellence in 2023.