‘Odd-shaped’ asteroid with ‘strikingly complicated’ structure leaves NASA scientists surprised

A larger-than-expected asteroid with an unusual shape orbiting the sun has left scientists in shock.

NASA's Lucy spacecraft, which launched back in 2021, is busy exploring the asteroid belt between Mars and Jupiter.

The mission is set to explore a 'record-breaking' number of asteroids, with its main target, the Jupiter Trojan asteroid Eurybates, to be investigated in August 2027.

Lucy has undertaken a couple of 'practice runs', however, and it's most recent was a fly-by of the mysterious Donaldjohnson asteroid.

During its second-ever fly-by on April 20, Lucy got 600 miles (960 km) away from Donaldjohnson.

It beamed back a collection of photos of the 'structurally complex' rock which had scientists stunned.

Firstly, that's because the asteroid, thought to have formed some 150 million years ago, was larger than first thought, measuring up at around 5 miles (8 km) long and 2 miles (3.5 km) wide at its widest point.

That's roughly the size of two of New York's Central Parks placed end-to-end.

The full asteroid was too large to fit in Lucy's image finder, hence why a full-sized photo isn't available.

Secondly, the white asteroid is an 'odd shape,' featuring a 'narrow neck' connecting two lobes which, as NASA put it, 'looks like two nested ice cream cones.'

The photos showed this 'elongated contact binary'—meaning it's an object formed when two smaller bodies collide.

Not only are the photos extraordinary, but they could help inform us more on the inner-workings of space.

NASA's Lucy spacecraft will explore a 'record-breaking' number of asteroids (Naeblys/Getty Images)

Hal Levison, principal investigator for Lucy at Southwest Research Institute in Boulder, Colorado, said: “Asteroid Donaldjohanson has strikingly complicated geology.

“As we study the complex structures in detail, they will reveal important information about the building blocks and collisional processes that formed the planets in our Solar System.”

More photos are still to be downloaded and analyzed by Lucy, which could tell us even more.

The spacecraft is also equipped with other scientific instruments, including the L’Ralph color imager and infrared spectrometer and the L’TES thermal infrared spectrometer.

NASA confirmed this data will be retrieved and analyzed over the coming weeks.

The Donaldjohnson asteroid is so large, Lucy's camera can't capture it in its entirety (NASA)

Tom Statler, program scientist for the Lucy mission at NASA Headquarters in Washington, said: “These early images of Donaldjohanson are again showing the tremendous capabilities of the Lucy spacecraft as an engine of discovery.

"The potential to really open a new window into the history of our solar system when Lucy gets to the Trojan asteroids is immense.”

Lucy's first fly-by took place on November 1, 2023, a little more than two years after the spacecraft was launched.

Considered a 'test run' for the system, Lucy beamed back data on Dinkinesh, which was also found to be a 'surprisingly complex' rock like Donaldjohnson.

It featured a trough where around a quarter of the asteroid had suddenly shifted, as well as a ridge, and a 'separate contact binary satellite' later dubbed Salem.

While Lucy still has a couple of years until it reaches Jupiter Trojan asteroid Eurybates, it may still teach us a plenty about how our universe was formed in the meantime.