Scientists spot massive ‘anomaly’ five times the size of Hawaii beneath the moon’s largest crater that could be ancient metal from asteroid impact 4 billion years ago
- Huge mass anomaly was spotted beneath the South Pole-Aitken basin on moon
- Researchers say it could be material from iron-nickel core of an ancient asteroid
- Possible metal deposit is heavy enough to weight basin flood down half a mile
Scientists have detected a mysterious mass of material beneath a 1,200-mile crater on the surface of the moon.
The South Pole-Aitken basin on the far side of the moon is said to be the largest crater in the solar system and extends several miles deep.
And, according to the new research, the recently-spotted material is weighing down the basin floor by more than half a mile.
Scientists suspect the unusual deposit beneath the crater may contain metal from the asteroid that formed it.
Scientists have detected a mysterious mass of material beneath a 1,200-mile crater on the surface of the moon (circled). The simulations suggest that the material could be from the iron-nickel core of an asteroid
‘Imagine taking a pile of metal five times larger than the big Island of Hawaii and burying it underground,’ said lead author Peter B. James, from Baylor University’s College of Arts & Sciences.
‘That’s roughly how much unexpected mass we detected.’
In the study, the team analyzed data from NASA’s Gravity Recovery and Interior Laboratory mission (GRAIL).
‘When we combined that with lunar topography data from the Lunar Reconnaissance Orbiter, we discovered that the unexpectedly large amount of mass hundreds of miles underneath the South Pole-Aitken basin,’ James said.
‘One of the explanations of this extra mass is that the metal from the asteroid that formed this crater is still embedded in the moon’s mantle.’
The simulations suggest that the material could be from the iron-nickel core of an asteroid, which, if dispersed into the upper mantle, could be weighing down the basin as seen in the spacecraft data.
It could also be a concentration of dense oxides from the last stage of lunar magma ocean solidification, according to the researcher.
The South Pole-Aitken basin on the far side of the moon is said to be the largest crater in the solar system and extends several miles deep. And, according to the new research, the recently-spotted material is weighing down the basin floor by more than half a mile
‘We did the math and showed that a sufficiently dispersed core of the asteroid that made the impact could remain suspended in the moon’s mantle until the present day, rather than sinking to the moon’s core,’ James said.
The basin itself is thought to have been created about 4 billion years ago, making South Pole-Aitken the largest preserved crater in the solar system.
According to the researcher, it’s ‘one of the best natural laboratories for studying catastrophic impact events, an ancient process that shaped all of the rocky planets and moons we see today.’
WHAT ARE THE THEORIES ON THE ORIGIN OF THE MOON?
Many researchers believe the moon formed after Earth was hit by a planet the size of Mars billions of years ago.
This is called the giant impact hypothesis.
The theory suggests the moon is made up of debris left over following a collision between our planet and a body around 4.5 billion years ago.
The colliding body is sometimes called Theia, after the mythical Greek Titan who was the mother of Selene, the goddess of the moon.
Many researchers believe the moon formed after Earth was hit by a planet the size of Mars billions of years ago. This is called the giant impact hypothesis
But one mystery has persisted, revealed by rocks the Apollo astronauts brought back from the moon: Why are the moon and Earth so similar in their composition?
Several different theories have emerged over the years to explain the similar fingerprints of Earth and the moon.
Perhaps the impact created a huge cloud of debris that mixed thoroughly with the Earth and then later condensed to form the moon.
Or Theia could have, coincidentally, been chemically similar to young Earth.
A third possibility is that the moon formed from Earthen materials, rather than from Theia, although this would have been a very unusual type of impact.