Scientists have discovered a mysterious lump on the moon's far side, and it's 5 times bigger than Hawaii's Big Island
- Earth's moon may be hiding a giant metallic lump beneath an impact crater called the South Pole-Aitken Basin.
- The feature may be the core of an asteroid or planetary chunk, or possibly a frozen ocean of magma.
- The mysterious object is about five times the size of the Big Island of Hawaii. It's buried more than 185 miles deep.
- The crater can't be seen because it's on the far side of the moon, though China's latest lunar rover is now exploring the area.
- Visit Business Insider's homepage for more stories.
The far side of the moon is hiding a colossal secret beneath its airless, pockmarked surface.No one is quite sure what it is - the most precise wording researchers can muster is a "large excess of mass."
"Imagine taking a pile of metal five times larger than the Big Island of Hawaii and burying it underground," Peter B. James, a geoscientist at Baylor University, said in a press release. "That's roughly how much unexpected mass we detected."James is one of a handful of US scientists who announced their discovery in a study published in the journal Geophysical Research Letters.
The gravitational force of "whatever it is, wherever it came from," James said, is so great that it drags down the floor of the basin by more than half a mile.
A giant secret below the solar system's oldest, biggest preserved crater
China Aerospace Science and Technology Corporation (CASC)
Whatever formed the basin nearly 4 billion years ago remains a mystery, but the blow was so strong that it likely punched all the way through the moon's crust and tossed part of the lunar mantle - a deeper geologic layer - onto the surface.
For these reasons, geologists are eager to explore the basin to glean clues about the moon's formation and composition. In fact, China recently landed its Chang'e 4 mission there (specifically within a roughly 111-mile-wide crater called Von Kármán) to study part of the basin.James and his colleagues discovered the anomaly beneath the basin by merging data from two NASA missions at the moon. One is the Lunar Reconnaissance Orbiter, which continues to constantly photograph the lunar surface and has led to high-definition surface elevation maps.
The other mission was the Gravity Recovery and Interior Laboratory (GRAIL), which involved two spacecraft - GRAIL A and GRAIL B - working in tandem to detect variations in the strength of the moon's gravitational field. Larger variations helped tease out information about the moon's core, and subtler ones revealed unseen mineral deposits, asteroid impact sites, and subsurface features."When we combined that with lunar topography data from the Lunar Reconnaissance Orbiter, we discovered 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."
Another explanation is that, following the impact that formed the basin, a huge ocean of metal-rich magma pooled inside of the lunar crust and solidified into a dense slab.
- MPs should put pressure on Centre to include Kerala's demands in central budget:CM
- Final stage of Budget 2021-22 commences with Halwa ceremony
- Farmers' Protest: Local eateries facing tough time due to free langars at Singhu Border
- Venture Capital funding in India hits $3.1 billion in Q4 of 2020, says KPMG report
- A scary proposal to use facial recognition and AI by an Indian state has experts fuming