---
title: "Astronomers Discover “Deep Structure” Under Moon’s Largest Crater"
description: "A team of astronomers found a \"large excess of mass\" under the largest crater of the Moon, called the Aitken basin near the South Pole."
date: "2019-06-10"
modified: "2019-06-10"
authors:
  - name: "Victor Tangermann"
    job_title: "Senior Editor"
    link: "https://futurism.com/authors/victor"
url: "https://futurism.com/the-byte/deep-structure-mass-moon-crater"
categories:
  - "Astronomy"
  - "Moon"
  - "Space"
tags:
  - "asteroid"
  - "crater"
  - "moon"
  - "the digest"
---

# Astronomers Discover “Deep Structure” Under Moon’s Largest Crater

![A team of astronomers found a "large excess of mass" under the Moon's largest crater called the Aitken basin near the South Pole.](<https://futurism.com/wp-content/uploads/2019/06/deep-structure-mass-moon-crater.png>)
*\<em\>Image: NASA\</em\>*

## Mass Anomaly

A team of astronomers found a "large excess of mass" under the Moon's largest crater, the Aitken basin — likely a relic from an ancient asteroid impact event, but perhaps something much stranger.

"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 in Waco, Texas [in a statement](<https://phys.org/news/2019-06-mass-anomaly-moon-largest-crater.html>). "That's roughly how much unexpected mass we detected."

## Asteroid Shrapnel

The strange mass extends to "depths of more than 300 km \[186 miles\]" according to the researchers' paper, which [was published](<https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL082252>) in the journal *Geophysical Research Letters* earlier this year.

To find the mass, the researchers looked at changes in the strength of gravity around the Moon by analyzing data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission.

## Moon Magma

Computer simulations suggest that the crater could have been created by an iron-nickel core asteroid that spread out into the upper mantle of the Moon during impact while the metal "could remain suspended in the Moon's mantle until the present day, rather than sinking to the Moon's core," James said.

Another theory floating around as to what the mass might be the result of: lunar magma ocean solidification, or the process in which a once molten Moon surface solidified over billions of years while forming dense oxides.

**READ MORE:** [Mass anomaly detected under the moon's largest crater](<https://phys.org/news/2019-06-mass-anomaly-moon-largest-crater.html>) \[Baylor University\]

**More on the Moon:** *[Weird Flashes Keep Appearing on the Moon and Scientists Don't Know Why](<https://futurism.com/the-byte/flashes-moon-scientists>)*

## Author
I've been at Futurism since 2017, where my role has evolved to encompass design, writing, and increasingly editing. I've always been fascinated by space exploration and advanced transportation, which I've leaned into by interviewing luminaries in those fields while closely following the dimensions of policy and regulation that allow next-generation projects to succeed -- or, sometimes, to fail. I'm also keenly interested in the effects of generative AI on society, policies, and democratic institutions, as well as clean energy, physics and biology, and the vagaries of tech leadership. My work for Futurism has been cited by publications including Ars Technica, Gizmodo, PC Magazine, Jalopnik, Fox News, and the New York Post. I spent my childhood living in locations including Manila, the Philippines, and Geneva, Switzerland, attended McGill University, and now live in Toronto, Canada. Before Futurism I worked at AskMen and a small photography studio. In my free time, I'm an avid gardener, foodie, and craft beer lover, as well as a maker of artisanal hot pepper sauces. I have a magnificent dog named Freida.

### Author social links  
[Bluesky](<https://bsky.app/profile/vtanger.bsky.social>)