---
title: "MIT: A “Dynamo” Inside the Moon Shut Down a Billion Years Ago"
description: "A team of MIT scientists belive that the magnetic field of the Moon was caused by a crystallizing iron core \"dynamo\" about a billion years ago."
date: "2020-01-03"
modified: "2020-01-03"
authors:
  - name: "Victor Tangermann"
    job_title: "Senior Editor"
    link: "https://futurism.com/authors/victor"
url: "https://futurism.com/the-byte/mit-dynamo-moon-shut-down-billion-years-ago"
categories:
  - "Astronomy"
  - "Moon"
  - "Science & Energy"
  - "Space"
tags:
  - "magnetic field"
  - "moon"
  - "the digest"
---

# MIT: A “Dynamo” Inside the Moon Shut Down a Billion Years Ago

![A team of MIT scientists belive that the magnetic field of the Moon was caused by a crystallizing iron core "dynamo" about a billion years ago.](<https://futurism.com/wp-content/uploads/2020/01/ancient-dynamo-moon-shut-down-billion-years.jpg>)
*\<em\>Image: NASA\</em\>*

## Moon Energy

Billions of years ago, scientists believe that the Moon had a magnetic field, much like Earth's.

But that field shut down at some point — and a team of MIT scientists now say it was because of a crystallizing iron core that shut down an ancient "dynamo" inside the natural satellite about a billion years ago.

## One Billion Years

"The magnetic field is this nebulous thing that pervades space, like an invisible force field," Benjamin Weiss, professor of planetary sciences at MIT, said in a statement. "We’ve shown that the dynamo that produced the moon’s magnetic field died somewhere between 1.5 and 1 billion years ago, and seems to have been powered in an Earth-like way."

Scientists believe that the churning of the Moon's core as it crystallized created a powerful dynamo effect. The team's new timeline falls in line with conventional theories that the Moon's magnetic field stopped after its core fully crystallized.

## Ancient Magnetic Rocks

The team examined the magnetic signals in lunar rocks collected during NASA's Apollo missions.

They found that rocks as old as 4 billion years showed signs of a strong magnetic field — about twice as strong as Earth's current one.

**READ MORE:** [Scientists pin down timing of lunar dynamo’s demise](<http://news.mit.edu/2019/when-lunar-dynamo-ended-0101>) \[MIT News\]

**More on the Moon's magnetic field:** *[Spiral Formations on the Moon Appear to Deflect Cosmic Rays](<https://futurism.com/the-byte/moon-formations-lunar-swirls>)*

## 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>)