> [10 Things: What We Learn About Earth by Studying the Moon](https://solarsystem.nasa.gov/news/812/10-things-what-we-learn-about-earth-by-studying-the-moon/?utm_source=TWITTER&utm_medium=NASA&utm_campaign=NASASocial&linkId=64050866)

> By Isabelle Yan, NASA’s Goddard Space Flight Center

> *"Earth’s magnetic field is our shield, constantly protecting us from harmful solar wind or cosmic ray particles. This important buffer is generated by the fast-flowing movement of liquid iron and nickel in Earth’s outer core.*

> *One thing that makes this molten ocean of metal move is the Moon’s gravity. Recent research suggests that the Moon’s gravity tugs on Earth’s mantle layer (which sits on top of the outer core). This causes the liquid, outer core to slosh around, helping to generate the energy needed to maintain our magnetic field."*

The moon's gravity also tugs on the non-spherical Earth's axis as well, leading to a [perfectly synchronized Chandler Wobble](https://geoenergymath.com/2019/02/09/71/).
![](https://geoenergymath.files.wordpress.com/2019/02/cw_time_series_1950_1962.png)

and of course the [lunisolar tug largely controls the modulation in the Earth's length-of-day (LOD)](https://geoenergymath.com/2019/02/13/length-of-day/)
![](https://geoenergymath.files.wordpress.com/2019/02/baa0cq.png)

> *"Earth’s signature 23.5-degree tilt on its axis is due to the Moon keeping it in check. The 23.5-degree angle ensures our planet is safe to live on, as a more exaggerated tilt would cause more extreme seasons.*

> *Without the Moon’s gravity, Earth would wobble more violently on its axis, drastically altering the climate. Besides maintaining climate stability, the Moon also sets the rhythm of Earth — the highs and lows of our tides — which affects the variety of ways we use the ocean for food, travel and recreation. Precisely measuring the mass, size and orbital properties of the Moon is essential for predicting these rhythms of tides and seasons. "*

The Moon's gravity likely has an equally significant effect on both tides and on the dynamic rhythm of ENSO. [This equivalence is too similar to ignore](https://geoenergymath.com/2019/02/25/long-period-tides/).

![](https://geoenergymath.files.wordpress.com/2019/02/rkzhjm.png)

That NASA post on the Moon's influence on the Earth's behavior is timely as it intersects nicely with three blog posts I have written in the past month.