All right, so we all know Earth spins. That’s pretty basic knowledge. What most of us probably don’t know is that Earth wobbles as it spins. This has puzzled scientists for quite some time, but thanks to recent findings, they now think they know why our planet wobbles.

How do they even know Earth wobbles?

You’d think it’d be kind of hard to figure out that Earth is wobbling, anyway. But scientists have known for a while that this is the case. They figured it out thanks to the documentation of stars; as Earth’s axis of spin has shifted, the locations of stars in our sky (from our point of view, anyway) have shifted too.

Unsplash / Modern.affliction

Our planet is just a little off-kilter

In addition to some other causes, it turns out Earth is just a little wobbly by nature (sadly, it’s not just jamming out to the newest hit song from space). Our planet’s axis shifts every year, just by a few centimeters, but enough for scientists to notice. Interestingly, the axis tends to shift towards Hudson Bay in Canada.

Unsplash / Markus Spiske

Age-old shifts

Earth’s wobbly nature isn’t a recent development, either. Scientists have discovered that our planet’s axis of rotation has probably been drifting since the last ice age, 16,000 years ago. This is happening because as glaciers melt, the land underneath them responds by rising up (or collapsing, in some instances), and the redistribution of weight might be causing the axis to shift.

Unsplash / Margo Brodowicz

Man-made tilts

Not all the causes are natural, though. Human creations are also leading to shifts in our planet’s tilt. As we build artificial reservoirs, empty natural water sources, and also contribute to the warming climate, we’re shifting the balance of land and water on Earth, leading to more wobbles on Earth’s axis.

Unsplash / Anthony Da Cruz

Underground secrets

One cause for our planet’s wobbling that might not be as obvious is happening right under our feet—literally. the underground process of convection, where hotter material from Earth’s core rises and the cooler material sinks, is partially to blame for the Earth’s wobbly nature. Scientists have assured us that there aren’t any dangerous consequences for our planet’s wobble, however; it just makes Earth a little extra special.  

Flickr / Doubbt Official