Newton Blog

« Clinical Vampirism: When You Think You're a Vampire | Blog Home Page | Female Genitalia Are Cool, Too! »

Haunted Hills Where Gravity Is Forsaken

There is a hill just outside of Moorpark, California where gravity seems to be forsaken. Set your car in neutral, and the vehicle will slowly creep up the slope.

Legend has it that in the 1940s, a group of schoolchildren was on a field trip when their bus broke down midway up the hill. Frazzled, and at his wits' end after hours of chaperoning unruly fifth graders, the bus driver ordered the children outside to push. Three-quarters of the way up their strength gave out, along with the bus's brakes. The kids were crushed as the bus rolled down the hill, and the bus driver fled the scene, never to be seen or heard from again. Today it's said that these children still linger at the base of the hill, lending a spectral push to any stopped vehicle.

That story is unique to Moorpark, but the peculiar gravitational anomaly is not.  There are hundreds of documented "gravity hills" across the entire globe, and each is accompanied with its own unusual explanation. The physics-defying characteristics of Spook Hill in Lake Wales, Florida are blamed on an epic, earth-shattering battle between a great warrior chief and a giant gator. In Bedford County, Pennsylvania, a natural magnetic anomaly is often indicted for Gravity Hill's strange powers.

640px-Spookhill.jpgIn all of these locations, cars seem to roll, and water appears to flow, uphill. But rest assured, supernatural forces aren't messing with the laws of physics. These sites are simply natural optical illusions -- just like the art exhibit called "Demon Hill #2," a 3-D optical illusion I wrote about previously.

What you experience at each of these locales has nothing to do with specters or magnets and everything to do with your sense of perception. GPS measurements prove that the slopes are indeed, ever so slightly, slanted downhill, yet the surrounding landscape tricks us into thinking that the descent is really an ascent.

To understand how this trick functions, you should first know that, as humans, we regularly utilize a few ubiquitous markers to gauge spatial orientation: trees, horizon lines, and buildings. Engrained within our brains is the knowledge that the horizon is always horizontal and trees and buildings are always vertical. Thus, where these references are absent or altered, we may misjudge certain physical features. In the case of gravity hills, the straight horizon is obscured by trees and hills, trees are often leaning slightly, and there are no buildings present. This misleading trio of circumstances prompts us to incorrectly assess the angle of the hill.    

Just like when you're looking at a painting, false perspective may also play a role. If trees gradually become larger or smaller in the distance, you'll think something is similarly larger or smaller than it really is.

As with most optical illusions, knowing that what you're seeing is a farce has no effect whatsoever on how you perceive it. You can tell yourself that the water is really flowing downhill, but that won't change your perception that the water is flowing uphill. This constitutes a lack of cognitive control that's just as spooky as the illusion, itself.

(Image: Spook Hill by Marc Averette via Wikimedia Commons)