What Causes Those Horrifying, Car-Swallowing Sinkholes?

 Logan Mock-Bunting/Getty Images
Logan Mock-Bunting/Getty Images

On Thursday morning, a St. Louis couple left a YMCA gym and discovered that their car was conspicuously missing from its spot. Upon further investigation, they realized it was actually still parked there—only it was 20 feet underground, swallowed up by a sinkhole

However terrifying they may be, sinkholes aren't that unusual in Missouri; the state is home to at least 15,000 of them, and it's had sinkhole-related regulations since 1853. That's nothing in comparison to Florida, though, which has the most sinkholes in the U.S. There's even a company that bills itself as the Sunshine State's "most experienced residential sinkhole repair company."

So what causes sinkholes to form, anyway? YouTube’s Practical Engineering, led by civil engineer Grady Hillhouse, set out to put this question to bed by creating a miniature replica of a sinkhole.

The common denominator in both instances of natural and human-created sinkholes? Water. Not unlike the natural process that causes caves to form, many of the human-made sinkholes in recent memory have been the result of pipes leaking and causing internal erosion of the soil. This process leaves all but the roadway acting as a "final bridge" above the deep, dark void. You can probably guess what happens next. Watch the full video below:

Friday’s Best Amazon Deals Include Digital Projectors, Ugly Christmas Sweaters, and Speakers

Amazon
Amazon
As a recurring feature, our team combs the web and shares some amazing Amazon deals we’ve turned up. Here’s what caught our eye today, December 4. Mental Floss has affiliate relationships with certain retailers, including Amazon, and may receive a small percentage of any sale. But we only get commission on items you buy and don’t return, so we’re only happy if you’re happy. Good luck deal hunting!

3D Map Shows the Milky Way Galaxy in Unprecedented Detail

ESA
ESA

It's our galactic home, but the Milky Way contains many mysteries scientists are working to unravel. Now, as The Guardian reports, astronomers at the European Space Agency have built a 3D map that provides the most detailed look at our galaxy yet.

The data displayed in the graphic below has been seven years in the making. In 2013, the ESA launched its Gaia observatory from Kourou in French Guiana. Since then, two high-powered telescopes aboard the spacecraft have been sweeping the skies, recording the locations, movements, and changes in brightness of more than a billion stars in the Milky Way and beyond.

Using Gaia's findings, astronomers put together a 3D map that allows scientists to study the galaxy in greater depth than ever before. The data has made it possible to measure the acceleration of the solar system. By comparing the solar system's movement to that of more remote celestial objects, researchers have determined that the solar system is slowly falling toward the center of the galaxy at an acceleration of 7 millimeters per second per year, The Guardian reports. Additionally, the map reveals how matter is distributed throughout the Milky Way. With this information, scientists should be able to get an estimate of the galaxy's mass.

Gaia's observations may also hold clues to the Milky Way's past and future. The data holds remnants of the 10-billion-year-old disc that made up the edge of the star system. By comparing it to the shape of the Milky Way today, astronomers have determined that the disc will continue to expand as new stars are created.

The Gaia observatory was launched with the mission of gathering an updated star census. The previous census was conducted in 1957, and Gaia's new data reaches four times farther and accounts for 100 times more stars.

[h/t The Guardian]