Did you know...

Today, it's nearly impossible to believe the Earth is anything but round. But for most of our history, humans have thought Earth was flat. The one concept our ancient ancestors were missing was gravity. Gravity's effects are the key to determining whether the Earth is actually flat, or not.

If you've taken a flight in coach anytime in the last 20 years, you may have noticed the seat in front of you creeping closer and closer to your knees. The airlines have been squishing seats closer together. It's called the pitch, and it's been chopped down by two to three inches over the years. That's not the only place where the big three are sneaking space from you.

If it wasn't for shoes, we would walk way differently. Think about how you walk when barefoot. The foot lands almost flat. It rolls through the step, and the toes push off. Humans walked this way for millennia. A 2007 study compared how people walk in shoes vs. barefoot. They found there was 12% less of an impact on the knee when the walker was barefoot.

The best part of getting a pizza is opening up the box to unleash the smell of Italian seasoning, melted cheese, and crispy crust. You have Carmela Vitale to thank for that. She's the woman behind those little plastic tables that save your pizza night from utter disaster.

Don't you hate when you pull open a fresh bag of chips and you find SO much empty space? Who are potato chip companies trying to fool? No one! In fact, that space is there for a very good reason: to make sure that your chips arrive to you fresh and delicious. That empty space is filled with a secret ingredient: Nitrogen!

As winter storms roll through, folks who live in icy areas have to re-acquaint themselves with how to navigate a slick icy surface. For some, it comes naturally. For others, that tailbone is going to take a beating. When in doubt, just remember: Walk like the penguins.

What happens if a bird flies into a plane engine? The event is called a bird strike. Each year, bird strikes cost US airlines an estimated $1.2 billion. Only part of those costs are from actual damage. The rest comes from flight delays and cancellations.

Although Venus is easier to reach than Mars, scientists and space agencies around the world show little interest in exploring the planet. Why is it that they have so much enthusiasm in examining Mars but not our neighboring planet, Venus?

Red, yellow, violet - fire hydrants come in many different colors. But it's not for decoration. Certain colors are meant for different types of fires. Each color represents a different GPM or Gallons Per Minute. Higher GPMs are meant for larger fires. Here are the 4 most popular colors and the biggest fires they can extinguish.