The Science Siblings are celebrating Heart Month with some facts and a DIY model. “For example, the size of your heart is about the same size as your fist. And also, the average heart weighs ...

For their latest project, To Scale: Time, Overstreet and Gorosh decided to build a scale model of time. All 13.8 billion years of it. The 140 million miles between Earth and Mars became 302 feet.