1. Water can boil and freeze at the same time
Seriously, it's called the 'triple point', and it occurs when the temperature and pressure are just right for the three phases (gas, liquid, and solid) of a substance to coexist in thermodynamic equilibrium. This video shows cyclohexane in a vacuum.
2. Lasers can get trapped in a waterfall
Oh my gosh, yes. Not only is this an incredible example of total internal reflection, but it also shows how fiber optic cables work to guide the flow of light.
3. We've got spacecraft hurtling towards the edge of our Solar System really, really fast
We all know rockets are fast, and space is big. But sometimes when we're talking about how long it takes for us to get to distant parts of the Solar System (eight months to get to Mars, are you kidding me?) it can feel like our spacecraft are just crawling along out there.
This gif shows just how wrong that idea is by comparing the speed of the New Horizons probe, which flew past Pluto last year, to a 747 and SR-71 Blackbird.
4. An egg looks like a crazy jellyfish underwater
A cracked egg on land might make a big mess, but 18 meters (60 feet) below the surface of the ocean, the pressure on the egg is 2.8 times atmospheric pressure, and it holds it all together like an invisible eggshell. True story.
5. You can prove Pythagoras' theorem with fluid
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6. This is what happens when a black hole swallows a star
As the star gets sucked up into the black hole, a huge jet of plasma is burped out, spanning hundreds of light-years. "When the star is ripped apart by the gravitational forces of the black hole, some part of the star's remains falls into the black hole, while the rest is ejected at high speeds," explains Johns Hopkins University researcher, Suvi Gezari.