Watching things explode? Always fun. Watching things explode in super slow motion? Even better. As loyal viewers of The Slow Mo Guys YouTube channel we already knew those things to be true, though. What we didn’t know is how much fun it is to watch things explode in super slow motion under water.

In their latest video, Dan and Gavin set some M1000 “bangers” (that’s the British slang for these particular kinds of fireworks) off in a fish tank and filmed it with their super slow-mo camera. The total explosion time is so fast (0.01004 seconds) it’s really hard to see much of anything with the naked eye; it just registers as a quick little “flunfth.”

However, when watched back in slow-mo it suddenly looks like a star exploding, as a ball of light quickly expands from the energy of the blast, before being sucked back as though through a black hole, though it produces another bright flash as it implodes in a puff of smoke. And when watched at a crazy slow 120,000 frames per second, it looks less like an exploding star and more like a planet in a sci-fi film that has had its core activated by a nuclear bomb.

So why does it happen like this, with the explosion followed by an implosion? The guys weren’t exactly sure, but it looks as though once the energy of the blast is exhausted (that little pause you can see between the expansion and contraction), the pressure from the water trying to fill the empty space created by the blast crushes back on the gasses. That could be causing the second flash, as the gas is compressed back together.

While we didn’t realize how much fun, and enlightening, under water explosions could be, we’re now going to need a lot more of them now. What should The Slow Mo Guys film blowing up in the fish tank next? Tell us your best ideas in the comments below.

Images: The Slow Mo Guys