Explosions: From Stars, To Shrimp?

When talking about explosions, most people talk about man-made devices such as grenades, remote explosives, or even nuclear warheads. These creations are what we tend to base our perspectives on when it comes to violent releases of energy. But the scale of explosions goes much further than human-made devices, ranging from massive celestial bodies to astounding organisms only a few inches in length.

Let’s start with the definition of an explosion. In its simplest terms, an explosion is a large expulsion of energy expanding outward from a specific source, radiating heat, light, and a shockwave. This is the most widely accepted definition, however criteria can vary (Keller et al 2014). We see these in our everyday lives, albeit at a much smaller degree, such as with a gas stove, an engine within a car, or something more obvious like fireworks.

Figure 1: a standard combustion engine that uses “micro-explosions” for rotation in the wheels. These micro-explosions are caused by a system where pistons within containers called cylinders have gas pumped into them. This gas is then compressed by the pistons and ignited by a spark plug. This ignition causes a small shockwave, pushing down on the piston and in turn rotating a crankshaft, causing the wheels to spin based on other mechanisms that sadly don’t involve explosions (Colwell, 2019)

If we scale it up to the largest explosions, we get stars, some of the most fascinating objects in the universe. Imagine a power plant spanning millions of kilometres across with a fusion reactor at its core. Once a mass of hydrogen reaches a certain threshold of mass and heat, the pressure at its core will cause the atoms to fuse into helium. This process releases massive amounts of energy (NASA 2019). For example, the sun produces 4.0 x 10^26 each second by fusing around 700 million tons of material, confirmed by using Einstein’s equation of mass/energy equivalence (E=mc^2). To put this into scale, that’s close to 20 billion times the most powerful nuclear bomb ever tested on Earth (Seigel 2022). However, this is far from the largest explosion a star can have in its lifetime.

At the end of a stars life, it runs out of hydrogen to fuse in its core. Normally, this is where stars like the sun tend to die out, but it’s different for larger stars. For them, the pressure and temperature in their cores is so high they begin to fuse heavier and heavier elements, such as oxygen, neon, magnesium, and silicon (NASA 2026). The final stage within a a larger stars life comes when silicon fuses into iron. As the end all be all of stars, Iron has one of the most stable nuclei in the universe. An attempt to fuse heavier elements from it would only consume energy instead of releasing it. Because of the lack of radiation, the outer layers will collapse onto the core due to its immense gravity. Figure 2 shows the aftermath of this event and the expelled materials in the cloud around it. This process has enough energy and heat to fuse electrons and protons into neutrons, creating up to 10^44 J of energy. This process will either create a neutron star, a star basically made of neutron soup, or, with a star with more than 15 times the mass of the sun, a black hole (Nave 2000).

Figure 2: The remnants of a supernova first seen in 1537 from a star approximately 13,000 light years away. As seen in the image, the different coloured stardust is made up of all of the fused elements prior to its explosion. This is one of the main ways different elements are formed and dispersed throughout a star system (NASA 2026).

Although these violent cosmic events are some of the most impressive explosions out there, we can find even more interesting ones down here on Earth. Scaling it down, we find that the smallest explosions in nature are caused by the hands of a crustacean that spans only 4-10 inches in length. The mantis shrimp (Order: Stomatopoda) and their varying species have extremely interesting features, but none of which outclass its world class punching and spearing power. As most arthropods, the mantis shrimp has something called raptorial appendages, but instead of pincers or claws, they’re fitted with something called a dactyl club, a club like striking appendage that is entirely unique to the mantis shrimp. Figure 3 shows the actual mechanism and the process behind the actual punch. The club acts similarly to a spring loaded hammer, where the shrimp has the ability to latch its clubs into place, storing massive amounts of energy before releasing it as kinetic energy (Spence 2025).

Figure 3: a diagram of the punching mechanism of a mantis shrimp and its similarities with a human hand. The latch within a mantis shrimp’s club is used to store large amounts of potential energy before distribution, similar to if a human drew back a bow. When the mantis shrimp releases a punch, the stress is distributed not just by the muscles and tendons themselves, but by something called a saddle, which distributes the force across the appendage(Lynch 2021).

When a mantis shrimp releases one of its punches, it comes in two stages. The punch itself occurs when the latch releases the club, causing it to accelerate to 22 m/s within 3 milliseconds. This speed, comparable to a .22 caliber bullet, hits the target with around 1500 newtons of force, which is used to crack or break open shells of crabs or snails. The second stage is caused by something called a cavitation bubble, a region of space is basically a vacuum caused by the speed of the punch itself. This superheats the water around it to temperatures similar to the surface of the sun. This destructive force can be seen in Figure 4 seen with the collapsing cavitation bubble. Once the cavitation collapses, it sends out an extremely powerful shockwave that, when combined with the damaged exterior of the target, normally stuns or kills it(National Geographic 2019).

Figure 4: An image of the cavitation caused by the a peacock mantis shrimp’s punch. As seen, there is a flash of red light within the bubble, and heat radiating outward from the impact cite. This also creates a cavitation bubble, which collapses and sends out a shockwave that causes lethal damage to many of the species that the shrimp preys upon.

Although explosions themselves are violent and catastrophic to those around them, they can also be used for the to make leaps in scientific research. Whether it be about gaining insight on what happened early in the universe from stars that formed in the in its early stages. Or witnessing and recording astounding works of nature on this very planet, like a shrimp with the power of the sun in the palm of its hand. The very explosions that shake the world on the daily could very well lead to scientific breakthroughs like no other.

References

Colwell, KC. 2019. “Here’s How Your Car’s Engine Works.” Car and Driver. https://www.caranddriver.com/features/a26962316/how-a-car-works/.

Keller, J., M. Gresho, A. Harris, and A. Tchouvelev. 2014. “What is an explosion?” ScienceDirect.com. https://www.sciencedirect.com/science/article/pii/S0360319914012890.

NASA. 2019. “Chapter 1 – A Star is Born.” NASA Science. https://science.nasa.gov/exoplanets/resources/life-and-death/chapter-1/.

NASA. 2026. “Stars.” NASA Science. https://science.nasa.gov/universe/stars/.

Sartore, Joel, NAT GEO, and GREG LECOEUR. 2019. “Mantis shrimp, facts and information.” National Geographic. https://www.nationalgeographic.com/animals/invertebrates/facts/mantis-shrimp.

Siegel, Ethan. 2022. “Ask Ethan: How Can A Nuclear Bomb Be Hotter Than The Center Of Our Sun?” Forbes. https://www.forbes.com/sites/startswithabang/2020/03/28/ask-ethan-how-can-a-nuclear-bomb-be-hotter-than-the-center-of-our-sun/.

Spence, Katie. 2024. “Mantis shrimp: The crustacean that packs a punch.” Natural History Museum. https://www.nhm.ac.uk/discover/mantis-shrimps.html.