Explaining The Universe on Instagram: "@ExplainingTheUniverse teaches you something NEW everyday day 🧠💫 Cracking your knuckles works by rapidly changing the pressure inside the fluid-filled space of a joint. When you pull or bend a finger, the joint capsule stretches, lowering the pressure in the synovial fluid. This causes dissolved gases—mainly carbon dioxide and nitrogen—to form a bubble that collapses or “pops,” creating the cracking sound. • #explore #reels #viral #universe #explaining #s