The phrase
"ordinary supernova" refers to a type of exploding star that happens quite frequently in the universe. It's called "ordinary" because it's a common event, meaning it occurs relatively often. A supernova occurs when a massive star, much bigger than our sun, runs out of fuel and collapses under its own weight, exploding and releasing a massive amount of energy. These explosions can be incredibly bright and create beautiful remnants in space.
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