Explaining shocks in novae: As the explosion begins, it ejects a cooler, slower wave of gaseous material, relatively speaking. Behind it, though, is a hot, fast wave speeding right behind it. The collision of the two ejections produces a shockwave, which results in a spectacular explosion of heat and light. “The bigger the shock, the brighter the nova,” Chomiuk said. “We believe it’s the speed of the second wave that influences the explosion.”
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