Halley's Comet is one of the most famous celestial objects, and even those who have no interest in astronomy have most likely heard of it. The space rock marked the first time astronomers ...
Because Halley's Comet only comes around once every 75 years, space agencies around the world took advantage of this once-in-a-lifetime opportunity. Before Vega 1 went to the comet, it first flew ...
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