While there's a sure-to-be-stunning Perseid meteor shower coming up later in the week, another spectacle is trying to steal the show tonight. Remnants of the comet PanSTARRS C/2017 S3 are going to pass by Earth on August 7, coming within 70 million miles of our planet. This likely marks the first time the comet has ever come into the inner solar system.
This comet is famous for its green color and large size, leading some people to give it the nickname "Incredible Hulk." The comet's green glow is due to cyanide and carbon molecules becoming ionized by the warmth of the sun.
The comet was discovered in September 2017. It broke up in late July as it approached the sun. And as Sky and Telescope reports, the comet has already had two eruptions ― one on June 30, and the other about two weeks later on July 16.
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