Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. Surprisingly, the cause of this immense structure is still debated, but is possibly related to expanding gas from a million-year old supernova . Loop I gas is impacting the nearby Aquila Rift molecular cloud , and may create relatively dense fragments of the local interstellar medium . Were our Sun to pass through one of these fragments in the next few million years, it might affect Earth's climate .
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