How an Interstellar Interloper Spurred Astronomers into Action

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By Kimberly M. S. Cartier, Eos/AGU. 

Excerpt: On 1 July 2025, astronomers detected a visitor from the deep reaches of space. At the time of discovery, the object was just inside Jupiter’s orbit and was zipping across our solar system 4 times faster than the New Horizons probe sped past Pluto. It was first spotted by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Chile, which was specifically designed to spot small, fast-moving objects like this. ATLAS sent out a public, automated alert, and when astronomers saw it, they quickly went to work calculating the object’s orbit and trajectory.... 

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