Close Encounter with a Star
70,000 years ago a wandering star brushed by our solar system.
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70,000 years ago, a tiny Red Dwarf star visited our solar system, brushing by the outer reaches of the Oort Cloud, a mere 7.6 trillion kilometres from the sun.
That might not seem like such a close visit, but according to Dr. Eric Mamajek, an astronomer and professor at the University of Rochester, who traced the star's path, in astronomical terms that's a very close call.
Dr. Mamajek and his colleagues saw the star receding from us and traced its course backwards to discover that it was the closest known encounter of a star with our solar system. These events are relatively rare, but are important, as a close flyby can potentially disturb the orbits of comets and the outer planets, and lead to cosmic collisions.
Related Links
- Paper in The Astrophysical Journal Letters
- Dr. Mamajek's FAQ on the encounter
- University of Rochester release
- Sky and Telescope story
- BBC News story