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Inside the hunt for mysterious ‘twilight’ asteroids
A group of space rocks stays mostly inside the orbit of Earth, making them difficult to pick out in the glare of the sun—and potentially a threat to our planet.
The Zwicky Transient Facility's 605-megapixel field camera, fitted to a 48-inch telescope at Palomar Observatory, California, surveys the entire visible sky each night. Recently it discovered the first known asteroid to live entirely inside the orbit of Venus.
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