389E-426-Rose Rules Again Recently my Catalina Sky Survey teammate Rose Matheny discovered 8 new Earth approaching object candidates on a single night with our Schmidt telescope on Mt. Bigelow, Arizona. One of them, 2017 YO is a mile and a half diameter, main belt asteroid, while the other 7 are interesting Earth approaching objects. Another one of Rose's single night discoveries is 2017 YM1. When Rose first spotted it this space rock was moving rapidly north, at 6.9 miles per second, away from the Earth in the constellation of Ursae Major. About 5 days earlier it had passed near both the Earth and Our Moon at which time it was too far south to be seen from Arizona. This space rock is about 92 feet in diameter, orbits the Sun once every 2.25 years, and can come to less than a tenth of the Moon's distance from us. 2017 YM1 is about 1.5 times larger than the Chelyabinsk (Shell ya binsk) meteor which in 2013 broke many thousands of windows and injured 1,200 people. According to Perdue University's impact calculator, a space rock like 2017 YM1 enters the Earth's atmosphere once every hundred years or so with an energy of 250 kilotons of TNT, explodes into a cloud of fragments at about 73,000 feet, rains pieces onto the ground, and produces a sonic boom that would get your attention as it breaks a lot of windows. Asteroid hunter's goal is to discover any such impactor days before it enters the Earth's atmosphere so that people can be warned to stay away from doors and windows. For Travelers in the Night this is Dr. Al Grauer.

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