A newly discovered asteroid designated 2017 UK8 flew past Earth at 0.59 LD / 0.00151 AU (~ 225 892km / 140 363 miles) at 05:17 UTC on October 30, 2017. This is the 46th known near-Earth asteroid to flyby Earth within 1 lunar distance since the start of year, and 11th this month, making October the only month this year with as much as 11 such flybys.
2017 UK8 belongs to the Apollo group of asteroids, those whose orbits cross the Earth's orbit similar to that of 1862 Apollo (a > 1.0 au ; q < 1.017 au ). It was first observed at Catalina Sky Survey on October 29, one day before its close approach.
This asteroid has an estimated diameter between 5.1 and 11 m (16 - 36 feet) and it flew past Earth at a speed (relative to the Earth) of 14.07 km/s at 05:17 UTC.
This is the 46th known near-Earth asteroid to flyby Earth within 1 lunar distance this year, and 11th this month, making October the only month this year with as much as 11 such flybys (according to data available October 30). Months that came nearly as close as October were March, with 9 such flybys, and September, with 8.
In the past 57 days (2 months; September & October), we had 19 known asteroid flybys within 1 lunar distance (of 46 total in 10 months).
Featured image: The green line indicates the object's apparent motion relative to the Earth, and the bright green marks are the object's location at approximately one-hour intervals. The Moon's orbit is grey. The blue arrow points in the direction of Earth's motion and the yellow arrow points toward the Sun. Credit: Minor Planet Center.