This GIF shows asteroid 2004 BL86, which safely flew past Earth on Jan. 26, 2015. Seen in the image is a small moon trailing the minor planet. Image courtesy of NASA/JPL-Caltech
Earth’s close encounter with Asteroid 2004 BL86 on Monday revealed that the massive space object had a traveling companion: its own moon.
The asteroid, measuring 1,100 feet across, posed no threat as it came within 745,000 miles of Earth, the closest distance a known asteroid of that size will make again for at least another two centuries.
NASA’s Deep Space Network antenna in Goldstone, California, captured images of Monday’s flyby, including those of 2004 BL86′s moon, which is 230 feet across. Among the space rocks that buzz by our planet, 2004 BL86 is part a group of asteroids classified as a “binary system.”
“In the near-Earth population, about 16 percent of asteroids that are about 655 feet (200 meters) or larger are a binary (the primary asteroid with a smaller asteroid moon orbiting it) or even triple systems (two moons),” NASA’s Jet Propulsion Laboratory said
Earth won’t see another asteroid of similar size until Asteroid 1999 AN10 floats past the planet in 2027.
The post In Earth flyby, massive asteroid reveals a moon of its own appeared first on PBS NewsHour.