Large asteroid zipping past Earth, dragging its own moon along

[CleveSteve]

That picture is a little confusing. The OP says the asteroid's "moon" is 2,000 feet in diamater, or 0.38 miles. The asteroid is 1.7 miles wide. The "moon" should be about 1/4 to 1/5 the diameter of the main asteroid, but it looks like a blip in the pictures. I think the term also floated in that article "binary asteroid" is more apropos if the size reported is correct.