Asteroid 2004 BL86 traveled by Earth January 26, 2015. It was about 3x farther from Earth than our Moon. There was no danger. It was an interesting event. It happened during the daylight hours for me. It was also clouded over. There was no chance to see it with my own equipment. So, I visited an online broadcast from Europe. The Virtual Telescope Project successfully tracked it.
The event was hosted by Gian Masi, astrophysicist and science communicator. They posted a 28 minute YouTube video. Broken clouds interrupted the view at times. Their telescope tracked the asteroid at the center of the window. A 10 second time exposure captured an image. Each 15 seconds, a new image was scanned over the old one. The asteroid remains centered. The star field moves slightly. I extracted a brief clip from one cloud-free interval if you don’t want to watch the entire video. This object was moving very fast. It traveled the equivalent of 5 Moon diameters each hour.
Fellow blogger, Alex Autin, posted on …Things I Love more exciting information about this asteroid. It has a moon! Visit her site. If you like astronomy, follow her blog. Radar images from the 230-foot-wide NASA Deep Space Network antenna at Goldstone, California, revealed the moon to be about 230 feet wide. The asteroid is about 1100 feet wide. The full video is on her site or here at the NASA JPL YouTube channel.