Two asteroids to pass within moon’s distance

Two asteroids, several meters in diameter and in unrelated orbits, will pass within the moon’s distance of Earth on Wednesday, September 8.

Neither of these objects has a chance of hitting Earth, according to NASA, which issued a press release about the event on the afternoon of September 7. Since both objects have been given preliminary designations, we can assume they were previously unknown.

Near-Earth asteroid 2010 RX30 is estimated to be 32 to 65 feet (10 to 20 meters) in size and will pass within 0.6 lunar distances of Earth (about 154,000 miles, or 248,000 kilometers) at 2:51 a.m. PDT (5:51a.m. EDT) Wednesday.

The second object, 2010 RF12, estimated to be 20-46 feet (6 to 14 meters) in size, will pass within 0.2 lunar distances (about 49,088 miles or 79,000 kilometers) a few hours later at 2:12 p.m. PDT (5:12 pm EDT).

The Catalina Sky Survey near Tucson, Arizona, discovered both objects on the morning of Sunday, September 5, during their routine monitoring of the skies. The Minor Planet Center in Cambridge, Mass., first received the observations Sunday morning, determined preliminary orbits and concluded that both objects would pass within the distance of the moon about three days after their discovery.

According to NASA, both asteroids should be observable near closest approach with moderate-sized amateur telescopes.

NASA says it will have a TV downlink, schedule and streaming video information here, but it was not available when I clicked just now.

NASA says that a 10-meter-sized near-Earth asteroid – such as these two – from an estimated population of about 50 million undiscovered asteroids should be expected to pass almost daily within a lunar distance. NASA says one might strike Earth’s atmosphere about every 10 years on average. So even if one of these did strike … it’s nothing that has not happened before, many times. I’m not sure why they issued this press release if it’s something that happens daily. Perhaps they do not detect them daily. Or perhaps it is unusual to see two at once.

In either case, we’ll update if we get more about the two asteroids expected to pass within the moon’s distance on September 8.