2005 YU55 Nasa pictures

2005 YU55 Nasa pictures

2005 YU55 Nasa pictures, At 6:38 p.m. ET on Tuesday, a 400-meter wide asteroid made its closest approach to Earth, passing below the orbit of the moon. Although asteroid 2005 YU55 came no closer than 201,000 miles -- a very comfortable distance, mind you, with zero chance of actually hitting Earth -- from our atmosphere, this is the largest near-Earth object on record to come so close to our planet.


Astronomers were tracking the asteroid's progress closely from numerous observatories around the globe (including the the infrared Keck Observatory in Hawaii), mostly using radar technology to capture this rare "up close and personal" moment for posterity. Per Phil Plait at Bad Astronomy:

[T]hose radio telescopes can be used like radar guns, sending out short pulses of focused radio waves. These pulses are aimed at the asteroid and move at the speed of light, hitting the rock and bouncing back. Since we know the speed of light very accurately, we can measure the time it takes a pulse to get to the asteroid and back, multiply it by the speed of light, and get the distance... The individual pulses can be timed very accurately as well, so that the shape of the asteroid can be determined, too.

Oh, and Plait would like you to know that asteroid YU55 had nothing whatsoever to do with last Saturday's earthquake in Oklahoma. Just for the record.

Meanwhile, at the 70-meter Deep Space Network antenna in Goldstone, California, the team of astronomers decided to animate an entire sequence of their high-resolution radar images of YU55 to make a short movie clip. (Suggested title: "The Asteroid's Progress.") It was painstaking work: each of the six frames required a full 20 minutes of data collection by the radar equipment at Goldstone.

But the work paid off, according to JPL radar astronomer Lance Brenner, who led the YU55 observation effort, since they were able to see much more surface detail than would have been visible otherwise.

Specifically, "The animation reveals a number of puzzling structures on the surface that we don't yet understand," he said in the official press release. "To date, we've seen less than one half of the surface, so we expect more surprises."

Radar wasn't the only tool used to snap "pictures" of YU55. The Keck Telescope successfully achieved the first infrared observation of the asteroid, too. Once the Keck II telescope locked onto its target, it took just one second to capture enough infrared photons to create an image. Maybe Keck and make their own animated short. Infrared also makes for some pretty pictures.

Source: discovery