Asteroid close pass.

Another not so subtle warning that we need to have a plan in effect to deflect or destroy the big one.
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Bob DeWoody

I saw this just now, and thought it was worth sharing.

http://lightyears.blogs.cnn.com/2011/11/03/asteroid-to-pass-closer-to-earth-than-the-moon/?hpt=hp_t2

Steve

I saw this just now, and thought it was worth sharing.

http://lightyears.blogs.cnn.com/2011/11/03/asteroid-to-pass-closer-to-earth-than-the-moon/?hpt=hp_t2

Steve

I wounder if this asteroid passes even closer next time around.

Another not so subtle warning that we need to have a plan in effect to deflect or destroy the big one.

Several articles on this object make a point of describing it as spherical. The best image to date, made in 2010 at Arecibo radio/radar observatory shows the edge of a well rounded hemisphere, as well as a curved terminator across the middle. The effect is like that of a crescent Moon. Very surprising that an object a mere 400 meters in diameter would have sufficient gravity the form itself into a sphere, or anything approaching one. The conventional wisdom says that an object must be somewhere between 100 and 200 miles in diameter to form a sphere. We have many examples of spherical bodies, down to the size of Saturn's moon Mimas, a little over 100 miles across, but apparently none smaller. Smaller bodies, like Mars' moons, are sometimes ellipsoidal, with three different diameters in each of three dimensions. Of course these are on the order of several miles in diameter. 2005 YU55 presumably has a mass on the order of a thousandth of these.

I think the inference is that this asteroid is laden with Iron which makes it heavier than other asteroids which has allowed it to form the semi spheric shape
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Proud member of TSWB.

End terrorism by building a school

This object is very dark in color. They have been calling it C class; A 'carbonaceous chondrite'. These are made of minerals-- silicates, oxides, and sulfides, not metals. There does seem to be something unusual in it being what astronomer Dr. Paul Heckert, specialist in observational astronomy called 'very nearly spherical' and caused a writer at Sky and Telescope to call it 'remarkably round'.

Huge Asteroid Will Pass Closer To Earth Than The Moon In Coming Days


This radar image of asteroid 2005 YU55 was generated from data taken in April 2010 by the Arecibo Radar Telescope in Puerto Rico. (NASA)

Assuming it misses we will have dodged a 4,000 Megaton (of TNT) Bomb. Scary Stuff

Do the relative positions of the earth and moon during the approach affect the future trajectory of the asteroid? Some of the artwork depict it passing between the earth and the moon which will be near full. It would be neat if it crosses in front of the moon as seen from the ground.
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Bob DeWoody

The object will pass between the constellations Aquila and Pegasus when in the vicinity of Earth; well North of the ecliptic. This rules out passage in front of the Moon, from our line of sight.

Is anyone going to observe it with a telescope? I think it needs good stuff because it's small and dark and moves fast.

Is anyone going to observe it with a telescope? I think it needs good stuff because it's small and dark and moves fast.

Thank you!

It would be great but they say it's so small that it will only take some pixels on a hubble picture. But they also say it will be observed with radiotelescopes. Radio waves will be sent from Porto Rico to the asteroid, and than back to the Earth, in California. We might get a map of it. That would be so cool!

http://ciel.science-et-vie.com/2011/11/04/2011-yu55-un-gros-asteroide-va-froler-la-terre/

Sorry, it's in french.

Bienvenue, Marie. Another issue with using the Hubble Space Telescope to look at YU55 is the rapid passage of the object. The Hubble probably couldn't track it well enough to do useful work. Large optical telescopes will be used mainly for photometry and spectral analysis, rather than imaging. Several radio telescopes will be able to produce images of the object. Besides Arecibo, Goldstone, of NASA's Deep Space Network, in California, and the Byrd Observatory in West Virginia will be at work. Resolution on the order of 2 to 4 meters is anticipated. *******The unusual shape of the object is of particular interest. It's been called nearly spherical, but the preliminary shape model, made from observations at Arecibo about 18 months ago, when YU55 was much farther away, are more complex than that. From some aspects it appears spherical, but from others, cubical, or even prism-shaped. Even a sphere is hard to explain in such a small object, but these other features are even more so. If sky conditions are good enough tomorrow evening I will attempt to observe the object with my telescope. It will be a challenging task, given its dimness, ~ 11th magnitude.