The mysterious case of the missing asteroid.

[RGClark]

Lost in space: Massive asteroid goes missing, amateur sky-watchers asked to find it
By Scott Sutherland | Geekquinox – Wed, 19 Feb, 2014

Uh oh! It seems that we have an AWOL asteroid on our hands!
On Monday night, an asteroid roughly the size of three football fields — named 2000 EM26 — was supposed to fly by Earth. Astronomers with the Slooh Space Camera site trained their robotic telescope onto the location in the sky where the asteroid was supposed to be, so they could live-broadcast the flyby to everyone over the web. However, instead of seeing the asteroid show up as a bright, steady point of light among the trailing background stars, all they saw were the stars themselves. The asteroid was missing!
ca.news.yahoo.com/blogs/geekquinox/lost-space-massive-asteroid-2000-em26-pulls-vanishing-162625767.html

Bob Clark

 

[MattBaker]

An asteroid with an obversation arc of 9 days isn't at the exact place you want it to be. An object with such a high orbital uncertainty is often "missing".