Well, now, this is interesting. 2010 AL30 zipped past us harmlessly about five hours ago. Because of its one-year orbital period, many people speculated it might be a manmade object, but 2010 AL30 might, in fact, be artificial-- specifically, there's a distinct possibility it could be the Fregat upper stage of the rocket that launched Venus Express to Venus. At the end he says:
Numerical backwards propagation of the orbital state of object 2010 AL30, as determined in January 2010, turns out to appear to lead to a close Venus encounter in spring 2006 and an Earth encounter in late 2005. These epochs are consistent with the Venus arrival and Earth launch dates, respectively, of ESA's Venus Express probe.
From the known approach conditions of Venus Express to Venus one can derive that a target point close above the planet's north pole, as was chosen in that mission, would lead to a deflection of an inert body on the same trajectory, such as the spent Fregat stage, that has a period of 1 year with perihelion and aphelion distances of 0.7 and 1.3 AU, respectively. These orbital parameters closely coincide with those of object 2010 AL30.
Obviously this does not constitute proof. But I would say that we have a surprisingly long chain of unusual coincidences here. Wouldn't you agree? Sadly I do not have the expertise I would need to evaluate the merits of his argument; an astronomer on the Minor Planets Mailing List posted this morning that Khan's analysis used outdated emphemerides. The Goldstone observations should be able to settle this issue.