[detaro]

Is this really something they could effectively hide otherwise from other space powers? If not, telling the world about it doesn't hurt much, is good PR, might make running the mission easier (if it was known during the flight and coordinated with other users of space), and the question of what it did is probably more interesting anyways.

EDIT: looked it up a bit: both the start of this and previous missions had media coverage, and amateurs temporarily tracked the plane, so no point in secrecy.