It first appeared in the year 3086.
And despite every effort made by humanity, we know as much about it now as we did then: almost nothing.
It orbits New Earth at an impossibly low altitude at a speed of 3141 kilometers per hour. Most scientists agree that it is not orbiting at all but flying or being flown, 'though no means of propulsion has been observed.
It is 941 centimeters in diameter; perfectly spherical and perfectly reflective.
And every attempt to interfere with it in any way has failed.
It flies on and on, perpetually, but it does nothing. It has been so long now that it has been all but forgotten by most of the planet's population. Even the very few scientists who still routinely check up on it do so without much interest.
But all this is about to change... Or, actually, probably it isn't. It might be that I'm just completely mad, and even if not, nobody will take me seriously: The Monosphere spoke to me today.
I heard it inside my head... Shapeless idea-thoughts, rather than words, floating in my mind... It told me its true nature, and my own as well. It said it isn't real, nor am I, nor anyone or anything in this universe. It said it (and we) only exists as a piece of art in another universe, made by an artist who also questions how "real" his own universe is and whether it even matters one way or the other.