They’re from a big spider. A BIG spider. Outside of aerodave’s window. With just a flimsy screen between him and them.
Actually, the spiders’ eggs I’ve seen have been in roughly spherical silk containers. The ones in the OP are probably not spiders. (Not that I actually know; just going off of what I’ve seen before.)
Johnny, I think you might be on to something. A google image search of butterfly or moth eggs leads to results that look very similar: pale yellow or green arrays of tiny spheres closely packed.