Balloon

There's nothing more startling than rising from your lazy couch at evening dusk, and seeing a hot air balloon landing in the field behind your garden. This baby, marked with advertisement from a technology education center in Mechelen (100m from my work !), dumped itself in a corn meadow. 5 minutes later, the companion car arrived and the great folding could begin.
Mark the dark spot above the ballon in the picture. Even at higher resolution, I have no idea if this is a bird (maybe a bit large, no ?), a blow of hot air, or a piece of venting sail from the balloon.