@tsarstepan,
Ok. But the Blob started out as a little Bloblet in that meteor. Maybe a little bit of Blob goo clinging to a wandering asteroid is all it takes.
Actually, my main nitpick with my own selection of The Blob has to do with how such a creature (lacking technology) gets spread around the Universe enough to find it's way randomly to Earth.
Unless such organisms were to form regularly on space debris, it's unlikely they would find their way to Earth.