“The women excrete human germs every four weeks. First, for a very short time, they are devoted to the moon influence. There they are protected. Now, however, the female organism is arranged so that it carries outwards the human germ. Since the seed comes under the influence of earth, the earths influence destroys the human germ.
Constantly, such unfertilized germs are going away from the earth to the space beyond. So if, for example, someone might perceive such a thing, and he would sit on top of Venus, then the ascending vapors would not interest him.
But what continually goes up into space, he would see above as a greenish-yellow light; because seen from afar it is a kind of greenish-yellow light. And he would find that the light comes out of some kind of world body.” (Rudolf Steiner)
Source: Rudolf Steiner – “LECTURES FOR WORKERS AT THE GOETHEANUM CONSTRUCTION SITE”, complete works volume 348 (GA 348, page 144).