CELESTIAL OBSERVATIONS

it would appear distant by only two such dimensions; so that the diameter of the Moon itself appears about thirty times larger, its surface nine hundred times larger, and its solid body nearly twenty-seven thousand times larger than when it is viewed with the naked eye alone. From this, anyone may understand with sensible certainty meaning certainty derived from the senses, specifically sight that the Moon is by no means clothed in a smooth and polished surface, but is rough and uneven; and just like the face of the Earth itself, it is crowded everywhere with vast protuberances, deep chasms, and windings.

Moreover, it seems by no means of small importance to have removed disputes concerning the Galaxy, or the Milky Way original: "Galaxya, seu de Lacteo circulo", and to have made its essence manifest to the senses, and even more to the intellect. Furthermore, it will be pleasant and quite beautiful to point out the substance of the stars which every astronomer until now has called "Nebulous," and to demonstrate that it is far different from what has been believed until now.

But that which far surpasses all admiration, and which especially impelled us to provide this Warning or "Notice" to all astronomers and philosophers, is this: namely, that we have discovered four Wandering Stars original: "Quatuor Erraticas Stellas," referring to the moons of Jupiter known or observed by no one before us, which have their periods around a certain distinguished star among those already known Jupiter, just as Venus and Mercury do around the Sun, and which sometimes precede it and sometimes follow it, never departing beyond certain limits from it. All these things were discovered and observed a few days ago by means of the Spyglass original: "Perspicilli," Galileo's term for the telescope devised by me, after the light of divine grace first illuminated me.

Other perhaps more excellent things will be discovered day by day, either by me or by others, by the benefit of a similar Instrument, the form and preparation of which, as well as the occasion of its devising...