... finding that in [the Moon] there is a provision of light and heat; also in appearance, a soil proper for habitation fully as good as ours, if not perhaps better who can say that it is not extremely probable, nay beyond doubt, that there must be inhabitants on the Moon of some kind or other?

A map of the moon... should be in every geological lecture room; for no where can we have a more complete or more magnificent illustration of volcanic operations. Our sublimest volcanoes would rank among the smaller lunar eminences; and our Etnas are but spitting furnaces.

As to what Simplicius said last, that to contend whether the parts of the Sun, Moon, or other celestial body, separated from their whole, should naturally return to it, is a vanity, for that the case is impossible, it being clear by the demonstrations of Aristotle that the celestial bodies are impassible, impenetrable, unpartable, etc., I answer that none of the conditions whereby Aristotle distinguishes the celestial bodies from the elementary has any foundation other than what he deduces from the diversity of their natural motions; so that, if it is denied that the circular motion is peculiar to celestial bodies, and affirmed instead that it is agreeable to all naturally moveable bodies, one is led by necessary confidence to say either that the attributes of generated or ungenerated, alterable or unalterable, partable or unpartable, etc., equally and commonly apply to all bodies, as well to the celestial as to the elementary, or that Aristotle has badly and erroneously deduced those from the circular motion which he has assigned to celestial bodies.

I wol yow telle, as was me taught also,
The foure spirites and the bodies sevene,
By ordre, as ofte I herde my lord hem nevene.
The firste spirit quiksilver called is,
The second orpiment, the thridde, ywis,
Sal armoniak, and the firthe brimstoon.
The bodies sevene eek, lo! hem heer anoon:
Sol gold is, and Luna silver we threpe,
Mars yron, Mercurie quiksilver we clepe,
Saturnus leed, and Jupiter is tin,
And Venus coper, by my fader kin!

Such pretensions to nicety in experiments of this nature, are truly laughable! They will be telling us some day of the WEIGHT of the MOON, even to drams, scruples and grains—nay, to the very fraction of a grain!—I wish there were infallible experiments to ascertain the quantum of brains each man possesses, and every man's integrity and candour:&mash;This is a desideratum in science which is most of all wanted.

That's one small step for a man, one giant leap for mankind.
Said as he stepped onto the Moon at 10.56 (G.M.T) on July 21st 1969. However, this is often misquoted as 'That's one small step for man, one giant leap for mankind.' This was due to static during Armstrong's transmission to earth. The 'a' was left out of his statement, ruining the contrast he had made between one man 'a man' and all mankind 'man'.

The first principles of the universe are atoms and empty space. Everything else is merely thought to exist. The worlds are unlimited. They come into being and perish. Nothing can come into being from that which is not nor pass away into that which is not. Further, the atoms are unlimited in size and number, and they are borne along in the whole universe in a vortex, and thereby generate all composite things—-fire, water, air, earth. For even these are conglomerations of given atoms. And it is because of their solidarity that these atoms are impassive and unalterable. The sun and the moon have been composed of such smooth and spherical masses [i.e. atoms], and so also the soul, which is identical with reason.

The success of Apollo was mainly due to the fact that the project was conceived and honestly presented to the public as an international sporting event and not as a contribution to science. The order of priorities in Apollo was accurately reflected by the first item to be unloaded after each landing on the Moon's surface, the television camera. The landing, the coming and going of the astronauts, the exploring of the moon's surface, the gathering of Moon rocks and the earthward departure, all were expertly choreographed with the cameras placed in the right positions to make a dramatic show on television. This was to me the great surprise of the Apollo missions. There was nothing surprising in the fact that astronauts could walk on the Moon and bring home Moon rocks. There were no big scientific surprises in the chemistry of the Moon rocks or in the results of magnetic and seismic observations that the astronauts carried out. The big surprise was the quality of the public entertainment that the missions provided. I had never expected that we would see in real time astronauts hopping around in lunar gravity and driving their Rover down the Lincoln- Lee scarp to claim a lunar speed record of eleven miles per hour. Intensive television coverage was the driving force of Apollo. Von Braun had not imagined the possibilities of television when he decided that one kilohertz would be an adequate communication bandwidth for his Mars Project.

Then if the first argument remains secure (for nobody will produce a neater one, than the length of the periodic time is a measure of the size of the spheres), the order of the orbits follows this sequence, beginning from the highest: The first and highest of all is the sphere of the fixed stars, which contains itself and all things, and is therefore motionless. It is the location of the universe, to which the motion and position of all the remaining stars is referred. For though some consider that it also changes in some respect, we shall assign another cause for its appearing to do so in our deduction of the Earth's motion. There follows Saturn, the first of the wandering stars, which completes its circuit in thirty years. After it comes Jupiter which moves in a twelve-year long revolution. Next is Mars, which goes round biennially. An annual revolution holds the fourth place, in which as we have said is contained the Earth along with the lunar sphere which is like an epicycle. In fifth place Venus returns every nine months. Lastly, Mercury holds the sixth place, making a circuit in the space of eighty days. In the middle of all is the seat of the Sun. For who in this most beautiful of temples would put this lamp in any other or better place than the one from which it can illuminate everything at the same time? Aptly indeed is he named by some the lantern of the universe, by others the mind, by others the ruler. Trismegistus called him the visible God, Sophocles' Electra, the watcher over all things. Thus indeed the Sun as if seated on a royal throne governs his household of Stars as they circle around him. Earth also is by no means cheated of the Moon's attendance, but as Aristotle says in his book On Animals the Moon has the closest affinity with the Earth. Meanwhile the Earth conceives from the Sun, and is made pregnant with annual offspring. We find, then, in this arrangement the marvellous symmetry of the universe, and a sure linking together in harmony of the motion and size of the spheres, such as could be perceived in no other way. For here one may understand, by attentive observation, why Jupiter appears to have a larger progression and retrogression than Saturn, and smaller than Mars, and again why Venus has larger ones than Mercury; why such a doubling back appears more frequently in Saturn than in Jupiter, and still more rarely in Mars and Venus than in Mercury; and furthermore why Saturn, Jupiter and Mars are nearer to the Earth when in opposition than in the region of their occultation by the Sun and re-appearance. Indeed Mars in particular at the time when it is visible throughout the night seems to equal Jupiter in size, though marked out by its reddish colour; yet it is scarcely distinguishable among stars of the second magnitude, though recognized by those who track it with careful attention. All these phenomena proceed from the same course, which lies in the motion of the Earth. But the fact that none of these phenomena appears in the fixed stars shows their immense elevation, which makes even the circle of their annual motion, or apparent motion, vanish from our eyes.

Then we upon our globe's last verge shall go,
And view the ocean leaning on the sky:
From thence our rolling Neighbours we shall know,
And on the Lunar world securely pry.

Thy shadow, Earth, from Pole to Central Sea,
Now steals along upon the Moon's meek shine
In even monochrome and curving line Of imperturbable serenity.
How shall I link such sun-cast symmetry
With the torn troubled form I know as thine,
That profile, placid as a brow divine,
With continents of moil and misery?

We came in peace for all mankind.

When the moon is ninety degrees away from the sun it sees but half the earth illuminated (the western half). For the other (the eastern half) is enveloped in night. Hence the moon itself is illuminated less brightly from the earth, and as a result its secondary light appears fainter to us.

…I distinguish two parts of it, which I call respectively the brighter and the darker. The brighter seems to suround and pervade the whole hemisphere; but the darker part, like a sort of cloud, discolours the Moon's surface and makes it appear covered with spots. Now these spots, as they are somewhat dark and of considerable size, are plain to everyone and every age has seen them, wherefore I will call them great or ancient spots, to distinguish them from other spots, smaller in size, but so thickly scattered that they sprinkle the whole surface of the Moon, but especially the brighter portion of it. These spots have never been observed by anyone before me; and from my observations of them, often repeated, I have been led to the opinion which I have expressed, namely, that I feel sure that the surface of the Moon is not perfectly smooth, free from inequalities and exactly spherical... but that, on the contrary, it is full of inequalities, uneven, full of hollows and protuberances, just like the surface of the Earth itself, which is varied everywhere by lofty mountains and deep valleys.
Describing his pioneering telecope observations of the Moon made from Jan 1610.