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After I had addressed myself to this very difficult and almost insoluble problem, the suggestion at length came to me how it could be solved with fewer and much simpler constructions than were formally used, if some assumptions (which are called axioms) were granted me. They follow in this order. There is no one…
In the year 1666 he retired again from Cambridge... to his mother in Lincolnshire & whilst he was musing in a garden it came into his thought that the power of gravity (wch brought an apple from the tree to the ground) was not limited to a certain distance from the earth but that this power must extend much farther…
Newton supposed that the case of the planet was similar to that of [a ball spun around on the end of an elastic string]; that it was always pulled in the direction of the sun, and that this attraction or pulling of the sun produced the revolution of the planet, in the same way that the traction or pulling of the…
When Newton saw an apple fall, he found In that slight startle from his contemplation— 'Tis said (for I'll not answer above ground For any sage's creed or calculation)— A mode of proving that the earth turn'd round In a most natural whirl, called 'gravitation'; And this is the sole mortal who could grapple, Since…
To a body of infinite size there can be ascribed neither center nor boundary ... Just as we regard ourselves as at the center of that universally equidistant circle, which is the great horizon and the limit of our own encircling ethereal region, so doubtless the inhabitants of the moon believe themselves to be at the…
It may seem rash indeed to draw conclusions valid for the whole universe from what we can see from the small corner to which we are confined. Who knows that the whole visible universe is not like a drop of water at the surface of the earth? Inhabitants of that drop of water, as small relative to it as we are relative…
Copernicus, who rightly did condemn This eldest systeme, form'd a wiser scheme; In which he leaves the Sun at Rest, and rolls The Orb Terrestial on its proper Poles; Which makes the Night and Day by this Career, And by its slow and crooked Course the Year. The famous Dane, who oft the Modern guides, To Earth and Sun…
All the knowledge we possess of external objects is founded upon experience, which furnishes facts; and the comparison of these facts establishes relations, from which induction, the intuitive belief that like causes will produce like effects, leads to general laws. Thus, experience teaches that bodies fall at the…
Ravna had known that “jumpstarting” technology must be a topic in the ship’s library. It turned out the subject was a major academic specialty. Besides ten thousand case studies, there were customizing programs and lots of very dull-looking theory. Though the “rediscovery problem” was trivial in the Beyond, down in…
The young John Keats remembered an organised game at his school in Enfield, in which all the boys whirled round the playground in a huge choreographed dance, trying to imitate the entire solar system, including all the known moons (to which Herschel had by then added considerably). Unlike Newton’s perfect brassy…
The disappearance of the traditional world of the ‘four elements’ was revolutionary. It was as radical in the world of chemistry as Copernicus’s proof that the earth was not the centre of the solar system; or (some said) as Robespierre’s claim that the people, not the king, embodied sovereignty. Moreover, it was…
Sometime in the summer of 1786 the fifty-year-old John Adams, graduate of Harvard University, man of science and future second President of the United States, turned up one morning uninvited at The Grove. He was shown round all Herschel’s new telescopes, and they embarked on an impassioned discussion of the…
The mathematician Freeman Dyson, of the Institute for Advanced Study, offers a scheme in which the planet Jupiter is broken down piece by piece, transported to the distance of the Earth from the Sun, and reconstructed into a spherical shell – a swarm of individual fragments revolving about the Sun. The advantage of…
There is a place with four suns in the sky – red, white, blue, and yellow; two of them are so close together that they touch, and star-stuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth – and made of diamond. There are atomic nuclei a mile across that rotate thirty…
There was a time – and very recently – when the idea of the possibility of learning the composition of the celestial bodies was considered senseless even by prominent scientists and thinkers. That time has now passed. The idea of the possibility of a closer, direct study of the universe will today, I believe, appear…
It is possible to speculate on the very distant future of advanced civilizations. We can imagine such societies in excellent harmony with their environments, their biology, and the vagaries of their politics, so that they enjoy extraordinarily long lifetimes. Communications would long have been established with many…
Pioneer 10 is the first interstellar spacecraft launched by mankind. It was also the fastest spacecraft launched, to the date of its departure. But it will take eighty thousand years for Pioneer 10 to reach the distance of the nearest star. Because space is so empty, it will never enter another Solar System. The…
The Solar System is much vaster than the Earth, but the speeds of our spacecraft are, of course, much greater than the speeds of the sailing ships of the fifteenth and sixteenth centuries. The spacecraft trip from the Earth to the Moon is faster than was the galleon trip from Spain to the Canary Islands. The voyage…
In all the history of mankind, there will be only one generation that will be first to explore the Solar System, one generation for which, in childhood, the planets are distant and indistinct discs moving through the night sky, and for which, in old age, the planets are places, diverse new worlds in the course of…
On the title page of this chapter is shown the message. It is etched on a 6-inch by 9-inch gold-anodized aluminum plate, attached to the antenna support struts of Pioneer 10. The expected erosion rate in interstellar space is sufficiently small that this message should remain intact for hundreds of millions of years…