Hipparchus Quotes

It is to these two discoveries by Bradley that we owe the exactness of modern astronomy. .... This double service assures to their discoverer the most distinguished place (after Hipparchus and Kepler) above the greatest astronomers of all ages and all countries.

What the Greek called Kosmos was the image of a world that is not continuous but complete. Inevitably, then, the Greek man himself was not a series but a term. What his philosophers occasionally told him on the subject they had heard, not experienced, and what a few brilliant minds in the Asiatic-Greek cities (such as Hipparchus and Aristarchus) discovered was rejected alike by the Stoic and by the Aristotelian, and outside a small professional circle not even noticed.

Keep this constantly in mind: that all sorts of people have died—all professions, all nationalities. Follow the thought all the way down to Philistion, Phoebus, and Origanion. Now extend it to other species. We have to go there too, where all of them have already gone: . . . the eloquent and the wise—Heraclitus, Pythagoras, Socrates . . . . . . the heroes of old, the soldiers and kings who followed them . . . . . . Eudoxus, Hipparchus, Archimedes . . . . . . the smart, the generous, the hardworking, the cunning, the selfish . . . . . . and even Menippus and his cohorts, who laughed at thewhole brief, fragile business. All underground for a long time now. And what harm does it do them? Or the others either—the ones whose names we don’t even know? The only thing that isn’t worthless: to live this life out truthfully and rightly. And be patient with those who don’t.

54. Long before either wave or particle, some (Pythagoras, Euclid, Hipparchus) thought that our eyes emitted some kind of substance that illuminated, or "felt," what we saw. (Aristotle pointed out that this hypothesis runs into trouble at night, as objects become invisible despite the eyes' purported power.) Others, like Epicurus, proposed the inverse--that objects themselves project a kind of ray that reaches out toward the eye, as if they were looking at us (and surely some of them are). Plato split the difference, and postulated that a "visual fire" burns between our eyes and that which they behold. This still seems fair enough.

In light of Hipparchus and Ptolemy’s extraordinarily successful predictive theories, the goal of astronomy was to find the right combination of circles to describe the motion of the heavenly bodies around the Earth. Contrary to expectations, it turned out that Earth was itself one of the heavenly bodies. After Copernicus, the goal appeared to be to find the right combination of moving spheres that would reproduce the motion of the planets around the Sun. Contrary to expectations, it turned out that abstract elliptical trajectories were better than spheres. After Newton, it seemed clear that the aim of physics was to find the forces acting on bodies. Contrary to this, it turned out that the world could be better described by dynamical fields rather than bodies. After Faraday and Maxwell, it was clear that physics had to find laws of motion in space, as time passes. Contrary to assumptions, it turned out that space and time are themselves dynamical. After Einstein, it became clear that physics must only search for the deterministic laws of Nature. But it turned out that we can at best give probabilistic laws. And so on. Here are some sliding definitions for what scientists have thought science to be: deduction of general laws from observed phenomena, finding out the ultimate constituents of Nature, accounting for regularities in empirical observations, finding provisional conceptual schemes for making sense of the world. (The last one is the one I like.) Science is not a project with a methodology written in stone, or a fixed conceptual structure. It is our ever-evolving endeavor to better understand the world. In the course of its development, it has repeatedly violated its own rules and its own stated methodological assumptions.

We do not know whether [Hipparchus] drew maps--perhaps he did--but the truth is that in his day he could not possibly have applied his projections to the globe because the necessary data, in the form of correct findings of latitudes and longitudes of a very large number of places over the known areas of the earth, were not available. This was the weakness of all Greek cartographic science. In Greek times mathematics was in advance of mechanical instrumentation: There was no instrument for easily and correctly determining the longitude of places. However, the Piri Re'is and the other maps we went on to study, seemed to suggest that such an instrument or instruments had once existed, and had been used by people who knew very closely the correct size of the earth. Moreover, it looks as if this people had visited most of the earth. They seem to have been quite well acquainted with the Americas, and to have mapped the coasts of Antarctica.

It is ascertained that the eclipses complete their whole revolution in the space of 223 months, that the eclipse of the sun takes place only at the conclusion or the commencement of a lunation, which is termed conjunction, while an eclipse of the moon takes place only when she is at the full, and is always a little farther advanced than the preceding eclipse. Now there are eclipses of both these stars in every year, which take place below the earth, at stated days and hours; and when they are above it they are not always visible, sometimes on account of the clouds, but more frequently, from the globe of the earth being opposed to the vault of the heavens. It was discovered two hundred years ago, by the sagacity of Hipparchus, that the moon is sometimes eclipsed after an interval of five months, and the sun after an interval of seven; also, that he becomes invisible, while above the horizon, twice in every thirty days, but that this is seen in different places at different times. But the most wonderful circumstance is, that while it is admitted that the moon is darkened by the shadow of the earth, this occurs at one time on its western, and at another time on its eastern side. And farther, that although, after the rising of the sun, that darkening shadow ought to be below the earth, yet it has once happened, that the moon has been eclipsed in the west, while both the luminaries have been above the horizon. And as to their both being invisible in the space of fifteen days, this very thing happened while the Vespasians were emperors, the father being consul for the third time, and the son for the second.   Detailed table of contents

Greek astronomer Hipparchus compiled the first star catalog, in the second century B.C.

The 1º shift was discovered by the Greek astronomer, Hipparchus (190 - 120 BC). He found that the Equinox moved 1º retrograde, or backwards. In other words, 0°Aries once coincided with the actual position of the constellation of Aries on the very first day of Spring. Now this occurs in the Sign of Pisces. Hipparchus realised that the horoscope needed to be anchored somewhere, so he invented the Tropical Zodiac. This means that 0º Aries is permanently anchored in the zodiac at a single point, the day of the Spring Equinox.

Why did Hipparchus look upward and name the stars while tens of thousands of others slept? What compelled Archimedes to calculate the mathematical properties of spirals and spheres, or Gauss to approach infinity and presume to grapple with it? They had imaginative and audacious minds, certainly. But they also had passion and energy; they took joy in discovering something new. Nature rewards the enthusiastic and curious with excitement in the chase and the thrill of discovery, rewards the intellectually playful with the exuberant pleasures of play. Exuberance in science drives exploration and sustains the quest; it brings its own Champagne to the discovery.