“The article indicates how three facts concerning the long-period comets, which hitherto were not well understood, namely the random distribution of orbital planes and of perihelions, and the preponderance of nearly-parabolic orbits, may be considered as necessary consequences of the perturbations acting on the comets.”

— Jan Oort

[The structure of the cloud of comets surrounding the Solar System and a hypothesis concerning its origin, Bulletin of the Astronomical Institutes of the Netherlands, 11, 408, 91–110, 3 January 1950, 91, https://openaccess.leidenuniv.nl/bitstream/handle/1887/6036/BAN_11_91_110.pdf?sequence=1] (quote from p. 91)

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Jan Oort 5

Dutch astronomer 1900–1992

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“From a score of well-observed original orbits it is shown that the "new" long-period comets generally come from regions between about 50000 and 150000 A. U. distance. The sun must be surrounded by a general cloud of comets with a radius of this order, containing about 1011 comets of observable size; the total mass of the cloud is estimated to be of the order of 1/10 to 1/100 of that of the earth. Through the action of the stars fresh comets are continually being carried from this cloud into the vicinity of the sun.”

Jan Oort (1900–1992) Dutch astronomer

“He cou'd foretel whats'ever was
By consequence to come to pass;
As death of great men, alterations,
Diseases, battles, inundations.
All this, without th' eclipse o' th' sun,
Or dreadful comet, he hath done,
By inward light; away as good,
And easy to be understood;”

Samuel Butler (poet) Hudibras

Hudibras, Part I (1663–1664)
Context: He cou'd foretel whats'ever was
By consequence to come to pass;
As death of great men, alterations,
Diseases, battles, inundations.
All this, without th' eclipse o' th' sun,
Or dreadful comet, he hath done,
By inward light; away as good,
And easy to be understood;
But with more lucky hit than those
That use to make the stars depose,
Like Knights o' th' post, and falsely charge
Upon themselves what others forge:
As if they were consenting to
All mischiefs in the world men do:
Or, like the Devil, did tempt and sway 'em
To rogueries, and then betray 'em.

“Heisenberg’s starting point was the philosophical judgment, that a physical theory should not concern itself with things like electron orbits in atoms that can never be observed. This is a risky assumption, but in this case it served Heisenberg well.”

Steven Weinberg (1933) American theoretical physicist

Source: Lectures on Quantum Mechanics (2012, 2nd ed. 2015), Ch. 1: Historical Introduction

“If we suppose the distance of the fixed stars from the sun to be so great that the diameter of the earth's orbit viewed from them would not subtend a sensible angle, or which amounts to the same, that their annual parallax is quite insensible; it will then follow that a line drawn from the earth in any part of its orbit to a fixed star, will always, as to sense, make the same angle with the plane of the ecliptic, and the place of the star, as seen from the earth, would be the same as seen from the sun placed in the focus of the ellipsis described by the earth in its annual revolution, which place may therefore be called its true or real place.
But if we further suppose that the velocity of the earth in its orbit bears any sensible proportion to the velocity with which light is propagated, it will thence follow that the fixed stars (though removed too far off to be subject to a parallax on account of distance) will nevertheless be liable to an aberration, or a kind of parallax, on account of the relative velocity between light and the earth in its annual motion.
For if we conceive, as before, the true place of any star to be that in which it would appear viewed from the sun, the visible place to a spectator moving along with the earth, will be always different from its true, the star perpetually appearing out of its true place more or less, according as the velocity of the earth in its orbit is greater or less; so that when the earth is in its perihelion, the star will appear farthest distant from its true place, and nearest to it when the earth is in its aphelion; and the apparent distance in the former case will be to that in the latter in the reciprocal proportion of the distances of the earth in its perihelion and its aphelion. When the earth is in any other part of its orbit, its velocity being always in the reciprocal proportion of the perpendicular let fall from the sun to the tangent of the ellipse at that point where the earth is, or in the direct proportion of the perpendicular let fall upon the same tangent from the other focus, it thence follows that the apparent distance of a star from its true place, will be always as the perpendicular let fall from the upper focus upon the tangent of the ellipse. And hence it will be found likewise, that (supposing a plane passing through the star parallel to the earth's orbit) the locus or visible place of the star on that plane will always be in the circumference of a circle, its true place being in that diameter of it which is parallel to the shorter axis of the earth's orbit, in a point that divides that diameter into two parts, bearing the same proportion to each other, as the greatest and least distances of the earth from the sun.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), Demonstration of the Rules relating to the Apparent Motion of the Fixed Stars upon account of the Motion of Light.

“It is not necessary to retain facts that we may reason concerning them.”

Pierre Beaumarchais The Barber of Seville

Il n'est pas nécessaire de tenir les choses pour en raisonner.
Act V, scene iv. Reported in Hoyt's New Cyclopedia Of Practical Quotations (1922), p. 658-59.
Le Barbier de Séville (1773)

“As I approach my 90th birthday, my friends are asking how it feels like, to have completed 90 orbits around the Sun. Well, I actually don't feel a day older than 89!”

Arthur C. Clarke (1917–2008) British science fiction writer, science writer, inventor, undersea explorer, and television series host

90th Birthday Reflections (2007)

“The bases of music are rhythm and harmony. Rhythm is ordered recurrence in time… As the planets move around the sun, they repeat their orbits periodically; thus there is already a primitive kind of rhythm in their motion. …Harmony …can be considered a special kind of rhythm. …pure musical tones are produced when the vibrations are… periodic or… repeat themselves regularly in time. Two tones harmonize if their intervals of repetition are in rhythm—or, in mathematical language, if their periods are in proportion.”

Frank Wilczek (1951) physicist

Kepler... in the third book of Harmonice mundi... attempted to make other... related, connections between musical harmony and mathematical proportion.
Longing for the Harmonies: Themes and Variations from Modern Physics (1987)

“History must be this or it is nothing. Every law which the state enacts indicates a fact in human nature; that is all. We must in ourselves see the necessary reason of every fact, — see how it could and must be.”

Ralph Waldo Emerson (1803–1882) American philosopher, essayist, and poet

1840s, Essays: First Series (1841), History

“We clothe ourselves in flame
And trade new myths for old.
The Greek gods christen us
With ghosts of comet swords;
God smiles and names us thus:
Arise! Run! Fly, my Lords!”

Ray Bradbury (1920–2012) American writer

"We March Back to Olympus" in Where Robot Mice and Robot Men Run Round in Robot Towns (1977), p. 11

“No religious position is loyally served by refusing to consider annoying theories which may well turn out to be facts.”

Norman Lamm (1927) American rabbi

Seventy faces: articles of faith (2002)

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Jan Oort 5

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