Thomas Malthus Quotes

If the moon and earth were not retained in their orbits by their animal force or some other equivalent, the earth would mount to the moon by a fifty-fourth part of their distance, and the moon fall towards the earth through the other fifty-three parts, and they would there meet, assuming, however, that the substance of both is of the same density.

Planets' orbits are elliptical. It's a very pleasing shape.

We all know we fall. Newton's discovery was that the moon falls, too-and by the same rule that we do.

And the earth self-balanced on her centre hung.

Thus far I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity. Indeed, this force arises from some cause that penetrates as far as the centers of the sun and planets without any diminution of its power to act, and that acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter, and whose action is extended everywhere to immense distances, always decreasing as the squares of the distances.

What's the orbital velocity of the moon?

Gravity explains the motions of the planets, but it cannot explain who sets the planets in motion.

Every particle of matter is attracted by or gravitates to every other particle of matter with a force inversely proportional to the squares of their distances.

I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity.

What really made me think about space and begin to think about ways to use it was Einstein's statement that there are no fixed points in space. Everything in the universe is moving all the time.

Do not Bodies act upon Light at a distance, and by their action bend its Rays; and is not this action (caeteris paribus) [all else being equal] strongest at the least distance?

They have likewise discovered two lesser stars, or satellites, which revolve around Mars, whereof the innermost is distant from the center of the primary exactly three of his diameters, and the outermost five: the former revolves in the space of ten hours, and the latter in twenty-one and a half, so that the squares of their periodical times are very near in the same proportion with the cubes of their distances from the center of Mars; which evidently shows them to be governed by the same Law of Gravitation that influences the other heavenly bodies.

Bullialdus wrote that all force respecting ye Sun as its center & depending on matter must be reciprocally in a duplicate ratio of ye distance from ye center.

I am sitting here 93 million miles from the sun on a rounded rock which is spinning at the rate of 1000 miles an hour... and my head pointing down into space with nothing between me and infinity but something called gravity which I can't even understand, and which you can't even buy any place so as to have some stored away for a gravityless day.

The squares of the periodic times are proportional to the cubes of the mean distances from the sun.

Either... the moving intelligences of the planets are weakest in those that are farthest from the sun, or... there is one moving intelligence in the sun, the common center, forcing them all round, but those most violently which are nearest, and that it languishes in some sort and grows weaker at the most distant, because of the remoteness and the attenuation of the virtue.

I shall now recall to mind that the motion of the heavenly bodies is circular, since the motion appropriate to a sphere is rotation in a circle.

Benjamin Franklin maintained that every star is a sun, and every sun nourishes a 'chorus of worlds' just like ours.

Just as the system of the sun, planets and comets is put in motion by the forces of gravity, and its parts persist in their motions, so the smaller systems of bodies also seem to be set in motion by other forces and their particles to be variously moved in relation to each other and, especially, by the electric force.

I've been studying the planets and learning the personalities of each planet.

I'm working to bring celestial objects like the sun and moon into the spaces that we inhabit.

There is still some gravity where we are and even as far out as our moon. That is why our moon stays in orbit around the Earth. We don't feel the gravity up here because it is so much smaller than the force we feel when we are on the Earth.

The questions that we scientist have about Saturn's rings are the questions that an ordinary person might be moved to ask when first seeing them, you know. What caused them? How did they get there? How long have they been around? How long are they going to last?

Planets look about the same here as they do to you on the Earth because we really aren't that much closer. Our home, the International Space Station, orbits around the Earth at about 200 miles.

I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.