Why heavenly bodies are sperical in nature?

Answer 1

Bodies beyond a certain mass are spherical due to the nature of gravity which pulls them together. But there are many asteroids and comets that are small and irregularly shaped because gravity can not overcom the strength of the material.

Answer 2

Gee, I sure don't think they're spherical. I, being a male of the genus and species Homo Sapiens, tend to think of heavenly bodies of a somewhat different shape. A-a-a-h-h-h.

Answer 3

Hi. They are roughly spherical because gravity pulls toward the center of mass. Any high point gets pulled down.

Answer 4

Problems with the Aristotelian Worldview

Central components of the Aristotelian worldview?
earth is spherical
stationary
center of the universe
heavenly bodies move in perfect circles
uniform motion
five elements (earth, air, fire, water, ether)
the principle of motion (things will come to a stop unless something moves them)
sphere of stars at edge of universe
the universe is rather small
the behavior of thrown objects
sublunar and superlunar regions
perfection of the heavens
Conceptual beliefs of the Aristotelian worldview?

everything in the universe has an essential nature
everything has an ultimate goal or end, everything has a function
there is a god (or gods)
essence organizes the matter
everything in the universe has a natural motion which depends upon what they’re made of (earth, air, fire, water, ether)
essential nature of the five elements
earth: center of the universe
air: to move outward
fire: to move to the edges of the universe
water: move to center of the universe but is on top of the earth
ether: perfect spherical shape, moves in perfect circles, in the superlunar region, desires to be like the gods
uniform motion
perfect circularity
How do the different conceptual beliefs interact to shape the Aristotelian worldview? What explanations for various phenomena rely on conceptual beliefs?

it’s because of the essential nature of ether (and the heavenly bodies being made of ether) that the heavenly bodies move in perfect circularity
earth is at the center of the universe because it is made of earth
we stay on the earth because we’re composed partially of earth
the earth doesn’t move because there’s nothing to push it (principle of motion)
Arguments in favor of the Aristotelian worldview?

empirical evidence supports these claims
stellar parallax is not observed
scriptures
we don’t feel breeze
we don’t fly off of the earth
things don’t land behind us
earth, because it has a tendency to move to the center of the universe, will probably take the shape of a sphere and not a cube or triangle
heavenly bodies rise earlier for those on the east than those on the west
mountains seem to ‘rise up’ out of the water
there are different stars in the north and south
What are some of the crucial discoveries or arguments made by Copernicus, Tycho, Kepler, and Galileo?

the sun is the center of the universe
the planets orbit in an elliptical pattern
imperfect sun and moon
planets orbit and different speeds
Jupiter has moons
Saturn has ‘ears’
Venus and Mercury has phases
Universe is HUGE
Planets orbit around the sun
There’s a relation between the orbital period of the planets and their distance from the sun
How do these discoveries/systems undermine various components of the Aristotelian worldview?

The planets don’t orbit in perfect circles
The heavens aren’t perfect
The earth isn’t the center of the universe
The five elements are no longer supported
Ether doesn’t exist (moon has mountains, heavens aren’t perfect, planets orbit in ellipses
Terra, because it isn’t the center of the universe, undermines the idea that dirt naturally goes to the center of the universe
No epicycles/no perfect circularity
No explanation for why rocks fall
No explanation for why things move – ether is problematic…and the earth moves
Universe is absolutely massive…not rather small
Sun centered universe
Since the earth moves and we still don’t observe a parallax, the stars must be absolutely HUGE distances away from us
Behavior of thrown objects is wrong…the ball really does move in an arc
No need for a sphere of stars

Philosophical and Conceptual Connections in the Development of the New Science

The universe is vast.
Why? How do we know (how did those in Newton’s time know) that the universe is inconceivably large?

This idea was made more palatable by the philosophers Nicholas de Cusa and Giordano Bruno

Bruno:

This entire globe, this star, not being subject to death, and dissolution and annihilation being impossible anywhere in Nature, from time to time renews itself by changing and altering all its parts. There is no absolute up or down, as Aristotle taught; no absolute position in space; but the position of a body is relative to that of other bodies. Everywhere there is incessant relative change in position throughout the universe, and the observer is always at the centre of things.

Nicholas de Cusa’s views about the universe as infinite stemmed from his neoplatonic views of God and all of nature as well as his views about the nature of knowledge. He, like Giordino Bruno, held that the universe is infinite and there were infinite number of worlds in the universe.

Both Bruno and de Cusa were connected to another philosophic tradition called atomism.

Atomism: the belief that the universe is infinite and all that it is in the universe are atoms (imperceptible, indivisible particles) falling through the void, hitting and bouncing off one another. Some of the atoms falling through this void get stuck together…and those atoms are what make up our world and everything in the universe.

Answer 5

b/c our Lord God made them that way.
All this talk about gravity and liquids staying on the same level is Satan's lies.