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Aristotle added a fifth element, aether (αἰθήρ aither), as the quintessence, reasoning that whereas fire, earth, air, and water were earthly and corruptible, since no changes had been perceived in the heavenly regions, the stars cannot be made out of any of the four elements but must be made of a different, unchangeable, heavenly ...
Although the Sun is a star, its photosphere has a low enough temperature of 6,000 K (5,730 °C; 10,340 °F), and therefore molecules can form. Water has been found on the Sun, and there is evidence of H 2 in white dwarf stellar atmospheres. [2] [4] Cooler stars include absorption band spectra that are
The terrestrial sphere was made of four elements, namely earth, air, fire, and water, subject to change and decay. The celestial spheres were made of a fifth element, an unchangeable aether. Objects made of these elements have natural motions: those of earth and water tend to fall; those of air and fire, to rise.
Following Anaximander, his pupil Anaximenes (c. 585 – c. 528/4) held that the stars, Sun, Moon, and planets are all made of fire. But whilst the stars are fastened on a revolving crystal sphere like nails or studs, the Sun, Moon, and planets, and also the Earth, all just ride on air like leaves because of their breadth. [9]
Therefore, there must be fire at the center of the cosmos. [6] According to Philolaus, the central fire and cosmos are surrounded by an unlimited expanse. Three unlimited elements: time, breath, and void, were drawn in toward the central fire, where the interaction between fire and breath created the elements of earth and water.
Condensation would make the air denser, turning it into wind, clouds, water, earth, and finally stone. Rarefaction would make the air less dense as it eventually becomes fire. Anaximenes also developed a model of the Earth, describing it as a flat disc floating atop the air while the Sun and stars are also flat and float alongside it.
Ch.3 Composition of the four elements; air, earth, fire, and water. Topics also include the composition of the space between earth and stars, the double nature of exhalation, and the composition of clouds. This chapter also contains Anaxagoras' analysis of the element ether Ch.4 Shooting Stars Ch.5 The Aurora Borealis and its affects
Circa 450 BC Empedocles imagined fundamental elements (fire (), earth (), air (), and water ()) and "forces" of attraction and repulsion allowing the elements to interact. Prior to this, Heraclitus had claimed that fire or change was fundamental to our existence, created through the combination of opposite properties. [1]