Wiccan views of divinity the ancient Greek conception, where the elements correspond to matter (earth) and energy (fire), with the mediating elements (water, air) relating to the phases of matter (fire/earth mixtures). A more modern conception correlates the four elements to the four states of matter known to science: Solid (earth); Liquid (water); Gas (air); and Plasma (fire); with the akasha element corresponding to pure Energy. The Aristotelian system proposes a fifth or quintessential element, spirit (aether, akasha). The preferred version is a matter of ongoing dispute in the Wiccan community. There are other non-scientific conceptions, but they are not widely used among Wiccans.
Formation and evolution of the Solar System of 4.6 billion years, suggesting that the Solar System must be at least this old. Studies of discs around other stars have also done much to establish a time frame for Solar System formation. Stars between one and three million years old have discs rich in gas, whereas discs around stars more than 10 million years old have little to no gas, suggesting that giant planets within them have ceased forming. Note: All dates and times in this chronology are approximate and should be taken as an order of magnitude indicator only. Formation and evolution of the Solar System The