Category Archives: earth

Evolution of Kinship Societies into Tributary Societies: An Important Step in Development of Cities

The first cities emerged as a result of a fundamental reorganization of food production and economic diversification in human societies. Before the advent of cities, ancient peoples lived in clan groups and villages organized around extended kin, or family, relationships … Continue reading

Posted in Class Notes, earth, society, urban morphology, Urban Studies | Leave a comment

Hailstones in Our Lawn

Hail is a form of precipitation that falls from the sky as pellets of ice. The pellets can range in size from small pea-sized pellets to hailstones as large as grapefruits (more on hail size below). The formation of hail … Continue reading

Posted in earth | Leave a comment

Obliquity, inclination and eccentricity of Earth – a model: Part 2

Originally posted on Tallbloke's Talkshop:
Kepler’s trigon – the orientation of consecutive Jupiter-Saturn synodic periods, showing the repeating triangular shape (trigon). This of course follows on from the very recent Part 1 of the model. Since Jupiter and Saturn…

Posted in earth | Leave a comment

Obliquity, inclination and eccentricity of Earth – a model: Part 1

Originally posted on Tallbloke's Talkshop:
Earth’s Axial Tilt, or Obliquity [Credit: Wikipedia] First let’s get the approximate target numbers for the model. ‘The inclination of Earth’s orbit varies with respect to the solar system’s invariant plane with a period…

Posted in earth | Leave a comment