Humans see and feel the days get longer and shorter.. The longest and shortest light or shadow is at a specific point each year. This is the Winter and Summer Solstices and these points were marked in varies ways. Especially in the Stone Age humans realized there was a connection between what happened in space and what happened in their lives. Stonehenge was built in England about 4,000 BCE. in the stone age. Its rocks mark solar and lunar movements. This Spring Equinox became zero Aries in the 360 degree zodiac that the Babylonians developed. This zodiac created and organization for tracking the Sun - tracking the seasons. - and everything in the sky.
Moon phases were obvious. Venus was bright enough that Venus phases and patterns were also tracked.
By 3114 BC an 18.7-year cycle in the rising and setting of the Moon had been discovered. This cycle predicted what was once the eclipses of the Sun and Moon. Those unexpected events had once been terrifying but could now be anticipated. This is now known as a Saros cycle and the image below is from NASA website. It still predicts eclipses.
From a NASA webpage.
In Babylonia, Astronomia was the occupation of some of the temple priests. They kept the records and presented what they knew. The priests were primarily concerned with what was happening in the state as a whole and in the life of the king as the central figure of the state. The Babylonian method of interpretation was based on what took place in the past when the same celestial phenomena were present.
Humans are a story telling species. Stories can organize, explain, and help us remember details and information. Today we call stories from long ago myths. The ancients created myths about the stars and planets. They also used the characteristics of the gods associated with the different planets and the stories linked to the different constellations to develop stories that held messages about their meaning.
What caused them to link specific planets with specific Gods?
What could be seen from the planets, stars and moon?
The brightness and color of light, the orbits, patterns and interactions.
Visible Orbit characteristics include:
Time to Orbit the Sun. (Earth = one year and Saturn=30 years)
Shape of orbit (called Eccentric. Circle=0 and less than 1=eclipse (similar to oval)
Inclination of Orbit to the path of the Sun which is called the ecliptic. The name "ecliptic" comes from the fact that eclipses take place along this line. Most major planets in our solar system stay within 3 degrees of the ecliptic. Mercury is the exception; its orbit is inclined to the ecliptic by 7 degrees.
Patterns included appearance, disappearance and stations of planets.
By 2000 BCE even the pentagram of Venus. was known. Every 8 years there are about 5 inferior conjunctions of Venus. Our Earth orbits eight times for every 13 orbits of Venus and Venus forms a five pedaled flower in this process. Some say this indicates a harmonizing field around our body to support and balance us.
Illustration of closeness (Perihelion and Perigee) and distance (Aphelion and Apogee).
We say that planets orbit stars, but that’s not the whole truth. Planets and stars actually orbit around their common center of mass. This common center of mass is called the barycenter. The barycenter between Earth and the sun is very close to the center of the sun. Jupiter has 318 times more mass than Earth. As a result, the barycenter of Jupiter and the sun isn’t in the center of the sun. It’s
Tilt: The axial tilt is defined as the angle between the direction of the positive pole and the normal to the orbital plane. The angles for Earth, Uranus and Venus are approximately 23°, 97°, and 177° respectively.
Solar Storms, Solar Wind and Magnetospheres are even more important once we leave Earth's protective magnetosphere.