Imagine what would happen if we look at the sky and figure out what time is it, what date is it and what season is going on. Sounds crazy isn't it? Now a day we look at watch for time, at calendar for date. Certainly we don't look at sky for time. But that was not the case for our ancestors. Mayans, Greeks, Egyptians, Romans figured the way to measure time by looking at the sky. It is a blessing for us that they did this for us because now we don't have time to look into sky any more.

For us stars in the sky don't mean anything. But for our ancestor this was the way to keep track of time. Ancestors keep track of various astronomical cycle.