 Greetings and welcome to the Introduction to Astronomy. In this week's Astronomy of Other Cultures, we are going to start looking at Maya astronomy and introduce that a little bit. So we're looking at the astronomy of the early Americas, or at least parts of that. So let's go ahead and get started and summarize a little bit about what we will look at over the next few lectures. What we learned about the Mayas, who were located near the Yucatan Peninsula in Mexico, is that they gave us a very extremely accurate astronomy, and in fact had very accurate measurements for the month, based on the moon, and the year, based on the motion of Earth around the sun. They had a number of calendars that we can look at, including the Long Count calendar, which of course became very well known in 2012, which was from the believed date of creation. So the initial creation date based on Mayan mythology was the origin of the Long Count calendar. We will also want to look at the codices of the Maya, and the codices are the written records that remain of the Maya observations and almanacs there. Unfortunately, nearly all of these were destroyed by the Spanish, when that area was conquered by the Spanish conquistadors. So then that what we have left is only four of these survive. So we can see a picture of part of one of those here. Again, that is the written records that we have of what the Maya knew. Then we are going to look at the Maya observatories, or at least one main one, what would be El Caracol. That date back over a thousand years, and we will see how Venus was very important for many of the observations, and they had very accurate measurements of the orbit of the planet Venus. Now you may wonder why Venus would be so important, but do remember that Venus is the brightest star-like object in the night sky. So it was very prominent for some of these early civilizations, and again we are seeing how it differs from the western civilization that we are used to looking at, that things were based on Venus here, as opposed to just the sun and the moon in many other western cultures. So let's go ahead and finish up with our summary, and what we are going to look at is, and we are going to see that the Maya civilization had a very well-developed astronomy. Many written records were made, but the vast majority of those were destroyed by the Spanish. And we are going to look at some of the ruins of Maya observatories and pyramids, which still exist today. So that concludes our introduction to Maya astronomy. We'll be back again next week for another astronomy of other cultures. So until then, have a great day, everyone, and I will see you in class.