The Mayans and Egyptians Lauren Kendrick

WWK About ancient Egyptian and Mayan civilizations and their astronomical practices.

Mayans

Beastly Mathematicians The Mayan used a base number of 20 and a line and dot system as visual representation. Larger numbers where written in powers of 20 In example for us, with 10 as our base number 32 can be written 3*10+2 Mayan system would be 1*20+12 because of their base number of 20 Numbers were also written top to bottom. Addition and subtraction were easy because of this system however they did not use fractions.

The Mayan The calendar that developed in Mesoamerica had 260 days. This calendar gave each day a name and numbered the days However there are 20 Mayan day names so after the 13 th day the next day was numbered 1 again. This calendar was used probably before the beginning of writing.

Years and months The Mayans also tracked a solar year which had 365 days in a year. Because they couldn’t use fractions the ¼ day left over from their normal calendar caused it to drift with regard to the actual solar year. The 365 day year contained months numbered and were also named. The Maya also added a five-day month called Wayeb composed of 5 days which were considered unnamed and unlucky

Egyptians

Genisis Their main god, Amon-Ra, was said to hold the power of the sun. However the original Egyptian calendar was lunar not solar. The lunar calendar didn’t always fit with the seasons so extra months were sometimes added by watching for the Heliacal rising of Sirius. The heliacal rising of Sirius also marked the time when the Nile river would flood and irrigate the farmland that the Egyptian society depended on. Ummm…. WHAT??? The heliacal rising of a star (or other body such as the moon, a planet or a constellation) occurs when it first becomes visible above the eastern horizon for a brief moment just before sunrise,

Timeee Egyptians did end up switching to a solar calendar. Months had 30 days with three 10 day weeks, beginning of the week marked by Decans, wich were the groups of stars also used in a method of time keeping called a star clock. A star clock has the name of each decan that rose on a certain date and time. Understanding this method you could decans rising and use the star clock to find time.

My favorite fact Once a decan is no longer visible in the night sky, it does not rise heliacally again for seventy days. The Egyptians believed that during this time, the decan had died and was being purified in the Duat, or the underworld. After seventy days in the Duat, the decan was reborn. Apparently in correlation with that, Egyptian embalmers took seventy days to prepare a body for burial

Wait what about the pyramids!? Pyramids were build using astronomy and geography.The four corners of most pyramids line up almost exactly with the four cardinal directions, only deviating by about six hundredths of a percent. It also seems that many pyramids are oriented to the three stars that make up Orion's belt. A theory known as the Star Correlation Theory points out that the "air shafts" are perfectly aligned to point to those stars, and to the star Sirius. However because the world and universe keep moving Orion’s belt has shifted slightly since their time.