What is the primary cause of the seasons?
Earth’s north-south axis is tilted 23.5 degrees compared to plane of our orbit which causes the seasons
Where does the sun rise and set?
The sun rises in the east and sets in the west, marking day and night.
What is the latitude of the equator?
0 degrees
What is a lunation?
A lunation is a full cycle of the Moon’s phases, from one New Moon to the next, lasting approximately 29.5 days.
What is the difference between a waxing and waning moon?
Waxing means the Moon is increasing in illumination, while waning means it is decreasing.
What objects (if any) mark the North and South Celestial Poles?
The North Celestial Pole is marked by Polaris. The South Celestial Pole has no bright star to mark it directly.
What is Stonehenge aligned with and explain its significance.
Stonehenge is aligned with the summer solstice sunrise and the rising sun on this day appears directly in front of the heel stone.
What is Newgrange aligned with and explain its significance
Newgrange is aligned with the winter solstice sunrise and is the shortest day of the year, symbolizing rebirth or reincarnation for the dead. After this day, the sun rises progressively earlier, suggesting a new beginning.
Chaco Canyon aligns with both solstices and equinoxes and a sun dagger is presented on the staircase, featuring different petroglyphs in different ways. (look at notes for more detail)
What is the cause of the solar and lunar eclipse and during what moon do they occur?
A solar eclipse occurs when the Moon passes between the Earth and the Sun, blocking the Sun’s light. This happens during a New Moon.
A lunar eclipse occurs when Earth’s shadow falls on the Moon, blocking sunlight. This happens during a Full Moon.
What 2 characteristics of the planet Venus caused the Mayans to identify it as a special kind of star?
Venus has a bright heliacal rise and sets in either the morning or evening, making it distinct from other celestial bodies.
What physical proof do we have that the Maya tracked eclipses and the planet Venus?
The Dresden Codex, a Mayan text, contains precise records of eclipses and Venus’ cycles
Why do we see different stars and constellations at different times of the year?
Earth’s orbit around the Sun causes different sections of the sky to become visible, changing which stars are visible each season.
What was the primary motivation for studying the sky in Ancient Egypt?
The primary motivation was to predict the annual flooding of the Nile, which was crucial for agriculture.
Why are there so many ‘60s’ in our units for time and angle?
The Babylonians used a base-60 numerical system, chosen for its divisibility by multiple numbers, which influenced modern units of time and angle.
Why do we add a leap day every 4 years? Who incorporated this rule into our calendar, and from what civilization did he learn this rule?
Leap days correct the calendar for the extra 0.25 days it takes Earth to orbit the Sun annually.
Julius Caesar incorporated this rule into the Julian calendar after learning it from the Egyptians.
Why do we now use the Gregorian calendar instead of the Julian calendar?
The Julian calendar had a slight miscalculation that caused a drift in the date of equinoxes. Pope Gregory XIII reformed it to better align with the solar year.
Why can we not see our astrological constellation in the month we were born?
The Sun is in front of that constellation during your birth month, so it’s not visible in the night sky at that time.
Why was the star Sirius used to mark the beginning of a new year?
Sirius’s heliacal rising occurred just before the Nile’s flood, making it a reliable marker for the start of the agricultural season.
For each of the 5 visible planets, what aspect of their appearance was used to choose the Babylonian/Greek god to name them for?
Mercury: Named for the messenger god due to its fast movement across the sky.
Venus: Associated with love and beauty, as it’s the brightest and often a morning or evening "star."
Mars: Named for the god of war because of its red color, reminiscent of blood.
Jupiter: Linked to the king of gods due to its large size and brightness, dominating the night sky.
Saturn: Named for the god of agriculture, as it moves slowly, symbolizing patience and time.
What was El Caracol likely used for, and how do we know this?
Likely used for observing Venus. This is supported by its specific alignment to track Venus’ solstice positions and its 584-day cycle.
State the 8 phases of the moon in order of appearance
New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, 3rd/Last Quarter, Waning Crescent.
What 2 features of the Pyramid of Kukulkan (El Castillo) tell us that the Maya had deciphered the solar cycle?
1. 91 steps on each of its four staircases, totalling 365 steps—one for each day of the year.
2. During the equinoxes, the sunlight casts a shadow on the pyramid that creates the illusion of a serpent slithering down the staircase, signifying their understanding of the solar cycle.
Describe the evidence in the Mayan Dresden codex that tells us that the Maya understood the Venus cycle and were able to predict, for eternity, the dates on which the appearances and disappearances of Venus would occur.
The Dresden Codex includes Venus tables recording its 584-day cycle, allowing the Mayans to predict its movements eternally.
What was it about the Mayan number system that facilitated their ability to find patterns in their numeric records of the events in the sky?
The Mayan base-20 numeric system allowed for the recording of large numbers, which enabled them to identify patterns in astronomical events and calculate future celestial occurrences.