# https://www.youtube.com/watch?v=M9vGCAElBu0 # STB스페셜71회ㅣ 박석재 박사의 개천기 1부 Holidays in South Korea: 1/1, 3/3, 5/5, 7/7, 9/9 New year Third day of third lunar month Tano Gyeonwoo-jiknyeo Thanksgiving # ====================================================================== Phases of moon: DOC in northern areas waxing crescent moon (D shape) -> full moon (O shape) -> waning moon (C shape) In southern areas (Australia, Africa), it's COD order # ====================================================================== Locations of each moon when sun disappears and appears 1. new moon (in initial couple of days of month in lunar calendar) 2. waxing crescent moon 3. full moon 4. waning moon 5. old moon (in last couple of days of month in lunar calendar) # ====================================================================== New moon: When sun is in the sky, moon is not bright because sun makes sky bright When sun starts to set, sky becomes dark In initial couple of days (generally 2-4th day) of month in lunar calendar, moon is located near to sun So, moon takes sunlight partially, and moon looks new moon shape For visualization, 1. Imagine you're standing on the earth. 2. Imagine sun is located in far below from you So, sky is dark (that is, night time) 3. Moon orbits around earth. Imagine moon is shown from place where you're standing. Also imagine moon is in lower altitude, and that means moon is located in near to sun. But note that sun is located in far distance from both earth and moon. 4. Light of sun lays onto moon partially (with making new moon shape) from far below distance. 5. On the other hand, waxing crescent moon and full moon is located in higher altitude than new moon, so, much of light of sun can lay onto them. # ====================================================================== When sun starts to set at 18:00, waxing crescent moon is located in highest southern area Sun light lays down onto moon from side and far direction of the sun So, waxing crescent moon brights in half Waxing crescent moon starts to rise at 12:00 when sun is in highest southern area but waxing crescent moon is not bright at 12:00 because sky is too bright due to existing sun Waxing crescent moon starts to show at 18:00 when sun starts to set Waxing crescent moon sets at 00:00 So, when army builds strategy where army wants to have moon light when they move, and army doesn't want to have moon light when they start to attack, army needs to choose period when waxing crescent moon shows. Specifically, 7 or 8th day as lunar calendar # ====================================================================== Note that, new moon can't show in highest southern area in the sky as if waxing crescent moon is located at 18:00. Since new moon is located in near to to sun, when sun disappears, new moon also disappears after showing in short time at early evening and night So, specifically, you can't see new moon after 22:00 If you read novel where 2 samurais duel at 00:00 with having new moon in the sky, it doesn't actually make sense because new moon can't show after 22:00 # ====================================================================== Full moon When sun sets, moon is located in opposite position to sun So, full moon starts to show when sun starts to set Then full moon shows high in the night Full moon sets when sun rises in the morning So, if you need to move in the night with moon light, you need to choose period when full moon shows # ====================================================================== Waning moon Waning moon rises and starts to show at 00:00 When sun rises at 6:00, waning moon is located in highest southern area (but waning moon is not bright moon due to sun) At 12:00, not bright waning moon sets # ====================================================================== Old moon In old moon peirod, there is no moon in the night sky. When sun starts to show at 6:00, old moon shows for short time, and soon, it becomes not bright moon in the sky