To those who celebrate, may you receive the gift of wisdom. Blessings at #Epiphany.

Sally Bosken told me all #astronomers had to have a #starofbethlehem speech ready. Thanks to her, I do.

#calendar #timekeeping #seasonoflight #12daysofchristmas #astronomy #histsci
detail from "Mary and Child, surrounded by angels" by "Master of Sant'Apollinare", photograph by N. A. Thune (CC-BY-SA 2.5), courtesy Wikimedia Commons

For those who celebrate, wishing you joy & light throughout the longest night. #wintersolstice blessings

Angle of rays, length of days are the reasons for the seasons
as shown in these #NASAScience solar reflectance maps

maps credit: T. Wong & CERES Science Team, NASA Langley (public domain) via Wikimedia Commons

#SeasonofLight #calendar #timekeeping #astronomy #winter #Sun #solstice #heliophysics

For those who celebrate, Io, Saturnalia!

Running from December 17 to ~23, #Saturnalia celebrated a #Roman Golden Age, when #Saturnus ( #Saturn) ruled & taught his people #argriculture and civilized behavior, by reversing the normal social order.

#SeasonofLight #calendars #timekeeping #Rome #history
photograph by Carole Raddato 2015 CC-BY-SA 2.0 via Flickr

For those who celebrate, chag urim sameach. May your Hanukkah and home be full of light.

Hanukkah begins on 25 Kislev and lasts 8 days. Over a 19-year cycle, the Jewish calendar uses variable-month years and variable-length months to achieve both solar and lunar alignment. This year, Kislev has 30 days, so Chanukah ends on 2 Tevet.

The Gregorian calendar is only aligned with solar cycles. This year, 25 Kislev began at sunset on 14 December and runs until sunset on 22 December.

#SeasonofLight #Hanukkah #Chanukah #calendars #timekeeping #astronomy

For those who celebrate, may #Advent strengthen your heart with patience and joy.

Advent is season of preparation for #Christmas.
Early Christians may have associated Jesus' conception and death with the #VernalEquinox, making the #WinterSolstice His birthday.

#SeasonofLight #calendars #timekeeping #Astronomy