Sunday December 21, 1023
A date scroll with Latin text from “The Extremes of Good and Evil” by Cicero, written in 45 BC.

December 21, 1023: Day of the Week

December 21, 1023 was the 355th day of the year 1023 in the Gregorian calendar. There were 10 days remaining until the end of the year. The day of the week was Sunday.

The day of the week for December 21, 1023 under the old Julian calendar was Saturday. Did you notice the difference with the Gregorian calendar?

If you are trying to learn French then this day of the week in French is dimanche.

A person born on this day will be 1,000 years old today. If that same person saved a dollar every day starting at age 3, then by now that person has accumulated $364,422.00 today.

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Here’s the December 1023 Gregorian calendar. You can also browse the full year monthly 1023 calendar.

December 1023
SunMonTueWedThuFriSat
 123456
78910111213
14151617181920
21222324252627
28293031   

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Zodiac & Birthstone

Sagittarius is the zodiac sign of a person born on this day. Turquoise is the modern birthstone for this month. Onyx is the mystical birthstone from Tibetan origin that dates back over a thousand years.

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December 21, 1023 by the Numbers

  • 365,518 days since December 21, 1023
  • 1,000 years, 9 months, and 0 day ago
  • 12,009 months since then
  • December 21 is in the 51st week of the year 1023 (ISO 8601)
  • 52,216 weeks ago
  • The year 1023 is not a leap year

Gregorian versus the old Julian calendar

A note to students, teachers, scholars and anyone else passionate about this topic. As stated in the front page, this website is using the Gregorian calendar as the basis for all “day of the week” computation whether or not the Gregorian calendar is relevant for the date in question (December 21, 1023). Educators should point out the primary reason why Pope Gregory XIII introduced a new calendar system in October 1582. That is, to make the computation for the annual date of Easter more accurate since it is the foundation of the Christian faith.

Even with that purpose in mind, the Gregorian calendar too will become out of sync. It has a known approximation error of about one day for every 7,700 years assuming a constant time interval between vernal equinoxes (which is not true). This is better compared to the one day for every 128 years error of the Julian calendar.

Share InfoNow try another date like anniversaries, birthdays of someone you know or any other date that is special to you. Don’t forget to share the info to your friends, loved ones or social media followers. Who knows, they might appreciate and thank you for it.