# How Far Back Can We Actually Document Some Event, to the day? **URL:** \ **Category:** Factual Questions\ **Created:** [June 21, 2007, 6:34am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817 "2007-06-21T06:34:35Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\ **Post date:** [June 21, 2007, 6:34am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/1 "2007-06-21T06:34:35Z")
What’s the date of the oldest known event? That is, what’s the oldest event that where we know (or can estimate) the exact date it occurred? I’m guessing it’s an eclipse. [Apparently the earliest solar eclipse happened on 5 March 1223 BC](http://www.nature.com/nature/journal/v338/n6212/abs/338238a0.html). A clay tablet unearthed in 1948 in modern-day Syria mentioned this event. But maybe an older date can be pinpointed. Anybody? (Thread inspired by [How far back can we actually document someone?](http://boards.straightdope.com/sdmb/showthread.php?t=425420)). ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [June 21, 2007, 7:22am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/2 "2007-06-21T07:22:38Z")
The Supernova that created the Crab Nebula was viewed on earth in 1054 BC, and recorded by the Chinese and others. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [June 21, 2007, 7:36am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/3 "2007-06-21T07:36:02Z")
Oops. I meant 1054 AD. Not BC. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [June 21, 2007, 7:52am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/4 "2007-06-21T07:52:16Z")
> [@MfM](#): > > Apparently the earliest [recorded] solar eclipse happened on 5 March 1223 BC. I’m guessing that that’s as good as you’re going to get. There are other astronomical references in cuneiform tablets to earlier events, such as the lunar observations on the Venus Tablet of Ammisaduqa, but so far nobody has fixed them unambiguously. That is, they might refer to any one of a number of occurrences of the same type of astronomical event, separated by decades or centuries. ---
**Author:** ![Alive\_At\_Both\_Ends](https://avatars.discourse-cdn.com/v4/letter/a/73ab20/32.png) [@Alive\_At\_Both\_Ends](https://boards.straightdope.com/u/Alive_At_Both_Ends)\ **Post date:** [June 21, 2007, 9:11am UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/5 "2007-06-21T09:11:50Z")
Other than the mere fact of an eclipse, the earliest event whose date is precisely known was a battle between the Lydians and the Medians, in Asia Minor - May 28, 585 BC. But this date is only known because the battle was interrupted by an eclipse, so perhaps it doesn’t count. ---
**Author:** ![muttrox](https://avatars.discourse-cdn.com/v4/letter/m/a8b319/32.png) [@muttrox](https://boards.straightdope.com/u/muttrox)\ **Post date:** [June 21, 2007, 1:18pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/6 "2007-06-21T13:18:32Z")
You didn’t say the event has to involve humans or be recorded in any way. I imagine we can trace back various astronomical events a few million years or so. ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [June 21, 2007, 1:25pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/7 "2007-06-21T13:25:48Z")
Outside eclipses, did the ancients record events that accurately? ---
**Author:** ![Trunk](https://avatars.discourse-cdn.com/v4/letter/t/87869e/32.png) [@Trunk](https://boards.straightdope.com/u/Trunk)\ **Post date:** [June 21, 2007, 1:32pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/8 "2007-06-21T13:32:40Z")
[QUOTE=muttrox] You didn’t say the event has to involve humans or be recorded in any way. I imagine we can trace back various astronomical events a few million years or so. [/QUOTE] to the day? eta: oh, like an eclispe or something. Never mind. original post left for posterity. ---
**Author:** ![Alive\_At\_Both\_Ends](https://avatars.discourse-cdn.com/v4/letter/a/73ab20/32.png) [@Alive\_At\_Both\_Ends](https://boards.straightdope.com/u/Alive_At_Both_Ends)\ **Post date:** [June 21, 2007, 2:56pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/9 "2007-06-21T14:56:37Z")
[QUOTE=Quartz] Outside eclipses, did the ancients record events that accurately? [/QUOTE] Julius Caesar was killed on the Ides of March - 15 March 44 BC. That’s fairly ancient. It wouldn’t surprise me to find precise dates for non-astronomical events even further back. ---
**Author:** ![CJJ](https://avatars.discourse-cdn.com/v4/letter/c/ecc23a/32.png) [@CJJ](https://boards.straightdope.com/u/CJJ)\ **Post date:** [June 21, 2007, 3:12pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/10 "2007-06-21T15:12:24Z")
The book _The Timetables of History_ claims the “First exactly-dated year in human history” was 4241 BCE, the year the solar calendar was first adopted in Egypt. It’s not an exact day, and I think the translation to the Gregorian calendar is based on comparative astronomical observations, but still… ---
**Author:** ![Commodore\_Penguin](https://avatars.discourse-cdn.com/v4/letter/c/eada6e/32.png) [@Commodore\_Penguin](https://boards.straightdope.com/u/Commodore_Penguin)\ **Post date:** [June 21, 2007, 5:13pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/11 "2007-06-21T17:13:48Z")
How far back? The beginning, actually. October 23, 4004 BCE. This was on a Sunday. Well, more specifically the evening before. And I’d say Man came about at around 9 o’clock in the morning. If you follow the [Ussher-Lightfoot Calendar](http://en.wikipedia.org/wiki/Ussher-Lightfoot_Calendar). ---
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [June 21, 2007, 5:53pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/12 "2007-06-21T17:53:43Z")
As far as actual events here on Earth, rather than eclipses and such, a candidate for “earliest possible human event that can be dated to the day” is the [Battle of Halys](http://en.wikipedia.org/wiki/Battle_of_Halys), May 28, 585 B.C.E., between the Medes and the Lydians in what is now Turkey. Of course, the reason the Battle of Halys can be dated to the day is that traditionally the two sides called off the fighting when a total eclipse of the Sun occured (which they took as an omen); and we can date exactly when a total eclipse visible from that location would have taken place. So I guess it’s eclipses all the way down. ---
**Author:** ![wasson](https://avatars.discourse-cdn.com/v4/letter/w/4da419/32.png) [@wasson](https://boards.straightdope.com/u/wasson)\ **Post date:** [June 21, 2007, 6:19pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/13 "2007-06-21T18:19:35Z")
[QUOTE=MEBuckner] As far as actual events here on Earth, rather than eclipses and such, a candidate for “earliest possible human event that can be dated to the day” is the [Battle of Halys](http://en.wikipedia.org/wiki/Battle_of_Halys), May 28, 585 B.C.E., between the Medes and the Lydians in what is now Turkey. Of course, the reason the Battle of Halys can be dated to the day is that traditionally the two sides called off the fighting when a total eclipse of the Sun occured (which they took as an omen); and we can date exactly when a total eclipse visible from that location would have taken place. So I guess it’s eclipses all the way down. [/QUOTE] This seems very familiar, like perhaps I read it in this very thread, like maybe 7 posts ago or so. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [June 21, 2007, 6:33pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/14 "2007-06-21T18:33:16Z")
But still nobody has been able to pinpoint the exact date that the -gry problem first reared its head on teh Web. ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [June 21, 2007, 6:34pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/15 "2007-06-21T18:34:28Z")
[QUOTE=wasson] This seems very familiar, like perhaps I read it in this very thread, like maybe 7 posts ago or so. [/QUOTE] Hmm. Tough crowd around here… ---
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [June 21, 2007, 6:51pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/16 "2007-06-21T18:51:09Z")
[QUOTE=wasson] This seems very familiar, like perhaps I read it in this very thread, like maybe 7 posts ago or so. [/QUOTE] :smack: Right. Never mind. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [June 21, 2007, 7:52pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/17 "2007-06-21T19:52:43Z")
[QUOTE=wasson] This seems very familiar, like perhaps I read it in this very thread, like maybe 7 posts ago or so. [/QUOTE] Yeah, but I said it in [an earlier thread.](http://boards.straightdope.com/sdmb/showthread.php?p=8226704) I win. 😛 ---
**Author:** ![Billdo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/billdo/32/315_2.png) [@Billdo](https://boards.straightdope.com/u/Billdo)\ **Post date:** [June 21, 2007, 10:09pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/18 "2007-06-21T22:09:53Z")
[QUOTE=Commodore Penguin] October 23, 4004 BCE. This was on a Sunday. Well, more specifically the evening before. And I’d say Man came about at around 9 o’clock in the morning. [/QUOTE] I really appreciate your using “BCE” terminology so as to avoid offending those people who subscribe to Bishop Ussher’s chronology but not to Christian theology. 😉 ---
**Author:** ![bonzer](https://avatars.discourse-cdn.com/v4/letter/b/45deac/32.png) [@bonzer](https://boards.straightdope.com/u/bonzer)\ **Post date:** [June 21, 2007, 11:10pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/19 "2007-06-21T23:10:57Z")
[QUOTE=Alive At Both Ends] Julius Caesar was killed on the Ides of March - 15 March 44 BC. That’s fairly ancient. [/QUOTE] Oddly, there’s a complication to this case that probably strictly rules it out as even a candidate for dating something to the exact day. When Caesar introduced what we now call the Julian Calendar there was [a big screwup in the implementation](http://www.wilkiecollins.demon.co.uk/roman/calhis.htm). This wasn’t noticed until Augustus was emperor, forcing him to introduce a further set of reforms. Due to the patchiness of the surviving records, there’s apparently a degree of uncertainty about exactly what happened during this stage, with the result that dates in the Roman calendar prior to about 8 BCE can’t be pinned down to better than a few days. (Which is why, for instance, [this converter](http://www.csgnetwork.com/julianmanycalconv.html) has a disclaimer about such earlier dates.) We thus can’t say on exactly which [Julian Date](http://en.wikipedia.org/wiki/Julian_day) the Romans started 44 BCE and hence can’t exactly pin down the Ides of March that year. We thus have an exact contemporary record of the date in the Roman calendar, but can’t quite exactly match it to an absolute date. (I didn’t realise this nuance until poking about as part of an old thread asking on which day of the week Caesar was killed. That thread seems to have gone to the Great Hamster Playground in the Sky.) ---
**Author:** ![Commodore\_Penguin](https://avatars.discourse-cdn.com/v4/letter/c/eada6e/32.png) [@Commodore\_Penguin](https://boards.straightdope.com/u/Commodore_Penguin)\ **Post date:** [June 21, 2007, 11:29pm UTC](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817/20 "2007-06-21T23:29:51Z")
[QUOTE=Billdo] I really appreciate your using “BCE” terminology so as to avoid offending those people who subscribe to Bishop Ussher’s chronology but not to Christian theology. 😉 [/QUOTE] It’s a real niche demographic, sure, but one we should not disenfranchise. [Next page](https://boards.straightdope.com/t/how-far-back-can-we-actually-document-some-event-to-the-day/408817.md?page=2)