Alexander the Great
Posted: Fri Mar 05, 2021 9:14 am
I've been somewhat preoccupied recently taking a fresh look at when Alexander the Great was born. I can't say I've worked it out to my full satisfaction, but I thought I'd record what I have so far. Conventional history recognizes that there is uncertainty about the exact day he was born, usually stating that it was July 20 or 21, 356 BC, in Pella, Macedonia (today in Greece).
However, there is no doubt of the day Alexander was born. We know it exactly. The problem is that we only know it in the Attic calendar, one of many simultaneous calendars in use in Greece at the time, and we don't know exactly how the calendar fell. In fact, different communities could have slightly different starting dates for each month, even when the theory of the calendar was identical in all of them (which wasn't always the case). It was a mess!
Alexander was born in Pella. For some reason, the town (which still exists) isn't in Solar Fire. I've separately found it's central coordinates as 40°45′42″ N, 22°31′34″ E (203 feet above sea level: above the same elevation as Century City, where I work, wedged between the slightly lower Santa Monica and the slightly higher West Hollywood). Wikipedia lists 40.754669 N, 22.521050 E, which converts to 40N45'17'', 22E31'16''. I'll use the first set of figures in this paragraph, but they're all the same to within a minute of arc.
He was born on the 6th of Hekatombaion - of this, there seems universal agreement. The question is: When was 6 Hekatombaion?
Hekatombaion is the first month of the Attic calendar, primarily an Athenian calendar, and I don't know that it was used in Macedonia, but it's the calendar in which his birth was recorded. Each month began with the neomenia, the first appearance of the New Moon. In theory, this could be different for different cities, but usually there is no question.
While there were considerable inconsistencies in how these were calculated, I believe this particular date was more attentively measured than other Attic dates. First, it was the first month of the year, deserving for that reason alone to be more carefully measured. Second, the date was given to record the birth of the King of Macedonia, and for this even greater care was warranted.
WHAT I KNOW ABOUT DETERMINING THIS DATE: Hekatombaion began with the first appearance of the new Moon at sunset. Most officially, this was its first appearance in Athens, though probably the first appearance was the same across the region. I emphasized above the altitude of Pella: Pictures I've seen show little or no topography or other visual interruptions of the horizon, so there, also, the first appearance wasn't likely to be delayed. The Greek day ran from sunrise to sunrise.
WHAT I DON'T KNOW ABOUT THIS: One source claims that the month officially began the day (morning) after the first Moon sighting. Most sources I can find say nothing about this at all. It makes sense, in that the prior morning the new Moon wouldn't yet have been seen, so (even though it would be seen at the end of the day) it would be hard to call it a new month. Nonetheless, I just don't know for sure which day started the month, giving a one-day confusion from the start.
TIMING THE NEOMENIA: A New Moon occurred July 14, 356 BC, shortly before sunset, with Sun and Moon 5-6° above Descendant. Moon clearly wouldn't be visible that day. The next day, July 15, Sun's last rays dropped below the horizon at 7:31 PM with Moon 7° above horizon. This, also, is too little. It seems, therefore, that the first visibility of the New Moon was July 16, when, at sunset, Moon was 14°25' above the horizon, surely visible on a clear day (and Athens' leaders seemed to have sophisticated enough astronomy not to let clouds thrown them off). I doubt the visibility in Pella mattered but, just to put it on record, at sunset Moon was 13°19' above the western horizon as the sun's last rays vanished below the horizon.
If the next morning, then, was 1 Hekatombaion, then 6 Hekatombaion was July 22 - not July 20 or 21 as usually stated. Of course, if my one source is wrong and the month began the day that the new Moon would later appear at sunset, then we're back to July 21 for the 6th of the month. BTW, I think the occasional mention of July 20 as a birth date comes from someone mistaking "the new Moon" as the date of the astronomical conjunction July 14; but that wasn't how it was calculated.
I think Alexander was born July 22, 356 BC.
However, there is no doubt of the day Alexander was born. We know it exactly. The problem is that we only know it in the Attic calendar, one of many simultaneous calendars in use in Greece at the time, and we don't know exactly how the calendar fell. In fact, different communities could have slightly different starting dates for each month, even when the theory of the calendar was identical in all of them (which wasn't always the case). It was a mess!
Alexander was born in Pella. For some reason, the town (which still exists) isn't in Solar Fire. I've separately found it's central coordinates as 40°45′42″ N, 22°31′34″ E (203 feet above sea level: above the same elevation as Century City, where I work, wedged between the slightly lower Santa Monica and the slightly higher West Hollywood). Wikipedia lists 40.754669 N, 22.521050 E, which converts to 40N45'17'', 22E31'16''. I'll use the first set of figures in this paragraph, but they're all the same to within a minute of arc.
He was born on the 6th of Hekatombaion - of this, there seems universal agreement. The question is: When was 6 Hekatombaion?
Hekatombaion is the first month of the Attic calendar, primarily an Athenian calendar, and I don't know that it was used in Macedonia, but it's the calendar in which his birth was recorded. Each month began with the neomenia, the first appearance of the New Moon. In theory, this could be different for different cities, but usually there is no question.
While there were considerable inconsistencies in how these were calculated, I believe this particular date was more attentively measured than other Attic dates. First, it was the first month of the year, deserving for that reason alone to be more carefully measured. Second, the date was given to record the birth of the King of Macedonia, and for this even greater care was warranted.
WHAT I KNOW ABOUT DETERMINING THIS DATE: Hekatombaion began with the first appearance of the new Moon at sunset. Most officially, this was its first appearance in Athens, though probably the first appearance was the same across the region. I emphasized above the altitude of Pella: Pictures I've seen show little or no topography or other visual interruptions of the horizon, so there, also, the first appearance wasn't likely to be delayed. The Greek day ran from sunrise to sunrise.
WHAT I DON'T KNOW ABOUT THIS: One source claims that the month officially began the day (morning) after the first Moon sighting. Most sources I can find say nothing about this at all. It makes sense, in that the prior morning the new Moon wouldn't yet have been seen, so (even though it would be seen at the end of the day) it would be hard to call it a new month. Nonetheless, I just don't know for sure which day started the month, giving a one-day confusion from the start.
TIMING THE NEOMENIA: A New Moon occurred July 14, 356 BC, shortly before sunset, with Sun and Moon 5-6° above Descendant. Moon clearly wouldn't be visible that day. The next day, July 15, Sun's last rays dropped below the horizon at 7:31 PM with Moon 7° above horizon. This, also, is too little. It seems, therefore, that the first visibility of the New Moon was July 16, when, at sunset, Moon was 14°25' above the horizon, surely visible on a clear day (and Athens' leaders seemed to have sophisticated enough astronomy not to let clouds thrown them off). I doubt the visibility in Pella mattered but, just to put it on record, at sunset Moon was 13°19' above the western horizon as the sun's last rays vanished below the horizon.
If the next morning, then, was 1 Hekatombaion, then 6 Hekatombaion was July 22 - not July 20 or 21 as usually stated. Of course, if my one source is wrong and the month began the day that the new Moon would later appear at sunset, then we're back to July 21 for the 6th of the month. BTW, I think the occasional mention of July 20 as a birth date comes from someone mistaking "the new Moon" as the date of the astronomical conjunction July 14; but that wasn't how it was calculated.
I think Alexander was born July 22, 356 BC.