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A Most Unusual Julian Date Approaching

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BRJ's picture
A Most Unusual Julian Date Approaching

For those of us who enjoy unusual numerical situations and astronomical trivia, I note (and have been anticipating for a while now) the approaching occurrence of a once in a lifetime Julian date now just days away. On this weekend over the course of moving from the night of Saturday, May 10th, into Sunday, May 11th, observers around the globe will have the potential for contributing observations with a Julian date of 2,456,789. While certainly of no scientific consequence whatever, it is a truly unique numerical situation for those of us who use this traditional dating system in our VS observing and the last such that will ever include the final six numbers of a Julian date being all positive and coming in numerical sequence.

As perhaps a bit of AAVSO-associated trivia in this area, I recall my old friend and mentor Edward Oravec (OV) long ago telling me about a small tight knit group of older AAVSOers members who would celebrate the 10,000 day change in the Julian calendar's date (like 2,440,000 and 2,450,000) as marking the turning of a calendar page in the AAVSO's history, since all observers strictly empoyed the Julian system to report observations to HQ in those days. This was, of course, an occasion most of them got to personally acknowledge only once or twice in the course of their observing careers. Ed indicated that this group of old friends would try to gather on the nearest convenient day to the date's change-over and raise a glass of wine, or other spirits, to mark the occasion. Sounds to me like next Sunday would be an equally fitting occasion to do the same, at least individually.

J.Bortle   (BRJ)

roe's picture
Unusual Julian Date

I'll drink to that!

J. Roe [ROE]

Gustav Holmberg
I'll drink to

I'll drink to that!

/Gustav, HGUA

weo's picture
Upcoming special JD

Thanks for alerting us, John! If it's clear here, I'll be out at 4:17:42 am EDT on Sunday making an observation  (JD 2456789.0123)  :)

Clear skies,

Elizabeth Waagen

BRJ's picture
Unusual Julian Date

Adding a further bit to this thread I would note that the last similar sequential run of the final six numbers in the Julian Calendar (2,345,678) seems to have occurred in 1710 and next one, having a "0" following the 9, will be 2,567,890 in the year 2318.

In spite of the nearly full moon this evening, I did get in 15 estimates, several being CVs found in outburst, and I gave a little toast to the date.

J.Bortle   (BRJ)


WGR's picture
Unusual JD

Hello John

Thanks for pointing this out.  I entered 6789 as the last 4 digits of my file name last night.  I did not notice the 245 that preceeds it.  I got SBS 1108+574.  Will reduce the data shortly.


AAX's picture
Hi friends, In 2009 I lead a

Hi friends,
In 2009 I lead a campaign here in Brazil regarding JD 2455000, as we can read at this link:

Well, only me sent reports. I tried to observe some variable stars with Avelino Alves (AAA) but sky was cloudy on that night of June 17, 2009.

hambsch's picture
Special date from last night



I got a near perfect JD last night remotely amongst my observations:

Z CHA,2456789.56781,15.434, 0.036,CV,NO,STD,000-BJZ-517,17.412,000-BJZ-519,18.392,2.11,na,12447AKW,Standard mag: C = 13.128  K = 14.179




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