Stellarium

Julian date mismatching standard dates

Asked by Steve

I am having some issue understanding date and julian date relationships in Stelarium.

In Stelarium
If I type in 1950 3 21 4 35 0 for my date then click julian date tab it shows it as
2433362.02431 which is odd.

In Other programs:
If I go to Orbiter 2010 Scenario Editor to change my date to 1950 etc etc like above it shows Julian Date as 2433361.690972

If I go to this website to get my corresponding julian date it says
http://aa.usno.navy.mil/data/docs/JulianDate.php
It says:
The Julian date for CE 1950 March 21 04:35:00.0 UT is
JD 2433361.690972

If I go to "Cartes du Ciel" astronomical software and type in date it also shows the correstponding JD as 2433361.690972

So the question is why is Stelarium different than these other 3 respectable softwares? It looks like Stellarium is leaving off the last number and perhaps this might create some mismatch errors but I dont know for sure.
Can someone clarify why other programs are consistant when converting dates to julian dates while Stelarium is different?
thanks

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Steve
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Revision history for this message
Alexander Wolf (alexwolf) said : 		#1

This is so incredibly difficult to specify the version of the program?

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Alexander Wolf (alexwolf) said : 		#2

And yes, this issue has been fixed 5 versions ago.

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Steve (suecke) said : 		#3

Sorry Iam using version 0.14.2 on windows 7 which is the latest. Maybe bug accidently got put back in?

Try typing in dates and comparing results. This website is a quick way to double check and compare.
http://aa.usno.navy.mil/data/docs/JulianDate.php

Revision history for this message
Steve (suecke) said : 		#4

looks like stellarium uses only 5 digits after decimal. Maybe there is a cumulative rounding off effect going on? just guessing.

Revision history for this message
Steve (suecke) said : 		#5

If now your using "correct" CJD instead of chronological JD maybe the tabs should maybe be specific and say something like CJD and MCJD so as not to be confusing or display both. I dont know. My head is spinning trying to get a handle on this

Revision history for this message
Alexander Wolf (alexwolf) said : 		#6

1) I re-check JD in SkyChart and Stellarium for same date and time - both planetariums say the same JD.
2) Your URL is not working in my country
3) What about time zone settings in your computer - it is correct?
4) JD in Stellarium is JD now, not CJD

Revision history for this message
Alexander Wolf (alexwolf) said : 		#7

Wait! Why you compare JD for date and time in UTC and same date and time in your local time zone? Are you have an UTC+0 time zone?

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Steve (suecke) said : 		#8

oh man i finally got it. Your comments clues helped. thank you. I needed to change my computers time zone to greenwhich which is utc+00:00 not utc-8:00 My observation point needed to be on the greenwhich meridian but it was set for pacific time zon which is in california where i live. So now numbers match. thanks

Revision history for this message
Steve (suecke) said : 		#9

i think i assumed if I hit f6 and i changed the "location" red arrow to point to the center of the earth that the time zone would be set for the program

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MR HSNNN (lastreaction) said : 		#10

I think You need to change your time zones. If you are using pacific time zone you need to switch to greenwitch. You can read more at https://my-dating-list.com/