Stellarium

Look at two screens. 1 year star displacement as 1000 yers: a) http://s020.radikal.ru/i710/1306/61/efd32fb66177.png b) http://s017.radikal.ru/i414/1306/27/419c3792cf07.png

Asked by Igor

Look at two screens.

1 year star displacement as 1000 yers:

1582 year: a) http://s020.radikal.ru/i710/1306/61/efd32fb66177.png

1583 year: b) http://s017.radikal.ru/i414/1306/27/419c3792cf07.png

Great bug, isn't it? Please send me answer on email - why it so

Question information

Language:
English Edit question
Status:
Solved
For:
Stellarium Edit question
Assignee:
No assignee Edit question
Solved by:
gzotti
Solved:
Last query:
Last reply:
Revision history for this message
Best gzotti (georg-zotti) said : 		#1

This is expected behavior.

It is international custom to use the Gregorian Calendar in such programs from the time it was introduced: 1582-Oct-15 as day that followed 1582-10-4. What you see is a displacement of just about those 10 days. Currently ther is no way to set different switching times or force Julian calendar for the present, or force Gregorian for times before 1582.

HTH, G.

Revision history for this message
Igor (coal2001) said : 		#2

Thank you.
It is suspected for those, who rely on calendar, but isn't suspected by those, who rely on tropical year. For example - I want to see summer solstice at 0b.c

May be you will add setting: calendar year/tropical year?

Revision history for this message
Igor (coal2001) said : 		#3

Thanks gzotti, that solved my question.

Revision history for this message
gzotti (georg-zotti) said : 		#4

You can use ecliptical longitude of the sun for this. Summer solstice at l=90°.

Calendar year is a count, more or less independent from the tropics (Julian and Gregorian attempt both to model the tropical year with an integer number of days, with different intercalation schemes to keep the day names in-sync with the seasons). These years do not start with any noteworthy solar longitudes.

On the other hand Tropical year is a duration without count. Not clear what you mean.

Even if somebody implemented a way to use a proleptic Gregorian calendar, the well-known key dates will be off by a few days in the distant past (around JD0 or so).
G.