Stellarium / stellarium-web-engine

JavaScript planetarium engine
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wrong time offset in stellarium-web #190

Open claudemartin opened 1 year ago

claudemartin commented 1 year ago

When I change the location on the web version it doesn't affect the time. I.e. it seems that it will still use the local time (offset). When I change the location on the app version to a manual location it will display a time offset (e.g. -7) and also apply it so that the time is local time of that place, not where I am.

Example:

Expected behaviour: Setting the same location (Los Angeles, USA), date/time (e.g. 01:00), and direction (East) should show the same sky. However, it might be daytime when using the same point in time but a different timezone and because of the different position I wouldn't expect Jupiter to be at the same relative direction.

Actual behaviour: I have to set the time to 10:00 to see the same night sky, when Jupiter is also East for some reason.

But I was there and Jupiter was East here in Switzerland, so this is just confusing. I also tried Tokyo. I find it hard to believe that 17:00 is the middle of the night in Japan. Obviously, that is my local time. But then on the App it is nighttime in Japan when I set the time to something like 01:00 and Jupiter is at the same position (East). But they are in a different time zone, so wouldn't Jupiter be at a completely different position? I can't tell which one is wrong or if both the web and the app are wrong or I just don't get how any of this works. It is quite confusing.

Some screenshots with Jupiter more or less positioned East: image image image

I also notice that the App is in German (I live in a German speaking part of Switzerland) but stellarium-web is always English. No problem for me but I just noticed it and some might prefer another language.

chuck-henebry commented 12 months ago

This explains why the app observes Daylight Savings even when I change my location within the app to India or Japan, both countries that don't observe DST. That had confused me!

If I change my OS system settings to show my location as India or Japan, the Stellarium web app stops observing DST!