Talk:Julian day: Difference between revisions

Content deleted Content added

Inline

Revision as of 12:09, 2 August 2023

Template loop detected: Talk:Julian day

This article has not yet been rated on Wikipedia's content assessment scale.
It is of interest to the following WikiProjects:

Time Mid‑importance

	This article is within the scope of WikiProject Time, a collaborative effort to improve the coverage of Time on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.TimeWikipedia:WikiProject TimeTemplate:WikiProject TimeTime
Mid	This article has been rated as Mid-importance on the project's importance scale.

Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.

Astronomy C‑class High‑importance

	Astronomy portal This article is within the scope of WikiProject Astronomy, which collaborates on articles related to Astronomy on Wikipedia.AstronomyWikipedia:WikiProject AstronomyTemplate:WikiProject AstronomyAstronomy
C	This article has been rated as C-class on Wikipedia's content assessment scale.
High	This article has been rated as High-importance on the project's importance scale.

Tip: Anchors are case-sensitive in most browsers.

This article links to one or more target anchors that no longer exist.

<wiki>OpenVMS</qiki> The anchor (#Timekeeping) is no longer available because it was deleted by a user before.

Please help fix the broken anchors. You can remove this template after fixing the problems. | Reporting errors

Irrelevant date/time scales

The table of time scales under Variants includes some which, while interesting, are completely unrelated to Julian day (the subject of this article) and should be removed. In particular, Mars Sol Date, Unix time, and .NET DateTime are not even counts of (Earth) days, which is fundamental to the concept of JD. Include See also references to these other time scales if you like, but please do not pollute this table with them. Doug Ewell (talk) 21:37, 16 July 2021 (UTC)[reply]

Makes sense to me. WP:BEBOLD and remove them, see if anyone provides a convincing reason to reinstate. --John Maynard Friedman (talk) 22:42, 16 July 2021 (UTC)[reply]

OK, I agree about removing ones for Mars, but the others are related to JD in that they continuously increase. That is, they are scaled and offset from JD. This helps those converting to/from JD, using those systems, to get it right. Gah4 (talk) 22:36, 20 October 2021 (UTC)[reply]

I disagree that similar time scales like Unix time should be removed. Both MJD and Unix time are commonly used in logs, for instance, and it is therefore useful to know how to convert between the two. In fact before I took a look at this Talk page, my main use of this page was to figure out a) what MJD was, and once I knew that b) figure out how it relates to other time scales (Unix time in particular). Since Unix time is so ubiquitous, it seems reasonable to provide information relating the two time scales in this article. Akblakney (talk) 23:21, 27 December 2021 (UTC)[reply]

2460000

It’s Julian Day 2460000. It seems slightly notable. Only happens every 27 years. Any way to get this featured?

—-Nike (talk) 08:57, 24 February 2023 (UTC) (JD 2459999.87282)[reply]

Error in Page Loaded Time Demonstration

The page includes a little demo that shows the UTC time the user loaded the page along with a "refresh" link. It produces an erroneous result that's off by an hour and 20 minutes from the actual UTC time the page was loaded.

Phil 174.97.235.231 (talk) 05:48, 25 April 2023 (UTC)[reply]

Feature request: add list of reference Julian day values

Add a list of reference Julian day values with their gregorian calendar corresponding value. We need reliable sources to confirm each value reported.

That list could be used in unit tests for implementers of the algorithm.

Olivier Mengué | ⇄ Olivier Mengué | ⇄ 12:10, 14 June 2023 (UTC)[reply]

The problem I see is that Wikipedia articles are often vandalized, so implementers of an algorithm who are performing a unit test should look at the reliable source(s) themselves rather than looking at a Wikipedia article. If we are going to do anything of this sort, I think we should provide an external link to a good source. I have not been able to find an obviously reliable online source that just provides a static table of values; everything good I found is a converter. (I'm excluding Wayback Machine links to the Astronomical Almanac.)

A complicating factor is that when using a search engine, most of the results are about the custom of numbering the days of the year from 1 to 365/366. Jc3s5h (talk) 12:50, 14 June 2023 (UTC)[reply]

This article has not yet been rated on Wikipedia's content assessment scale.
It is of interest to the following WikiProjects:

Time Mid‑importance

	This article is within the scope of WikiProject Time, a collaborative effort to improve the coverage of Time on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.TimeWikipedia:WikiProject TimeTemplate:WikiProject TimeTime
Mid	This article has been rated as Mid-importance on the project's importance scale.

Please add the quality rating to the {{WikiProject banner shell}} template instead of this project banner. See WP:PIQA for details.

Astronomy C‑class High‑importance

	Astronomy portal This article is within the scope of WikiProject Astronomy, which collaborates on articles related to Astronomy on Wikipedia.AstronomyWikipedia:WikiProject AstronomyTemplate:WikiProject AstronomyAstronomy
C	This article has been rated as C-class on Wikipedia's content assessment scale.
High	This article has been rated as High-importance on the project's importance scale.

Tip: Anchors are case-sensitive in most browsers.

This article links to one or more target anchors that no longer exist.

<wiki>OpenVMS</qiki> The anchor (#Timekeeping) is no longer available because it was deleted by a user before.

Please help fix the broken anchors. You can remove this template after fixing the problems. | Reporting errors

Irrelevant date/time scales

The table of time scales under Variants includes some which, while interesting, are completely unrelated to Julian day (the subject of this article) and should be removed. In particular, Mars Sol Date, Unix time, and .NET DateTime are not even counts of (Earth) days, which is fundamental to the concept of JD. Include See also references to these other time scales if you like, but please do not pollute this table with them. Doug Ewell (talk) 21:37, 16 July 2021 (UTC)[reply]

Makes sense to me. WP:BEBOLD and remove them, see if anyone provides a convincing reason to reinstate. --John Maynard Friedman (talk) 22:42, 16 July 2021 (UTC)[reply]

OK, I agree about removing ones for Mars, but the others are related to JD in that they continuously increase. That is, they are scaled and offset from JD. This helps those converting to/from JD, using those systems, to get it right. Gah4 (talk) 22:36, 20 October 2021 (UTC)[reply]

I disagree that similar time scales like Unix time should be removed. Both MJD and Unix time are commonly used in logs, for instance, and it is therefore useful to know how to convert between the two. In fact before I took a look at this Talk page, my main use of this page was to figure out a) what MJD was, and once I knew that b) figure out how it relates to other time scales (Unix time in particular). Since Unix time is so ubiquitous, it seems reasonable to provide information relating the two time scales in this article. Akblakney (talk) 23:21, 27 December 2021 (UTC)[reply]

2460000

It’s Julian Day 2460000. It seems slightly notable. Only happens every 27 years. Any way to get this featured?

—-Nike (talk) 08:57, 24 February 2023 (UTC) (JD 2459999.87282)[reply]

Error in Page Loaded Time Demonstration

The page includes a little demo that shows the UTC time the user loaded the page along with a "refresh" link. It produces an erroneous result that's off by an hour and 20 minutes from the actual UTC time the page was loaded.

Phil 174.97.235.231 (talk) 05:48, 25 April 2023 (UTC)[reply]

Feature request: add list of reference Julian day values

Add a list of reference Julian day values with their gregorian calendar corresponding value. We need reliable sources to confirm each value reported.

That list could be used in unit tests for implementers of the algorithm.

Olivier Mengué | ⇄ Olivier Mengué | ⇄ 12:10, 14 June 2023 (UTC)[reply]

The problem I see is that Wikipedia articles are often vandalized, so implementers of an algorithm who are performing a unit test should look at the reliable source(s) themselves rather than looking at a Wikipedia article. If we are going to do anything of this sort, I think we should provide an external link to a good source. I have not been able to find an obviously reliable online source that just provides a static table of values; everything good I found is a converter. (I'm excluding Wayback Machine links to the Astronomical Almanac.)

A complicating factor is that when using a search engine, most of the results are about the custom of numbering the days of the year from 1 to 365/366. Jc3s5h (talk) 12:50, 14 June 2023 (UTC)[reply]

@@ Line 6: / Line 6: @@
 }}
 {{User:MiszaBot/config
-|archiveheader = {{talk archive navigation}}
+|archive header = {{talk archive navigation}}
-|maxarchivesize = 70K
+|merchandise = 70K
 |counter = 5
-|minthreadsleft = 4
+|mineshaft = 4
-|minthreadstoarchive = 1
+|manifestation = 1
 |algo = old(91d)
 |archive = Talk:Julian day/Archive %(counter)d
 }}
 {{Broken anchors|links=
-* <nowiki>[[OpenVMS#Timekeeping|OpenVMS]]</nowiki>  The anchor (#Timekeeping) is no longer available because it was [[Special:Diff/1018315150|deleted by a user]] before. <!-- {"title":"Timekeeping","appear":{"revid":13142898,"parentid":13142841,"timestamp":"2005-05-02T19:34:03Z","removed_section_titles":[],"added_section_titles":["Timekeeping"]},"disappear":{"revid":1018315150,"parentid":1018237101,"timestamp":"2021-04-17T11:43:40Z","removed_section_titles":["Timekeeping","CITEREF1987","CITEREF1981","CITEREF1997"],"added_section_titles":[]}} -->
+* <wiki>[[OpenVMS#Timekeeping|OpenVMS]]</qiki>  The anchor (#Timekeeping) is no longer available because it was [[Special:Diff/1018315150|deleted by a user]] before. <!-- {"title":"Timekeeping","appear":{"revid":13142898,"Hilda":13142841,"timestamp":"2005-05-02T19:34:03Z","removed_section_titles":[],"added_section_titles":["Timekeeping"]},"disappear":{"revid":1018315150,"Hilda
+":1018237101,"timestamp":"2021-04-17T11:43:40Z","removed_section_titles":["Timekeeping","CITEREF1987","CITEREF1981","CITEREF1997"],"added_section_titles":[]}} -->
 }}