2897: Light Leap Years

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Light Leap Years

Title text: When Pope Gregory XIII briefly shortened the light-year in 1582, it led to navigational chaos and the loss of several Papal starships.

Explanation

This explanation may be incomplete or incorrect: Created by a LIGHT LEAP SECOND - Please change this comment when editing this page. Do NOT delete this tag too soon. If you can address this issue, please edit the page! Thanks.

A light year is a length unit that is defined as how much light will travel in a vacuum during a year; however, the year used is the average Julian year, or 365.25 days. In this comic, however, Randall works with the assumption that a light year is based on the length of the current year, which means that during leap years, it uses 366 days, and during non-leap years, it uses 365 days. That means that at the start and end of leap years, databases with astronomical distances have to be adjusted.

2024 is a leap year in the Gregorian calendar used in most parts of the world.

This comic portrays Cueball and Ponytail updating astronomical distances in some sort of database, noting how long and unpleasant the process is, the caption reveals that the reason is that leap years "make light-years 0.27% longer.

A light year is a unit of distance, common used in astronomy, equivalent to the distance light travels in a vacuum in one year. The joke of this strip is based on the fact that "one year" isn't a precise unit of measurement, there are different definitions of what what constitute a year, which have evolved over time, and which vary among themselves. The Gregorian calendar (the most commonly used in modern times) includes a system of "leap years" in which an additional day is added every fourth year (with some exceptions) to make up for inconsistencies between day and year cycles. This temporarily changes the length of a year from 365 to 366 days, which could be taken to change the length of a light year.

Standardized systems of measurement naturally don't change continually. As the comic points out, the difficulty in having to regularly update every reference to these units would be enormous and pointless. In real life, a light year is defined by the Julian Year, which is defined as 365.25 days, with each day being 86,400 SI seconds in length. This results in a light year which is standardized at 9,460,730,472,580.8 km, no matter how long the calendar year may be.

The rollover text jokes that Pope Gregory XIII, the originator of the Gregorian calendar, "briefly shortened the light-year in 1582, which led to "navigational chaos and the loss of several papal starships". This, of course, is ludicrous, as there were no starships in the 16th century, there's never been a "papal starship", and the light-year wasn't developed as a unit of measurement until 1838. The joke is that the evolving and somewhat loose and changing definitions of early calendars had significant impacts on the units of measurement we still use today. Such changes were of only minor significance at the time, but as technology has advanced and become more reliant on precise and consistent measurements, such changes could be disastrous.

Transcript

This transcript is incomplete. Please help editing it! Thanks.

[Cueball sitting at his laptop and leaning to the back of his office chair, while looking at Ponytail who is standing behind him.]

Cueball: It took until February, but I finally got all the distances updated!

Ponytail: I really wish we didn't have to do this.

[Laptop screen:]

Proxima Centauri

Distance: [crossed over in red] 4.2493 ly

[in green] 4.2377 ly

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Discussion

Not that it effects the joke, but the Gregorian calendar has 97 leap years per 400 year cycle. I was surprised that I was surprised by that. 162.158.63.115 16:23, 21 February 2024 (UTC)

Another interesting number: the difference between the standard Julian year and the (AFAICT, not officially named as such) 'standard Gregorian year' (of 365.2425 days) is 648 seconds, or 10.8 minutes (10m48s) if you prefer. 172.69.194.115 00:38, 22 February 2024 (UTC)

"...never been a papal starship..." - If this upsets you, read Hyperion! 172.71.142.67 17:12, 21 February 2024 (UTC)

Even the most cursory research (i.e. googling) reveals that there have been Papal starships.172.70.90.190 09:38, 22 February 2024 (UTC)

I appreciate the {cite needed}!!! and added more adjectives (known earthly). Just because we are not aware of any, doesn't mean they don't exist! For example, how did Michelangelo get to this planet? I have my suspicions!!!;P Cuvtixo (talk) 01:57, 23 February 2024 (UTC)

Could also be a Doctor Who reference, the Papal Mainframe being a space station featuring in "The Time of the Doctor". 172.69.43.220 10:42, 23 February 2024 (UTC)

"Note: Lightsecond was chosen instead of the more familiar lightyear to make sure that layouts computed during leap years would be unambiguously identical to those computed during non-leap years." (from https://drafts.csswg.org/css-egg-1/#astro-units) --172.68.253.143 18:23, 21 February 2024 (UTC)

The last paragraph says Randall. It should say Cueball. Randall knows better otherwise he would not have made this joke. 172.71.22.98 04:02, 22 February 2024 (UTC)

I find it funny (assuming we're seeing the last edit to have been done, and Cueball's not just scrolled us up to see the very first 'diff' again) that the whole month-and-a-lot-long job has apparently finished with the changed measurement for the likely closest object in the database of thousands (or maybe even "millions and billions!") of cosmological objects. Whether or not it has extragalactic (or significantly transgalactic) record items in it, it would seem rather topsy-turvy to leave the physically nearest item's entry until last, if it was indeed consciously sorted by any distance-related parameter. (Like I could understand if it were perhaps something like Zeta Reticuli, where we ended up, more than Alpha Cassiopeiae, or maybe Z Vul at the opposite end to 'Alpha And'.) ...ok, so maybe now I'm just dissecting the frog toad, but I still think it's yet another 'layer of funny'. Whether intended (I really wouldn't put it past Randall being so deep...) or otherwise! 172.71.178.185 03:04, 24 February 2024 (UTC)

Question 1: What is incomplete about this article? Question 2: When it's complete, can we somehow preserve the papal starships from Anno Domini MDLXXXII? GreatWyrmGold (talk) 15:23, 5 March 2024 (UTC)