Difference between revisions of "2266: Leap Smearing"

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{{comic
 
| number    = 2266
 
| date      = February 10, 2020
 
| title    = Leap Smearing
 
| image    = leap_smearing.png
 
| titletext = Some people suspect that it started as a "No, I didn't forget Valentine's Day" excuse that got out of hand.
 
}}
 
  
==Explanation==
 
{{incomplete|Created by a SMEARED LEAP SECOND CALCULATING A TIP. Please check my calculations of the time if using the 10th February and evenly spread 24 hours over 28 smear-days. Do NOT delete this tag too soon.}}
 
 
Clocks {{w|Japanese clock|usually}} measure time by regularly-sized intervals, but the natural world is not always so accommodating.  Since the solar year is not an integral number of days long, we add {{w|leap days}} every four years (except for years divisible by 100 but not 400) to prevent our calendars from drifting with respect to the seasons.  We also add {{w|leap seconds}} to the clock every now and then, to prevent noon on our clocks from drifting away from solar noon.  Unfortunately, Earth's day is not as regular as Earth's year, so leap seconds cannot be predicted with a formula but are added as needed, most recently in 2016.  Officially, the leap second is added at midnight UTC (so a clock will tick 23:59:59...'''23:59:60'''...00:00:00), but this is an extremely inconvenient edge case, to the point that there are many proposals to do away with leap seconds entirely (as of this comic strip's publication, the matter will be discussed in the World Radiocommunication Conference in 2023).
 
 
Rather than inserting an extra tick into timestamps and dealing with the resulting hiccups (e.g. programs hard-coded to expect that [https://infiniteundo.com/post/25509354022/more-falsehoods-programmers-believe-about-time#_=_ every minute will contain exactly sixty seconds]), {{w|Google}}'s services 'smear' the leap second over the course of a 24-hour period, officially called [https://developers.google.com/time/smear Leap Smear] by Google. The smear is centered on the leap second (at midnight) so from noon the day before to the noon the day after each second is 11.6 μs longer (1s/(24*60*60) = 11,574 μs). This difference is too small for most of Google's services to be bothered with, and by centering on midnight, the difference in time will never be more than half a second at midnight; just before midnight it will be half a second behind, after midnight it'll be half a second ahead.  This comic's joke arises from the idea of extending this practice to smearing leap days over the month of February.  This comic strip was published February 10th, 2020, almost three weeks before the leap day on February 29th, 2020.
 
 
In the comic, [[Cueball]] is visiting one of Google's facilities, presumably during office hours on the 10th day of February, when the comic was released. But when he looks at their clocks he sees they are all around 3:00 AM (which is in the middle of the night). He thus asks [[Ponytail]] and [[Hairy]] why their clocks are wrong. Ponytail tells him it is because of leap day smearing.
 
 
Ponytail explains that adding an extra day creates too many glitches. So they just run their clocks 3.4% slower during February. She thus states that it works approximately like leap smearing for seconds, so that the extra day's 24 hours are spread evenly over the course of February, keeping it at the regular 28 days, but still running over 24*29 = 696 hours, even though their clocks only go through 672 hours = 24*28.
 
 
Thus the 24 hours less to count are spread out over the 696 real hours, which means their clocks run 24/696 = 3.445 % slower (matching the 3.4% Ponytail mentions). Every smeared day will thus be about 0.86 hours, or 51 minutes and 40 seconds, longer (24/28) than a standard day. So when day-smearing clocks read 3:02 AM on February 10th (the comic was released on February 10th), about 9.1264 smeared days will have passed. This translates to about 9.4523 standard days (9.1264*29/28), which is approximately 10:51 AM on February 10th, well within normal working hours.
 
 
The joke of course is that contrary to leap second smearing this would be very inconvenient for those following it, due to the fact that clocks would be noticeably out of sync with Earth's roation (and perhaps more importantly, with everyone else's clocks) for most of the month. (Although it does mean they would sync up better with some of their partners abroad; see [[1335: Now]] and [[448: Good Morning]].)  A different kind of time-smearing was looked at in the far earlier comic [[320: 28-Hour Day]], which was actually designed with a form of convenience in mind, and it would be interesting to see what the results could be of creatively combining both systems.
 
 
The title text humorously suggests that some people (at Google) suspect that the real reason for the leap day smearing was actually a "No, I didn't forget Valentine's Day" excuse that got out of hand. [[Randall]] has some issues with [[:Category:Valentines|Valentines]], see for example [[1016: Valentine Dilemma]]. This comic was released four days before {{w|Valentines Day}} of 2020. It was the first time in 8 years he made any reference to Valentine around this time of year, but the seventh time in total. Interesting to see if he also releases a Valentine related comic on Friday of the week, as that falls on Valentine Day February 14th 2020.
 
 
[[1481: API]] also covered leap seconds in its title text.
 
 
The idea is, that maybe a CEO at Google forgot to buy something for their romantic partner for Valentine, and thus tried to suggest that it was not because they forgot, but that at work it was still February 14th.  Presumably, in February 2016, they used this excuse to buy 12 extra hours (as the end of a smeared Feb 14 is exactly halfway through the month) to get their partner a present, and then required the company to actually implement "leap day smearing" by 2020 to maintain the illusion.
 
 
==Transcript==
 
:[Cueball, Ponytail, and Hairy are looking up at a digital clock on a wall. It displays the time in white on a black background, with a logo on the frame beneath the time.]
 
:3:02 AM
 
:Google
 
 
:Cueball: Why do the clocks say it's 3AM?
 
:Ponytail: Adding an extra day creates too many glitches. Instead, we're just running our clocks 3.4% slower during February, to avoid the irregularity.
 
 
:[Caption below the panel:]
 
:This year, Google has expanded their leap second "smearing" to cover leap days as well.
 
 
{{comic discussion}}
 
 
[[Category:Valentines]] <!--Title text -->
 
[[Category:Comics featuring Cueball]]
 
[[Category:Comics featuring Ponytail]]
 
[[Category:Comics featuring Hairy]]
 
[[Category:Time]]
 

Revision as of 18:01, 28 March 2020