2266: Leap Smearing

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Leap Smearing
Some people suspect that it started as a "No, I didn't forget Valentine's Day" excuse that got out of hand.
Title text: Some people suspect that it started as a "No, I didn't forget Valentine's Day" excuse that got out of hand.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a SMEARED LEAP SECOND. Please check my calculations of the time if using the 10th February and evenly spread 24 hours over 29 days. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

This comic references the practice that Google uses on its services of 'smearing' a leap second over the course of a 24-hour period, officially called Leap Smear by Goggle. 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).

The joke arises from the idea of expanding this idea - instead of just using it for leap seconds, using it for leap days as well, like that at the end of February 2020, less than 3 weeks after this comic was released.

In the comic Cueball is visiting one of Google's facilities, presumable during office hours and in the middle of February, and when he then looks at their a clock he sees they are around 3:00 AM (in the middle of the night) and thus asks Ponytail and Hairy why their clocks are wrong. Ponytail then tells him it is because of leap day smearing.

Ponytail explains that adding an extra day creates too many glitches. So they just runs their clocks 3.4% slower during February. She thus states that it works approximately like leap smearing for seconds, so that extra days 24 hours are spread evenly out 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 goes through 672 hours (24*28). Thus the 24 hours less spread out over 696 hours means the clocks run 24/696 = 3.445 % slower (matching the 3.4% Ponytail mentions). Ever day will thus be 0.83 hours longer (24/29). So after 9 days, (the comic was released on February 10th), the clocks will be 7 hours and 27 minutes behind at midnight. Thus if such a clock is saying 3:02 AM on February 10th it would mean that the time would actually be 10:35 AM, well within working hours. The last 6 ,minutes comes from the 3 hours and 2 minutes also running 3,4% slower.

This would of course, contrary to leap second smearing, be very inconvenient for those following it, due to the fact that it would be out of sync with the rotation of the earth for most of the course of the month. And also with all their local business partners. (Of course it would mean they would sync up better with some of their partners abroad, see 1335: Now.)

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.


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Discussion

Although to be fair, leap seconds are confusing. Unpopular Opinions (talk) 04:08, 11 February 2020 (UTC)

Leap seconds are idiotic. The only people who care about keeping the Earth tied to the time are astronomers. And no one cares about them.SDSpivey (talk) 04:56, 11 February 2020 (UTC)

Oh, you'll care about leap seconds when your GPS starts failing, i assure you. 141.101.107.204 07:08, 11 February 2020‎ (UTC)
GPS does NOT have leap seconds. That's why GPS time is drifting away from UTC. It's off by about 19 seconds now, since 1980. However, people would care eventually, when the time on the clock doesn't match up with the solar day (as pointed out by the next comment.) It would take a long time, but why get started off on the wrong foot? 108.162.238.125 14:39, 12 February 2020 (UTC)
Leap seconds are a mess, but so is changing the definition of UTC and letting it drift away from solar time. There are movements to try to make this change, but there are significant obstacles. (For example, the signatories to the 1884 International Meridian Conference agreed that the civil time everyone should use is based on mean solar time, and US Federal Law indicates that the legal time of the US is based on mean solar time.) Zmatt (talk) 06:30, 11 February 2020 (UTC)
If we don't use leap seconds, then the GPS won't use them either. How many seconds difference before we humans could even notice? A century's worth or more, I'm certain. By then we could just fix the wobble of the Earth. SDSpivey (talk) 07:33, 11 February 2020 (UTC)
1. You use “we humans”, who do you think is studying and correcting with leap seconds? Robots? 2. I don’t think you realize just how quickly that would cause problems. “That Guy from the Netherlands” (talk) 12:52, 11 February 2020 (UTC)
Leap seconds are added rougly every couple of years. If we stopped, it would take about a century to be off by a minute, and 6,000 years to be off by an hour. So maybe we should just plan on every 6K years we skip Daylight Saving Time to recover that hour. Barmar (talk) 16:26, 11 February 2020 (UTC)
For half a year, then we're back to the situation we were ignoring. ;) ((Obviously, what we might need to do is move the Prime Meridian, send it on a very slow "world tour" by passing it onto the next suitable city. But I'm a bit of a conservative when it comes to historic locations, so we should just put Greenwich Observatory on wheels, or rails, if necessary.)) 162.158.154.139 23:37, 11 February 2020 (UTC)

I believe the actual time would be 11:42am (on the 11th of February). Dakranon (talk) 06:20, 11 February 2020 (UTC)

But the comic was released on 10t February Monday as always, but the date was written wrongly on the comic here. I have treid to calculate the time on February 10th. --Kynde (talk) 08:21, 11 February 2020 (UTC)

I think there is an error in the calculations given in the explanation, but it's possible some bistromathics got involved instead. By my reckoning, 24 hours smeared over 28 "days" make each "day" 24/28 hours (≈ 51 minutes, 26 seconds) longer than a day instead of 24/29. Also, conveniently for my calculations, the end of "14 February" should be exactly halfway through the month, meaning the CEO should have until exactly noon on the 15th to get away with the given excuse (12 extra hours, not 11). 172.69.33.239 10:27, 11 February 2020 (UTC)

Thanks for correcting my attempt. As I wrote in the incomplete tag I was not sure I did it right.

You guys are all missing the point! We should apply non-leap smearing to the other 11 months so that EVERY month has 28 days. No more crazy calendar day-shifting: if you were born on a Monday(e.g.) your birthday will always be Monday. Cellocgw (talk) 15:06, 11 February 2020 (UTC)

Or go even further... 162.158.155.92 17:04, 11 February 2020 (UTC)
Actually we should do as the hobbits in Tolkien's Lord of the Rings. They run 28 day months, 13 of them instead of 12 and that gives 364 days. I cannot remember the details correctly, but it is something like they then have a New Year day every year, and a leap day every four years after New Years day. The Year starts on a Monday as do all months. The New Year day (and Leap days) are not given any Weekday, so after Sunday 28th of December (or what the last month would be called) there are one or two days, without a weekday assigned, and the new year begins on Monday. It would all be soooo much more easy, but of course if you where born on a Monday you would always have your birthday on a Monday! ;-) --Kynde (talk) 12:01, 12 February 2020 (UTC)

As of right now, I feel like the explanation is a bit of a mess. I already understand this comic but IMO someone who doesn't would not be able to follow this explanation. I think a better structure would be:

  1. Briefly explain what leap seconds are, since most readers will not know about them.
  2. Explain the "smear second" approach, and mention how the resulting time deviates by only half a second at the worst time.
  3. A line like "This comic suggests taking the smear second approach and applying it to leap days"
  4. Brief explanation/reminder of what leap days are - most readers will be familiar with this concept already, and those that don't can click on a Wikipedia link to read more.
  5. Explanation of how bad the results would be (some math here), the resulting date&time would be off by 24 hours at the worst time (end of Feb 29 will appear as the end of Feb 28). It's not 12 hours because unlike the smear second, the smear period will not be centered around the leap day but rather the leap day will be at the end of the smear period (which is all of February). Also mention exactly what the clock would show on the day of this comic's publication, and what the in-comic time actually is.

--NeatNit (talk) 19:00, 11 February 2020 (UTC)

I guess this has happened more or less now? --Kynde (talk) 12:01, 12 February 2020 (UTC)

This would violate the NTP 500ppm maximum slew rate, right? ;) 173.245.54.89 (talk) (please sign your comments with ~~~~)

I really wish this was an interactive comic, with the Time changing throughout the month... 172.69.68.209 16:59, 12 February 2020 (UTC) Sam