Rejoice, leap seconds are dead!
Comments on “Rejoice, leap seconds are dead!”
Claim-checked. Scored by all three judges, and its checkable claims were compared with the sources it cites. How far stories are checked
The General Conference on Weights and Measures passed Resolution 5, ending UTC leap seconds from May 20, 2027, ahead of the 2035 date set in 2022. UTC stays 37 seconds ahead of TAI and may drift up to an hour from Earth-rotation time. Engineers avoid an untested negative leap second and can eventually drop leap-second handling code. One open issue is that WWV's DUT1 broadcast assumes an offset under one second. The post's 30% negative-leap-second estimate and the 2035 comparison could not be verified.
Why it ranked
No. 15 of 111 with a score of 0.65. The panel rated it highest on new information (0.93) and audience breadth (0.77), lowest on technical depth (0.60). Placed No. 15, No. 29 by score alone: the placement terms moved other stories past it.
- AI judgeJudge 2claude-haiku-5-5
- Covers a real, consequential decision ending UTC leap seconds, with clear explanation of implications for software and time systems. Coverage is a blog-style explainer with limited primary sourcing and little deep technical detail.
- AI judgeJudge 3gpt-5.6-luna
- A well-supported explanation of UTC’s leap-second policy change, its operational consequences, and implications for computing infrastructure. Broadly relevant and practically useful, though mostly analysis rather than a reproducible technical contribution.
Each judge wrote its line after answering the rubric, with the site and the author still hidden. Every answer behind this is in the table under Score.
Score
0.65total under rubric v2.3
- Significance0.65
- Reader interest0.70
- Audience breadth0.77
- Practical relevance0.65
- Substantiated0.62
- Technical depth0.60
- New information0.93
- Counts against: Promotional0.05
- Counts against: Overclaim0.32
Each judge’s answer per question (0–1), their mean and spread, and what the question adds to the score (weight × mean).
| Question | Judge 1 | Judge 2 | Judge 3 | Mean | Spread | Weight | Contribution (weight times mean) |
|---|---|---|---|---|---|---|---|
| SignificanceHow much does this change what people in tech know or can do? | 0.71 | 0.62 | 0.62 | 0.65 | 0.09 | +0.24 | +0.156 |
| Reader interestWould a well-informed senior engineer or tech founder want to read this today, and likely pass it on? | 0.50 | 0.80 | 0.80 | 0.70 | 0.30 | +0.26 | +0.182 |
| Audience breadthHow many people who build technology does it concern? | 0.90 | 0.70 | 0.72 | 0.77 | 0.20 | +0.13 | +0.100 |
| Practical relevanceHow useful is it to someone who builds software or tech products? | 0.67 | 0.60 | 0.68 | 0.65 | 0.08 | +0.22 | +0.143 |
| SubstantiatedHow well is it backed? Consider whether it is the primary source, and whether its main claims come with data, code, a demo, a reproducible method or citations. | 0.57 | 0.60 | 0.70 | 0.62 | 0.13 | +0.05 | +0.031 |
| Technical depthHow technically substantive is it? | 0.71 | 0.50 | 0.58 | 0.60 | 0.21 | +0.05 | +0.030 |
| New informationDoes it contain information absent from the stories covered in the last 7 days (list provided)? | 0.94 | 0.90 | 0.96 | 0.93 | 0.06 | +0.05 | +0.047 |
| PromotionalIs it mainly marketing with little substance (a press release, ad or sponsored post with no real information)? A launch post that carries real news is not promotional. | 0.07 | 0.05 | 0.02 | 0.05 | 0.05 | −0.19 | −0.009 |
| OverclaimDo the headline or conclusions claim more than the body supports? | 0.56 | 0.20 | 0.20 | 0.32 | 0.36 | −0.11 | −0.035 |
| Sum of contributions | +0.645 | ||||||
| Claim-check penalty | 0.000 | ||||||
| Total, as published | 0.645 | ||||||
Spread is the highest minus the lowest judge answer. marks a spread above 0.40: the judges disagree, and the story is marked contested.
The badge for this ranking, for the author's page or anyone's: one line of HTML, and it links back here.
<a href="https://rubric.hrih.si/editions/2026-10-31/15/"><img src="https://rubric.hrih.si/badge/2026-10-31/15.svg" alt="Ranked #15 on Rubric, 31 Oct 2026" width="245" height="28"></a>Claim check
Claim check: 3 matches source · 1 no source given · 4 couldn’t check. Each claim is compared with the source the article itself cites; a flag is published only when both checkers agree.
Matches sourceDate
The last leap second for UTC occurred at the end of 2016.
The cited source says the same thing.
The article says “the last leap second we'll ever see for UTC, or Coordinated Universal Time, happened back at the end of 2016”
The source says “On July 6, 2016 the IERS announced that another leap second has been scheduled for UTC midnight at the end of December 31, 2016”
Source cited by the article: kb.meinbergglobal.com/kb/time_sync/leap_seconds/leap_second_announcement_2016
Couldn’t checkDate
The CGPM passed Resolution 5, ending the leap second 8 years earlier than the 2035 deadline set at its 2022 meeting.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “This year, they passed Resolution 5, killing the leap second 8 years earlier than the 2035 deadline they had set in their 2022 meeting”
The source says No passage could be compared.
Source cited by the article: bipm.org/en/cgpm-2022/resolution-4
Matches sourceDate
Starting on May 20, 2027, UTC will never have another leap second added or taken away.
The cited source says the same thing.
The article says “Starting on May 20, 2027, UTC will never have another leap second added or taken away”
The source says “continuous UTC will become effective on 20 May 2027”
Source cited by the article: bipm.org/en/cgpm-2026/resolution-5
Couldn’t checkNumber
UTC will be allowed to deviate from UT1 by up to 1 hour.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “UTC will be allowed to deviate from UT1, the Earth rotation time, for up to 1 hour”
The source says No passage could be compared.
Source cited by the article: bipm.org/en/cgpm-2026/resolution-5
Couldn’t checkCausal conclusion
There was a 30% chance a negative leap second would be needed between now and 2035 because Earth's rotation has been accelerating.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “there was a 30% chance we'd need a negative leap second between now and 2035, because the Earth's rotation is has been accelerating lately”
The source says No passage could be compared.
Source cited by the article: sciencefocus.com/planet-earth/earth-rotation-speed
No source givenNumber
27 positive leap seconds have been added between 1972 and today, and none has ever been removed.
The article gives no link or citation for it.
The article says “We've had 27 positive leap seconds between 1972 and today, but we've never taken one off”
The source says No source to compare with.
Matches sourceQuote
The resolution states that industrial users and critical infrastructure require UTC to be continuous without any future adjustment.
The cited source says the same thing.
The article says “Industrial users and the synchronization needs of national critical infrastructures, for example transportation, energy distribution, telecommunication, and space projects require UTC to be continuous without any future adjustment”
The source says “industrial users and the synchronization needs of national critical infrastructures, for example transportation, energy distribution, telecommunication, and space projects require UTC to be continuous without any future adjustment”
Source cited by the article: bipm.org/en/cgpm-2026/resolution-5
Couldn’t checkCausal conclusion
Meta, AWS and Google spent heavily building time smearing features for positive leap seconds and still ran into problems.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “Companies like Meta, AWS, and Google spent tons of money building 'time smearing' features into their infrastructure to deal with positive leap seconds, and they still ran into problems”
The source says No passage could be compared.
Source cited by the article: engineering.fb.com/2022/07/25/production-engineering/its-time-to-leave-the-leap-second-in-the-past
Also covered by
No other coverage was clustered with this story.
Elsewhere
Elsewhere: HN —
Recorded for context only, checked 31 Oct 2026, 05:46 UTC. It played no part in the ranking.