About lunartime.org
A reference site on lunar timekeeping, published by an editorial desk, with a source on every number and a model label on every clock value.
Key facts
- No lunar time scale has been realized. Every lunar clock value on this site is a model value computed from the published definitions. [1]
- The rate we compute with, 56.02 µs per day for a selenoid clock against a geoid clock, comes from a peer-reviewed NIST paper of 12 August 2024. [2]
- The name Coordinated Lunar Time comes from a United States policy memorandum of 2 April 2024, not from this site. [3]Official
- Lunar time reaches the 28th CGPM as Draft Resolution D, item 17 on the provisional agenda. [4]Official
What this site is
lunartime.org is a reference site about lunar timekeeping. It follows one subject: what a lunar time scale would be, who is deciding it, and what has actually been decided so far.
Three pages carry most of that work. The lunar clock shows the model values, the standards tracker shows where each organisation stands, and the primary documents show the texts themselves. The timeline puts those texts in order, the organizations file says who holds which decision, and the glossary defines the abbreviations they use.
Every lunar clock value on this site is a model value. It is arithmetic on a published rate figure, not a reading taken from a clock standing on the Moon, because no such clock is being read into a time scale [5]Official. The working is set out in full in how we calculate lunar time.
Who writes it
Pages are written and checked by Lunartime Editorial. Lunartime Editorial is the editorial signature of the organisation that publishes this site, not the name of a person. There is no individual behind the byline, no author biography, and none is implied.
We say this plainly because the alternative is worse. Inventing a named expert
with a fabricated résumé would make the site look more authoritative and be a
lie. In schema.org markup the same choice holds: the author of every page is an
Organization, never a Person.
How we source
Every quantitative claim on the site carries a citation to a document in our source registry. The registry stores the title, the issuer, the publication date and the date on which we last opened the URL and confirmed it still says what we say it says.
Documents come first, coverage second. Where a press report and the underlying memorandum disagree, we follow the memorandum and say so on the page. Where two primary sources disagree — the CGPM convocation and the CIPM outcomes page order the draft resolutions differently — we show both and name the one we treat as authoritative [4]Official.
Numbers we work out ourselves are cited too, as our own calculation, and the formula behind them is published [1]. Rate figures we did not derive are cited to the paper that published them: 56.02 µs per day between a selenoid clock and a geoid clock comes from Ashby and Patla at NIST [2], and the epoch of Lunar Coordinate Time comes from IAU Resolution II of 2024 [6]Official.
Short answers to the questions readers ask most, each with its own source, are collected in the lunar time FAQ.
Corrections
When a published fact turns out to be wrong, we change the page and record the change here: the date, the page, what it said before, and what it says now. We do not quietly edit and move on.
No corrections yet.
What we do not cover
This site does not publish anything about how the Moon looks from Earth on a given night, about calendars built on the Moon’s cycle around Earth, or about astrology. Those subjects have their own audience and their own sites.
We also do not publish predictions dressed as facts. Where a decision has not been taken, the page says that it has not been taken, and the tracker shows the stage each organisation has actually reached.
Licensing
Text on this site is © Lunartime Editorial. Diagrams are published under CC BY 4.0: reuse them anywhere, including commercially, as long as you credit lunartime.org and say if you changed them. The diagram files themselves, with the credit line to put under them, are on the press kit.
Quotations from primary documents belong to the bodies that issued them and are reproduced here for reference, with the document named and linked at the point of quotation. Data extracted from those documents — dates, rate figures, resolution numbers — is fact, not our property; take it and cite the issuer.
Contact
Press enquiries go to press@lunartime.org, and what that address is for is set
out in the press kit, together with the figures we are willing to be
quoted on and the diagrams we license for reuse. There is still no contact form
and no social account on this site: a form that goes nowhere is worse than no
form at all. When another working channel exists, it will be listed here.
Sources
- Our calculation: the lunartime.org clock model
- A Relativistic Framework to Estimate Clock Rates on the Moon
- Policy on Celestial Time Standardization
- Convocation of the 28th meeting of the CGPM (O/Ref AK-CFA-2026-1001)
- Resolution to establish a standard Lunar Celestial Reference System (LCRS) and Lunar Coordinate Time (TCL)
- Resolution on the establishment of a coordinated lunar time standard by international agreement
Last verified