lunartime.org

Organization

Purple Mountain Observatory, Chinese Academy of Sciences

Chinese observatory whose group published the LTE440 lunar time ephemeris built on the IAU definition of Lunar Coordinate Time.

At a glance

Every value in this table comes from the entry in our organizations registry; the links below lead to the pages it connects to.
FieldValue
Short namePMO
TypeNational institute
BasedChina
Address we linkarxiv.org
TrackerChina — CAS / Purple Mountain Observatory
Documents on this siteNone yet
Papers on this site2 readings
Facts on this page4, each with its own source

Key facts

  • The LTE440 paper names the Purple Mountain Observatory of the Chinese Academy of Sciences as the affiliation of its authors. [1]
  • LTE440 computes the secular drift between the coordinate times as one minus 1.4825362167 by ten to the minus eighth for TCL against TCB. [1]
  • Its stated accuracy is better than 0.15 nanoseconds before 2050, with numerical precision at the level of one picosecond over the full span. [1]
  • The user manual states that LTE440 is built on the definition of Lunar Coordinate Time given in IAU 2024 Resolution II. [2]

In short

A group at the Purple Mountain Observatory published LTE440, software that computes Lunar Coordinate Time and its relations to the barycentric scales. The address on this page is the paper that names the observatory as its authors' affiliation, not the observatory's own site: we could not open a site on its domain, and we do not publish an address we have not seen. What the group has published is software and papers; no Chinese lunar time scale has been announced as realized.

Every clock value on this site is a model value computed from published rate figures: no lunar time scale has been realized, and nothing on this page is a reading taken from a clock on the Moon[3]Official. The record itself sits inthe list of organizations, and the wider background is inwhat Coordinated Lunar Time is.

What it decides

  1. How TCL is computed in practice, and with what stated accuracy, for anyone who needs the transformation today.
  2. Which ephemeris and which gravitational contributions that computation rests on.
  3. What the Chinese published position on lunar time is, as far as the papers state it.

Where this record connects

Papers we have read

On the tracker

Other organizations

Sources

  1. Lunar Time Ephemeris LTE440: definitions, algorithm and performance — Xu Lu, Tian-Ning Yang, Yi Xie, Purple Mountain Observatory, Chinese Academy of Sciences — Astronomy & Astrophysics 704, A76, . Peer-reviewed. Verified .
  2. Lunar Time Ephemeris LTE440: User Manual — Xu Lu, Tian-Ning Yang, Yi Xie — arXiv:2506.19213, . Peer-reviewed. Verified .
  3. Resolution on the establishment of a coordinated lunar time standard by international agreement — International Astronomical Union, Commission A3 — XXXII General Assembly, . Official document. Verified .
  4. Two birds with one stone: simultaneous realization of both Lunar Coordinate Time and lunar geoid time by a single orbital clock — Tian-Ning Yang, Ren-Fang Geng, Jing Zhang, Chong Yang, Yong Huang, Yi Xie — arXiv:2512.23098, . Peer-reviewed. Verified .

Last verified