Geoid

The geoid is the equipotential surface of Earth's gravity field that mean sea level follows. Terrestrial Time is the time of a clock at rest on it, which makes the geoid the reference level that lunar clock rates are quoted against.

Contrasted with
Selenoid

Other terms worth reading next.

All thirty entries are in the glossary of lunar timekeeping.

Where it appears

Primary documents that use the term.

  • NIST's relativistic framework for lunar clocks [1]

Sources

  1. A Relativistic Framework to Estimate Clock Rates on the Moon — Neil Ashby and Bijunath R. Patla, NIST — The Astronomical Journal 168:112, . Peer-reviewed. Verified .
  2. Lunar reference timescale — A Bourgoin, P Defraigne, F Meynadier — Metrologia 63(1) 015003, . Peer-reviewed. Verified .

Last verified