From 50856eb8565ec2fdd80a34bd3169d635c602c643 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 1 Mar 2023 11:45:00 -0800
Subject: [PROPOSED] Mention lunar timescale effort
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* theory.html: Mention the ESA’s effort on lunar timescales.
(Thanks to Tim McBrayer.)
---
 theory.html | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/theory.html b/theory.html
index 88bf7203..04706009 100644
--- a/theory.html
+++ b/theory.html
@@ -1361,7 +1361,15 @@ They sometimes disagree.
 </section>
 
 <section>
-  <h2 id="planets">Time and time zones on other planets</h2>
+  <h2 id="planets">Time and time zones off Earth</h2>
+<p>
+The European Space Agency is <a
+href='https://www.esa.int/Applications/Navigation/Telling_time_on_the_Moon'>considering</a>
+the establishment of a reference timescale for the Moon, which has
+days roughly equivalent to 29.5 Earth days, and where relativistic
+effects cause clocks to tick slightly faster than on Earth.
+</p>
+
 <p>
 Some people's work schedules have used
 <a href="https://en.wikipedia.org/wiki/Timekeeping_on_Mars">Mars time</a>.
-- 
2.37.2