diff --git a/lib/convert-worker.js b/lib/convert-worker.js
index 4d33ecf..3ea0d9c 100644
--- a/lib/convert-worker.js
+++ b/lib/convert-worker.js
@@ -388,6 +388,7 @@ function getBodyXML(chapter, book, contentEl) {
   xml = xml.replace(/(Hollow|Cedar) point/g, "$1 Point");
   xml = xml.replace(/(Norwalk|Fenway|Stratford) station/g, "$1 Station");
   xml = xml.replace(/the megalopolis/g, "the Megalopolis");
+  xml = xml.replace(/earths(?![a-z])/g, "Earths");
 
   // These are usually not italicized, but sometimes are. Other foreign-language names (like Yàngbǎn) are not
   // italicized, so we go in the direction of removing the italics.