diff --git a/README.md b/README.md
index 164d26f..930d72d 100644
--- a/README.md
+++ b/README.md
@@ -30,7 +30,7 @@ Screenshots of Galmon Observers, generated by `galmon-observers2leaflet`.
 *Leaflet with Galmon Observer locations.*
 ![leaflet-galmon-observers](pics/leaflet-galmon-observers.png)
 
-*Leaflet with Galmon GNSS locations.*
+*Leaflet with Galmon GNSS ("GPS satellite") locations.*
 ![leaflet-galmon-gnss](pics/leaflet-galmon-gnss.png)