Update README.rst

Author: RoryBarnes

examples/CosmicShoreline/README.rst

@@ -5,7 +5,7 @@ Overview
 --------
 
 A reproduction of Zahnle & Catling (2018)'s cosmic shoreline,
-a proposed boundary between planet with and without atmosphere.
+a proposed boundary between planets with and without atmosphere.
 
 ===================   ============
 **Date**              09/12/2024
@@ -30,9 +30,9 @@ Expected output
    :width: 100%
    :align: center
 
-The blue line is the cosmic shoreline, which is taken from Fig. 2
+The blue line is the cosmic shoreline, which is drawn by eye based on Fig. 2
 of Zahnle & Catling (2018). The black points are the positions
-of the Solar System planets in this parameter space. The Sun's XUV luminosity
+of Solar System planets. The Sun's XUV luminosity
 is assumed to follow the Ribas et al. (2005) model. This figure, while
 not as complete as Zahnle & Catling (2018), is a near exact reproduction
-of their results.
+for the planets.