diff --git a/propagation/perturbed_satellite_orbit.ipynb b/propagation/perturbed_satellite_orbit.ipynb
index c430dec..359a2cc 100644
--- a/propagation/perturbed_satellite_orbit.ipynb
+++ b/propagation/perturbed_satellite_orbit.ipynb
@@ -189,7 +189,7 @@
    "outputs": [],
    "source": [
     "# Create radiation pressure settings, and add to vehicle\n",
-    "reference_area = (4*0.3*0.1+2*0.1*0.1)/4  # Average projection area of a 3U CubeSat\n",
+    "reference_area_radiation = (4*0.3*0.1+2*0.1*0.1)/4  # Average projection area of a 3U CubeSat\n",
     "radiation_pressure_coefficient = 1.2\n",
     "occulting_bodies = [\"Earth\"]\n",
     "radiation_pressure_settings = environment_setup.radiation_pressure.cannonball(\n",