diff --git a/tests/test_ognutils.py b/tests/test_ognutils.py
index c98bc58..d8173ff 100644
--- a/tests/test_ognutils.py
+++ b/tests/test_ognutils.py
@@ -35,14 +35,17 @@ class TestStringMethods(unittest.TestCase):
         self.assertEqual(country_code, None)
 
     def test_wgs84_to_sphere(self):
-        lat1 = 48.74435
-        lon1 = 9.578
-        alt1 = 929
-        lat2 = 48.865
-        lon2 = 9.2225
-        alt2 = 574
+        # receiver
+        lat1 = 48.865
+        lon1 = 9.2225
+        alt1 = 574
+
+        # aircraft beacon
+        lat2 = 48.74435
+        lon2 = 9.578
+        alt2 = 929
 
         [radius, theta, phi] = wgs84_to_sphere(lat1, lat2, lon1, lon2, alt1, alt2)
         self.assertAlmostEqual(radius, 29265.6035812215, 5)
         self.assertAlmostEqual(theta, 0.694979846308314, 5)
-        self.assertAlmostEqual(phi, -62.604956, 5)
+        self.assertAlmostEqual(phi, 117.1275408121, 5)