diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9809cb44ad3fdf1a3b6df1c9c391a7e25084872f..593e16b10a78b233863a51c53a789d2fc5457f53 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,7 @@
 - 
 
 ### Changed
-- 
+- Updates the bilby.core.utils constants to match those of Astropy v3.0.4
 
 ### Removed
 -
diff --git a/bilby/core/utils.py b/bilby/core/utils.py
index b23872827115c551b391e591648f904d7d6b7869..ce634a6e1964ab8866ae8cf5ec46bc7123d05718 100644
--- a/bilby/core/utils.py
+++ b/bilby/core/utils.py
@@ -13,12 +13,12 @@ from scipy.interpolate import interp2d
 
 logger = logging.getLogger('bilby')
 
-# Constants
 
-speed_of_light = 299792458.0  # speed of light in m/s
-parsec = 3.085677581 * 1e16
-solar_mass = 1.98855 * 1e30
-radius_of_earth = 6371 * 1e3  # metres
+# Constants: values taken from astropy v3.0.4
+speed_of_light = 299792458.0  # m/s
+parsec = 3.0856775814671916e+16  # m
+solar_mass = 1.9884754153381438e+30  # Kg
+radius_of_earth = 6378100.0  # m
 
 
 def infer_parameters_from_function(func):
diff --git a/test/gw_likelihood_test.py b/test/gw_likelihood_test.py
index 4d343a04f85526bc71b2a8df6b0a66027c48c433..b2d9a8128a0c2dcfa0089747dbd2d8a727a9422d 100644
--- a/test/gw_likelihood_test.py
+++ b/test/gw_likelihood_test.py
@@ -42,7 +42,7 @@ class TestBasicGWTransient(unittest.TestCase):
         """Test log likelihood matches precomputed value"""
         self.likelihood.log_likelihood()
         self.assertAlmostEqual(self.likelihood.log_likelihood(),
-                               -4055.2526551677647, 3)
+                               -4055.236283345252, 3)
 
     def test_log_likelihood_ratio(self):
         """Test log likelihood ratio returns the correct value"""
@@ -111,7 +111,7 @@ class TestGWTransient(unittest.TestCase):
         """Test log likelihood matches precomputed value"""
         self.likelihood.log_likelihood()
         self.assertAlmostEqual(self.likelihood.log_likelihood(),
-                               -4055.2526551677647, 3)
+                               -4055.236283345252, 3)
 
     def test_log_likelihood_ratio(self):
         """Test log likelihood ratio returns the correct value"""
diff --git a/test/utils_test.py b/test/utils_test.py
index 9b3abf9414755f6e641397caa653a1e452a4ae69..ad1d22783215bcfc00c356df2176548931b4ef3d 100644
--- a/test/utils_test.py
+++ b/test/utils_test.py
@@ -2,11 +2,27 @@ from __future__ import absolute_import, division
 
 import unittest
 import numpy as np
+from astropy import constants
 
 import bilby
 from bilby.core import utils
 
 
+class TestConstants(unittest.TestCase):
+
+    def test_speed_of_light(self):
+        self.assertTrue(bilby.core.utils.speed_of_light, constants.c.value)
+
+    def test_parsec(self):
+        self.assertTrue(bilby.core.utils.parsec, constants.pc.value)
+
+    def test_solar_mass(self):
+        self.assertTrue(bilby.core.utils.solar_mass, constants.M_sun.value)
+
+    def test_radius_of_earth(self):
+        self.assertTrue(bilby.core.utils.radius_of_earth, constants.R_earth.value)
+
+
 class TestFFT(unittest.TestCase):
 
     def setUp(self):