diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8666e84..fe40727 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,10 @@
 ## master (unreleased)
 
 * Added ``expiration_limit`` argument for ``get_skyfield_data_path`` function. Enables to shift the expiration date limit by "n" days.
+* USNO file serving host has changed. Pointing now at ``ftp://cddis.nasa.gov/products/iers/`` for ``deltat.*`` files.
+* Updated ``deltat.data`` data file.
+* Updated ``Leap_Second.dat`` data file.
+* All expiration data items are also up-to-date as of 2020-05-05.
 
 ## 0.1.0 (2019-10-04)
 
diff --git a/download.py b/download.py
index 2fde3f4..a35cd7b 100644
--- a/download.py
+++ b/download.py
@@ -12,7 +12,7 @@ from termcolor import colored
 init()
 
 JPL = "ftp://ssd.jpl.nasa.gov/pub/eph/planets/bsp"
-USNO = "http://maia.usno.navy.mil/ser7"
+USNO = "ftp://cddis.nasa.gov/products/iers/"
 IERS = "https://hpiers.obspm.fr/iers/bul/bulc"
 
 __DATA_PATH = abspath(join(dirname(__file__), "skyfield_data", "data"))
diff --git a/skyfield_data/data/Leap_Second.dat b/skyfield_data/data/Leap_Second.dat
index fc7c845..ed10c49 100644
--- a/skyfield_data/data/Leap_Second.dat
+++ b/skyfield_data/data/Leap_Second.dat
@@ -1,10 +1,10 @@
 #  Value of TAI-UTC in second valid beetween the initial value until
 #  the epoch given on the next line. The last line reads that NO
 #  leap second was introduced since the corresponding date 
-#  Updated through IERS Bulletin 58 issued in July 2019
+#  Updated through IERS Bulletin 59 issued in January 2020
 #  
 #
-#  File expires on 28 June 2020
+#  File expires on 28 December 2020
 #
 #
 #    MJD        Date        TAI-UTC (s)
diff --git a/skyfield_data/data/deltat.data b/skyfield_data/data/deltat.data
index 07b6af8..1174c84 100644
--- a/skyfield_data/data/deltat.data
+++ b/skyfield_data/data/deltat.data
@@ -555,3 +555,11 @@
  2019  4  1  69.3032
  2019  5  1  69.3326
  2019  6  1  69.3540
+ 2019  7  1  69.3582
+ 2019  8  1  69.3442
+ 2019  9  1  69.3376
+ 2019 10  1  69.3377
+ 2019 11  1  69.3432
+ 2019 12  1  69.3540
+ 2020  1  1  69.3612
+ 2020  2  1  69.3752
diff --git a/skyfield_data/expiration_data.py b/skyfield_data/expiration_data.py
index e669b1f..90373f5 100644
--- a/skyfield_data/expiration_data.py
+++ b/skyfield_data/expiration_data.py
@@ -1,3 +1,3 @@
 import datetime
 
-EXPIRATIONS = {'de421.bsp': datetime.date(2053, 10, 8), 'deltat.data': datetime.date(2020, 6, 1), 'deltat.preds': datetime.date(2021, 1, 1), 'Leap_Second.dat': datetime.date(2020, 7, 28)}
+EXPIRATIONS = {'de421.bsp': datetime.date(2053, 10, 8), 'deltat.data': datetime.date(2021, 2, 1), 'deltat.preds': datetime.date(2021, 1, 1), 'Leap_Second.dat': datetime.date(2021, 1, 27)}