diff --git a/gnu/packages/astronomy.scm b/gnu/packages/astronomy.scm
index 6ceea75553..2bbdfb58d7 100644
--- a/gnu/packages/astronomy.scm
+++ b/gnu/packages/astronomy.scm
@@ -21,6 +21,7 @@
   #:use-module (guix packages)
   #:use-module ((guix licenses) #:prefix license:)
   #:use-module (guix download)
+  #:use-module (guix utils)
   #:use-module (gnu packages image)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages gettext)
@@ -34,16 +35,18 @@
 (define-public cfitsio
   (package
     (name "cfitsio")
-    (version "3390")
+    (version "3.420")
     (source
      (origin
        (method url-fetch)
        (uri (string-append
-             "http://heasarc.gsfc.nasa.gov/FTP/software/fitsio/c/" name version
-             ".tar.gz"))
+             "http://heasarc.gsfc.nasa.gov/FTP/software/fitsio/c/"
+             name (string-replace-substring version "." "") ".tar.gz"))
        (sha256
-        (base32 "02gllydm63irwbqqisa3mrskw1fphm5rlplglz3mq9whi3rxilv2"))))
+        (base32 "1f0nmki45h9kw7vxpxiav9cb6vs3qqi6zrp2lpci5yhqc5isl43c"))))
     (build-system gnu-build-system)
+    ;; XXX Building with curl currently breaks wcslib.  It doesn't use
+    ;; pkg-config and hence won't link with -lcurl.
     (arguments
      `(#:tests? #f ; no tests
        #:phases