diff --git a/app/views/tag/rss.rss.builder b/app/views/tag/rss.rss.builder
index 965bae3ced..48b2f991d3 100644
--- a/app/views/tag/rss.rss.builder
+++ b/app/views/tag/rss.rss.builder
@@ -1,4 +1,4 @@
-xml.rss :version => '2.0', 'xmlns:atom' => 'http://www.w3.org/2005/Atom' do
+xml.rss :version => '2.0', 'xmlns:atom' => 'https://www.w3.org/2005/Atom' do
   xml.channel do
     xml.title "Research tagged '#{params[:tagname]}'"
     xml.description "Open source environmental science research at Public Lab"