How to use link_to for an external reference?

Suppose I wish to have the following link embedded in one of my

<p><a href="" target="_blank">Ruby on Rails</


How can I use the 'link_to' method to generate an external link in
an .erb file? I have tried various options, but keep getting routing

<%= link_to 'Ruby on Rails', '', :target => '_blank' %>


Thanks Philip, that syntax had eluded me. So simple.