The final voyage of the U.S. space shuttle Atlantis is the most popular topic among Facebook users, who are collectively posting about the launch countdown several times per second.

A great deal of these postings express nostalgia about the end of an era for U.S. space exploration, along with remarks about various delays in the timing of the launch.

Many of the posters are sharing links to live news coverage of the event, along with the official U.S. National Aeronautics and Space Administration website.

Readers, what are your friends posting about the Atlantis?