According to the first amendment to our U.S. Constitution-
Congress shall make no law respecting, an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
Therefore those Americans who wish to practice their religion for all to see and hear, may have a communion service, even on the moon. Here is a blog telling about Buzz Aldrin's communion service on the moon. Above is a clip from the 1998 HBO special.