If you happen to see aliens riding the monorail in Las Vegas this month, don't be alarmed: They come in peace.

Through December 22, Klingons, Romulans, and Ferengis will ride the monorail Monday through Friday from 9:30 a.m. to 10:30 a.m. and from 4:30 p.m. to 5:30 p.m. to “conduct research” on what they believe is “the most technologically advanced public transit system in the Milky Way galaxy.” Even better than the Enterprise?

Actually, the “aliens” are riding the rails to promote Star Trek: The Experience, the Las Vegas Hilton's new attraction that takes guests on an interactive voyage to the 24th century. The monorail car they are riding has been decked out in a futuristic theme as imagined by designers of the attraction in conjunction with the Las Vegas Monorail Co. The monorail traverses the Strip with stops at the major casinos.

Earthlings are encouraged to interact with the aliens.