These words are painted on Arnold's car as a kind of motto. Connie doesn't know what they mean but recognizes them as slang or a catchphrase that had been popular with teens "the year before" but that had gone out of fashion.

The phrase makes no sense, and the story gives no indication of how it had been used when it was something people said. Grammatically, it is a little ambiguous: the word man can function as a verb, in which case the phrase is a kind of command for people to "man" the flying saucers (e.g., get in them and be ready to fly them). Or is can be an exclamation (if one supplies some missing punctuation), as in, "Man! The flying saucers!" In this case, the phrase has an ironic quality, calling attention to the "flying saucers," perhaps as a reference to the general craziness of life, which perhaps can be blamed on flying saucers and aliens in general.

Either explanation makes little sense. What is significant about the phrase, however, is that it is a little "off," as if Arnold had been up on the latest slang enough to have it painted on his car (another reference to his age and difference from kids like Connie). It is another piece of evidence that there is something not quite right about Arnold.

Closer inspection of the phrase reveals that it also functions as an anagram. If you rearrange the letters, you can spell out "He Satan Lucifer" (with a few leftover letters). In this sense, the phrase functions as a kind of clue to Arnold's true identity, as many readers draw parallels between Arnold and the devil or believe he is the devil himself.