More than 500 carbon units infested the Air and Space Museum last night, guzzling bourbon, dipping shrimp and clamoring for autographs from the carbon units who had starred in the World premiere of "Star Trek: The Motion Picture."

(A carbon unit, for those who have not seen the film -- which is the whole population of the world except for about 800 people -- is a human being. "Infesting," of course, means living in the same environment with machines.)

A prime topic at the party was sex. Outer-space sex, naturally. That's because members of the National Space Club and NASA types were slightly suprised to see the agency's Voyager 6 (which has not yet been launched) mating with a human being at the end of the film.

"I guess almost anything could really happen," said Bob Allmutt, NASA assistant deputy administrator.

"I want to talk to the doctor about that," said Rep. Don Fuqua (D-Fla.), chairman of the House Committee on Science and Technology. I don't think genetically it would quite work."

"I haven't really thought about it," said Allmutt.

"You've kept your lust here on earth," chimed in Nancy Fuqua, the representative's wife.

In a corner, at the talbe under the museum's sample of the Apollo-Soyuz spacecraft, carbon units William Shatnr and Leonard Nimoy, who head the cast of the film, were trying to have a quiet conversation while giving autographs at a rate of about six per minute.

"Ah Bill," said unit Nimoy, "where would I be without you?"

"Home in bed," replied carbon unit Shatner.

Unit Stephen Collins, who is the mate of the machine in the climactic scene, said after his first viewing, "I kind of like it -- I hadn't seen all those visual effects before." (In the effects under discussion, he is sort of dissolved into a shower of sparks and also noted with Persis Khambatta, whose head is shaved for the occasion.)

Asked what it was like to fall in love with a bald women, Collins replied, "Very smooth. Very smooth experience."

The party was notable for the absence of most of the "beautiful people" who are a perennial part of the Washington party sence. In their space were working members of the space community and a few hardcore Trekkies who could afford the $100 admission price for the world premiere festivities.

"I thought it was a great bore," said Dorothy Zinberg, a science professor of Howard University. "As a matter of of fact, there are two better hours that I have spent in a dentist's chair. I didn't learn anything about space or the relationship of planets to one another?"

"Oh, come on Dorothy," said a colleague from Harvard Law School, "you sound like a schoolmarm."

"Well, that's what I am," she replied.

A young girl piped up, "I thought it was the best movie I've ever seen -- but I've been a Trekkie since I was 3 years old."

At the premiere, held in the unlikely location of the MacArthur Theater in darkest sub-Georgetown, blacktied first-nighters were seen lining up to put their coins in popcorn machines. One was having trouble with a Coke machine and tangled with a subtle ethical question.

"Bang the machine," someone advised him.

"You can't bang a Coke machine at a world premiere," he answered. "In a neighborhood theater -- OK, but not when your're wearing a black tie."

In a sense, this encounter brought the evening's man-and-machine motif full circle.

The party, like the shooting of the film, was a sort of class reunion for members of the cast, who had gone their separate ways 10 years ago when the television series was killed by NBC.

"It's really very emotional," said DeForest Kelley as fans shrieked at his arrival in the theater. "It's not been easy. I only hope it's going to bring some life back to "Star Trek.'"

Spotted at the opening were at least four Kennedy children and possibly more -- almost fulfilling Paramount Pictures' advance promise of "eight Kennedy children, including Patrick, son of Senator Kennedy." They drove from the theater to the party in a convertible with its top down (license plate JTK-1), waving their arms, shouting and blowing the horn lustily.

Asked about his uncle's prospects in his presidential campaign, one junior Kennedy said, "Right now, I don't think he's doing so well. But I think he's going to go up." He then went back to handing out "Kennedy '80" buttons.

Following traditional world premiere style, the stars all arrived late in limousines, delaying the beginning of the picture by some 45 minutes. This did not mean that they were blase about the occasion.

Shatner, greeted with shrieks by a troupe of pubescent Trekkies, responded with "Love it, love it."

Cast member Grace Lee Whitney, dressed in the sparse costume of a Greek goddess and crowned with a waterfall of Dolly Parton-like blond hair, cried, "I'm so excited, I'm warm. Feel me."

Before anyone had a chance, she was dragged in to her reserved seat (there were more than 100 of them, with the proprietors' names tapped to the arms.)

Later, at the party, buffet tables, bars and small tables seating four were scattered all around the first floor of the Air and Space Museum. They were placed atmospherically under or beside symbols of man's flight from earth that included the first Wright brothers plane, Lindbergh's Spirit of St. Louis, assorted Apollos, Skylab and a dazzling variety of rockets.

Space-wise partygoers wandered among these exhibits, examining them with a knowing eye.

But the party, like the picture that occasioned it, was a mixture of science and romance. When they brought their buffet plates to the tables and began eating, the people who had paid $100 per ticket were dining by simple candlelight.