Carl Sagan, star of stage, screen and space probe and professor of astronomy at Cornell University, introduced himself and his "Cosmos" to the world last night at the National Academy of Sciences.

In opening remarks, before the premier screening of "Cosmos," the $9-million, 13-week epic that the Corporation for Public Broadcasting hopes will be its season-block-buster, CPB's Cal Watson called Sagan the man "who's done more to make space understood than any other person who has ever lived." Forget Galileo and Copernicus. It was a classic case of opening night hyperbole, erring on the side of whoever happened to be present.

Sagan himself -- the 45-year-old author of the pop-science tomes "the Dragons of Eden" and "Broca's Brian" and project-coordinator for the Pioneer and Voyager space probes, said he hoped the series would "appeal not just to the mind, but also to the heart." He spoke of the growing popularity of science among Americans.

"Every second Tuesday," he said, "there's a new science magazine published" -- usually, he mght have added, with a story by or about Carl Sagan.

The one-hour episode screened last night starts with Sagan declaring "the comos is all that is or ever was, or ever will be." He blows a dandelion seed into the coastal breezes in Monterey, Calif., and the camera follows the seed off into the universe, with Sagan running in hot pursuit in a spaceship that looks borrowed from "Star Trek." For 20 minutes the audience roars through galaxies, pulsars and quarks, ever dazzled by Close Encounters of the Sagan kind.

When a closer view of a particular phenomenon is called for, Sagan opens a trapdoor on the ship to allow viewers to peer down.

And at one point in last night's screening, one of the 400 guests -- a scientist by trade -- puckishly observed, "I wish he'd fall through the trapdoor."

Reaction to the screening was mixed. And after such lofty travel there was a quick dash to the earthly spirits.

One woman approached Sagan and told him that his "Cosmos" would be up against "CHiPs" and "Charlie's Angels."

"I've never seen them," the scientist replied, "so I don't really know what that means."

Sagan chatted with general well-wishers, and those awe-struck by the astronomer-turned-celebrity. He joked with some of his scientific colleagues, including Richard Berendzen, the new president of American University, perhaps the only astronomer in the United States to hold such a post; Paul MacLean, a pioneer in brain research, and Herbert Friedman, who has done advanced research in X-ray and ultraviolet studies at the Naval Research Laboratory.

"Science," said Sagan, "is fun. And if kids get the idea from this show that science is okay, I think maybe they'll consider being scientists."