Senior members of the scientific establishment are trying to persuade their juniors that they can popularize without jeopardizing their careers. But those efforts are only slowly bearing fruit. Doubts remain whether one can truly dazzle a lay audience without giving up at least some professional respectability.

The exemplar was Carl Sagan, the astronomer who became the founding father of effective popularization of science. Sagan, who died of pneumonia last December at the age of 62, was probably the best-known scientist of his era. His appearances on the Tonight Show; his Cosmos series on public television; his more than 20 books - many of them best-sellers - on subjects as diverse as astronomy and the brain; and his articles for the Sunday Parade magazine made a huge lay audience aware of the wonder and excitement of science. Even posthumously, Sagan is bringing science to the masses. The motion picture Contact, based on his 1985 book by the same name, was released earlier this month.

Yet that success led some senior members of the United States' science community to regard Sagan with suspicion. They overlooked his solid contributions to planetary astronomy. Starting at Harvard University and later as director of Cornell's Laboratory of Planetary Studies, Sagan calculated the greenhouse effect on Venus, elucidated the Martian surface, and explained the organic oceans on Titan, Saturn's largest moon. Nevertheless, many of his scientific colleagues tarred him with the pejorative term "popularizer" and criticized what they saw as his flamboyant style.

That perception resulted in the denial to Sagan of membership in the National Academy of Sciences (NAS). The academy's astronomy section nominated him for membership in 1992. But following an objection from one member, the academy's general membership failed to give him the necessary two-thirds majority vote.

Two years later, the academy appeared to repent and relent. It awarded Sagan its Public Welfare Medal for "distinguished contributions in the application of science to the public welfare." But it was hard to avoid the message that the scientific community frowned on the public popularity that came with Sagan's remarkable success in popularizing science.

Today, though, most senior scientists recognize that the field needs an articulate spokesman like Sagan to justify research funding to politicians intent on cutting all fat out of the U.S. budget. "God, we miss him," laments Robert Park, a professor of physics at the University of Maryland and communications director for the American Institute of Physics. "If only he were around to be our spokesman."

Competition for scarce federal funds is the obvious reason that the scientific establishment wants more scientists who can explain their pursuits and those of their colleagues to skeptical constituencies. "We no longer sit back and wait for people to come to us and beg us to do research," states Park. "We're competing with welfare mothers."

Not everyone in the community agrees that effective popularization of science affects research's political fortunes. "What is the evidence that public support for science is related to public understanding of science?" asks Daniel Greenberg, who takes an often acerbic view of science policy in his role as editor of Science & Government Report. "There's none."

Shirley Malcom, director of education and human resources at the American Association for the Advancement of Science, agrees. "Public support is not necessarily related to public understanding of science," she says. However, she adds, for nonscientists, "knowledge is personally empowering."

In fact, economic gain is not the only rationale for desperately seeking a new Sagan. One view is strictly pragmatic. "There's so much science that scientists can't keep up with all fields, yet science is becoming more integrated and interdisciplinary," explains Baruch Blumberg, a Nobel laureate in medicine or physiology who is spending a year at Stanford University writing a book on the scientific process. "If there's a scientist who combines objectivity with excitement, that's very valuable."

When they try to understand a piece of scientific work, adds Nature editor Philip Campbell, "scientists outside any discipline need just as much translation as anyone else."

There's also the more altruistic rationale for explaining science to a nonspecialist audience. The people who ultimately fund basic research with their tax dollars "have the right to know what they have bought," says Malcom.

Another obvious constituency for science exposition consists of individuals actually affected by the subject's potential - individuals with illnesses and their families, for example, and those affected by environmental problems. "When science actually touches on people's lives," says Campbell, "it's self-evident that it must be accessible."

Bassam Shakhashiri, a professor of chemistry at the University of Wisconsin, Madison, who was assistant director for science education at the National Science Foundation between 1984 and 1990, puts the argument more strongly. "The scientific community has an obligation to our fellow human beings to share the joy of doing science," he states. "We need to reflect our value system to the public at large."

Evidence is emerging that the need to communicate science to nonscientists is getting through to senior levels of the scientific establishment. In recent weeks NAS president Bruce Alberts has spoken out strongly in favor of efforts to present science to the general public in approachable ways. "For scientists to be more influential at home and abroad, it also is important that we work to enhance our connections to the rest of society," Alberts said at NAS's annual meeting in late April. "Through such connections, we can give our fellow citizens a much better understanding of science and its values. We can also spread our values more widely."

"When you get comments like that, it helps a lot with those segments of the community who have not, in the past, valued this as a serious ability for scientists," observes Malcom.

The enthusiasm seems to be percolating through the community. "I see a much more flexible world out there for scientists to popularize," says Sharon Dunwoody, a journalism professor at the University of Wisconsin, Madison, who specializes in science and the media. As she sees it, the scientific culture is becoming much more savvy about the value of publicity. "In the 1970s, scientists viewed media skill as equivalent to advertising," she declares. "Now they view it as good advertising."

"It seems to me that scientists are more open to getting media coverage for themselves and more aware of the benefits that can accrue to them personally and, ultimately, to the scientific endeavor in general," comments David Salisbury, who oversees media coverage of science at Stanford University.

Leon Lederman, a Nobel laureate in physics and former director of the Fermi National Accelerator Laboratory, puts the point slightly differently. "Marketing is considered to be undignified," he says. "But who can do it for science apart from scientists?"

To market science, many scientists must overcome "a feeling that promoting science is self-serving," says Mary Woolley, president and CEO of Research!America, an Alexandria, Virginia, advocacy organization. Research!America, she says, "thinks of scientists as the best spokespeople for science."

In fact, a lot of scientists are beginning to use the media as a marketing tool. Scientists realize that their professional colleagues will notice their work when it is featured in prestigious publications such as the New York Times. Indeed, according to Nature's Campbell, some preliminary evidence suggests that scientific papers that receive media coverage also receive more citations in the later literature.

Questions about the validity of popularizing science do not apply evenly to the entire scientific community. Many top-notch scientists have willingly discussed their own field and others for the benefit of lay audiences. Physics Nobel laureate Steven Weinberg of the University of Texas, for example, has written successful lay-level books on the nature of the early universe. Titles include Dreams of a Final Theory (New York, Pantheon Books, 1992) and The First Three Minutes: A Modern View of the Origin of the Universe (New York, Basic Books, 1997). "It's very acceptable because he's doing real physics at the same time," says Maryland physicist Park.

A Nobel Prize helps to remove any taint of scientific shallowness. The late Richard Feynman; Lederman; new California Institute of Technology president David Baltimore, and biologist Philip Sharp of the Massachusetts Institute of Technology have all communicated successfully with the world beyond the lab via books, popular lectures, and work with local schools. British cosmologist Stephen Hawking and evolutionary biologist Stephen Jay Gould of Harvard earned reputations for effective popular writing in books and articles, after each had established impeccable scientific credentials.

One scientist/popularizer who made his mark with the public while still establishing a reputation in the laboratory is Oxford University zoologist Richard Dawkins, author of The Selfish Gene (New York, Oxford University Press, 1977) and other books. "Dawkins is for biologists what Sagan was for physical scientists," says Park. "What sets him apart is that The Selfish Gene was both a popular account and contained a fundamental new way of looking at evolution." Fellow physicist Lederman agrees: "I think Dawkins is very good."

Interestingly, life scientists take a slightly cooler view of Dawkins. "He's a zealot, so to speak, dedicated to the notion of evolution," says Blumberg. "There's a danger in that." But he also recalls that Dawkins "drew the biggest crowd we had" when he spoke to Blumberg's students at Oxford University, where Blumberg was master of Balliol College until 1995.

Other life scientists are less charitable. "Even today Dawkins is resented by a number of biologists," reports Park, although Dawkins himself insists that "I do not feel I have suffered that way." Certainly, petty jealousies of colleagues who appear in the media have not disappeared. One scientist at an English college "was made to feel very unpopular" because of his ability to connect with the public, recalls Campbell.

Why such resentment? Critics not only are jealous of the fame and fortune that good popularization can bring, but also envy the ability of good communicators "to take complex issues and explain them in a simple way," says Shakhashiri.

Even a redesign of Nature, intended to attract more readers by making the journal more understandable to scientists beyond the narrow specialties of particular papers, drew criticism. David Jones, a physical chemist at the University of Newcastle-upon-Tyne, commented that the redesign made Nature "more dramatic to look at but harder to read." Ironically, Jones is a highly successful popularizer. Under the pseudonym Daedalus, he writes a weekly column of satirical speculation for Nature.

Senior academics aren't the only individuals erecting barriers to good science popularization. So far, the television networks have resisted science-based series. With seed money from the National Science Foundation and the Department of Energy, Lederman has spent two years trying to persuade television executives to run L.A. Science, a show that would focus on scientists in much the same way that L.A. Law and E.R. have put the spotlight on lawyers and doctors. "Producing a television show is not difficult," comments Lederman. "The difficulty is getting somebody to point a camera in your direction." Ever skeptical, though, Greenberg's Science & Government Report has described Lederman's efforts as "a comedy in its own right."

Blumberg, meanwhile, appeared in Plagues, a well-received show put out over the public television network by Philadelphia station WHYY 10 years ago. But his plans for a series were scratched when the station spent its entire $500,000 budget on the single show.

What, then, should young scientists do when they want to popularize science? "If they want to accomplish serious scientific work and popularize, [they should] be ready for some sacrifice," advises Malcom. "They may want to establish their scientific credentials first."

One consolation is that help is available for would-be popularizers. "At Research!America, we try to provide tools for scientists ready to move out into the community," says Woolley. These include speakers' kits that provide scientists with instructions on how to deal with a variety of audiences, from school groups to the international media replete with television and flash cameras.

Woolley emphasizes that scientists should not feel that they must run the gamut of public presentation. "One size does not fit all," she says. "We need to have various levels of public outreach where everybody can feel comfortable; we provide the motivation to help them become comfortable."