NEW YORK — Overall public support for NASA’s plan to complete the international space station (ISS), retire its shuttle fleet by decade’s end and move on to the Moon and Mars remains strong, according to a new Gallup Poll, though at least one other recent survey shows the program is less popular with people aged 18-25.

A Gallup poll released Sept. 25, the last of a three-part series of surveys sponsored by the Coalition for Space Exploration, a space industry group founded in 2004 to promote human exploration of space, found that about two-thirds of Americans polled in the survey support NASA’s approach to return astronauts to the Moon, provided the effort’s cost does not exceed more than 1 percent of the federal budget.

Respondents were presented, for example, with the following statement and question: “In January 2004, a new plan for space exploration was announced. The plan includes a stepping-stone approach to return the space shuttle to flight, complete assembly of the space station, build a replacement for the shuttle, go back to the Moon, and travel to Mars and beyond. If NASA’s budget did not exceed one percent of the federal budget, to what extent would you support or oppose this new plan for space exploration?”

Of the 1,000 people surveyed 19 percent said they strongly supported the plan and 47 percent said they supported it.

Similarly, respondents were told and asked: “NASA’s budget request this year is under one percent of the federal budget, which would amount to approximately $58 per year for the average citizen. Do you think the nation should continue to fund space exploration?” Thirty-two percent said they favored funding NASA at the current level, 22 percent favored a slight increase and 9 percent favored a significant increase.

NASA’s 2006 budget of $16.6 billion is about 0.6 percent of the total 2006 federal budget of $2.7 trillion.

The White House budget request for NASA, which is still pending before Congress, seeks about $16.8 billion in 2007 — a 1 percent increase over 2006 — and represents a cost of about $58 per year for the average taxpayer, coalition officials said.

Jeff Carr, chairman of the Coalition of Space Exploration, said the coalition deliberately asked Gallup to determine the level of support people would have for the space program after telling them how large the budget is as a percentage of the total U.S. budget.

“What we’re finding is that, simply given the information the public response is extremely favorable — and that’s a terrific sign for the vision,” said Carr, who is also director of communications and public relations for United Space Alliance, a joint venture of Boeing and Lockheed Martin that operates the space shuttle fleet for NASA.

The Princeton, N.J.-based Gallup Organization conducted the new poll between Aug. 2 and Aug. 19 in a telephone survey of adults age 18 or older. Similar surveys were conducted in March 2006 and June 2005 with similar overall results.

Carr said one reason for presenting respondents with facts followed by a question was numerous polls in recent years that revealed widespread public misperception about the actual size of NASA’s budget and its percentage of overall U.S. government spending.

In addition to the three Gallup polls, the Coalition also commissioned four focus groups which were conducted in July by The Everett Group of Gambrills, Md., in Atlanta, Boston, Dallas and Portland, Ore. While those focus groups did not represent a statistically valid sample of the overall population, they were used to help the coalition “drill down” on what might be behind the answers to some of the key questions that had appeared in the first two Gallup surveys, according to The Everett Group’s executive summary of the focus group effort.

One thing they did was reinforce the polling data that had shown misperception about the budget.

“Very few group members, across markets, understood how much money NASA receives from the federal budget (while some underestimated the amount, even more overestimated). Guesses for 2006 federal funding ranged from $1.5 million to $100 trillion,” the Everett Group wrote in its executive summary about the four focus groups.

When NASA’s budget was presented to the focus groups in terms of its percentage of the overall federal budget, the Everett Group found that it “prompts some to say it’s a surprisingly small piece, while others ask what we’re spending all that other money on.”

The focus groups also showed that younger Americans are more skeptical about the vision than older generations. ” Portland youth seemed especially jaded about President Bush’s credibility — mention of his ‘vision for space’ elicited questions of how he personally would profit from it, what his motivation was for pursuing [it]. Also Mars generated more interest than going back to the Moon,” the executive summary said.

A survey presented by Denver-based Dittmar Associates during the American Institute of Aeronautics and Astronautics Space 2006 conference Sept. 19-21 in San Jose, Calif., concluded that young American adults 18-25 “are largely disinterested” in the Vision for Space Exploration announced by President Bush in January 2004.

Those results came from a follow-up to Dittmar’s 2004 “Market Study for Space Exploration.”

While t he overall results of the 2004 Dittmar survey were similar to the three Gallup surveys’ findings, Dittmar found that 65 percent of those surveyed responded positively when asked if they were interested and excited about the near-term aspects of the vision leading up to a return to the Moon.