NASA plans five more space shuttle missions this year, the first in early February, and then the historic shuttle program will come to an end.

But just 40% of Americans believe the space shuttle program has been worth the expense to taxpayers, according to a new Rasmussen Reports national telephone survey. Nearly as many (36%) disagree and say the program has not been worth the expense. Another 24% aren’t sure.

Still, 64% of adult say it is at least somewhat important for the United States to have a manned space program. That number includes 26% who say it’s very important. For 30%, however, a manned space program is not very or not at all important.

Support is down 12 points from last May, though, when 76% said it was important for the United States to have a manned space program. That support had held steady from a survey two years earlier.

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In fact, 50% of Americans now say the United States should cut back on space exploration given the current state of the economy.

Yet 60% also say it is important for the United States to have a space program that relies upon unmanned research spaceships, including 20% who feel it is very important. Thirty-one percent (31%) say a research program with unmanned spaceships is not very or not at all important.

Americans have mixed feelings about the overall space effort. Last July, only 45% said that the U.S. investment in space exploration since Americans first landed on the moon has been worth the expense. Thirty-five percent (35%) disagreed and felt the space effort was not worth the money spent on it.

A plurality (46%) of men say the space shuttle program has been worth the expense. Women are more closely divided on the question. Adults ages 30 to 49 are the most supportive of the shuttle.

Investors are more likely than non-investors believe the shuttle program has been worth the expense.

Republicans and adults not affiliated with either major political party are more supportive of the shuttle program than Democrats are.

Similarly, men believe more strongly than women in the need for both manned and unmanned space programs.

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