So what is actually sitting up there on the very tip of Cornell University's McGraw Tower? Is it a putrefied pumpkin, or is it a pulp fiction?

To find out if upstate New York's most famous gourd is fruit or fake, Cornell undergraduate students are being challenged to enter the great pumpkin contest, open to individuals or teams. The only rules: no flying or climbing, and all feet must stay firmly on the ground.

"Anything else is fair game," says Mary Sansalone, a Cornell civil engineering professor who is one of the three organizers of the competition.

The pumpkin contest came to fruition in the fertile brain of Provost Don Randel, who concluded that if Cornell ingenuity could place a pumpkin on top of a 173-foot tower (it was first noticed on Oct. 8), then surely rational Cornellians could observe, analyze and draw conclusions about the pumpkin's reality from the ground

"It's been up there so long that people are beginning to doubt that it's real," says Sansalone.

This view is endorsed by Cornell professor of fruit and vegetable science Chris Wien. "This is not a real pumpkin," he states. "With the amount of rain we have had over the past four months, the structural integrity of a real pumpkin would have collapsed long ago."

At first, the "pumpkin," which appears to be speared on the lightning rod at the apex of the 125-year-old bell tower, was thought to be a genuine, 60-pound botanical, and university officials decided to let it simply rot away. But that hasn't happened, and the still bright-orange gourd remains defiantly in place.

Randel insists that students must use their intellectual abilities rather than mountaineering or flying skills to analyze the pumpkin. That would veto ideas of man-powered blimps or helicopters hovering above McGraw Tower and retrieving a pumpkin sample with a long probe. But it wouldn't rule out a radio-controlled device.

How, though, to verify the solutions to the competition? Hal Craft, Cornell vice president of facilities and campus services, has assured the competition's organizers, who also include civil engineering instructor Benjamin Schafer and assistant civil engineering professor Linda Nozick, that he will obtain a pumpkin sample over the spring break. Handily, a crane is being used during masonry repairs to the tower.

Sansalone expects that Cornell ingenuity will produce several correct answers. In that case the judges will, she says, look for the most creative and inventive techniques used in obtaining solutions. "We don't want to give the students any ideas," says Sansalone. "But there are at least a dozen different approaches one could use to solve this problem."

If the contest turns into the pumpkin equivalent of Olympian 9.5, 9.2 and 9.3 scoring, it will be in expert hands. The judges will be Randel and professors Robert Richardson (a Nobel Prize winner), and Persis Drell (physics), Yervant Terzian (astronomy), Rita Calvo (genetics), Dan Huttenlocher (computer science), John Kingsbury (plant science) and dean emeritus William Streett (engineering).

The prize? Mainly it will be recognition from peers, possibly to equal the awe with which the original -- still anonymous -- intrepid pumpkin placers are regarded. But there also will be a signed copy of Charles Schulz's cartoon, "The Great Pumpkin," and a semester's-worth of books (or a $250 gift certificate for graduating seniors). All top-scoring entrants will receive a pumpkin T-shirt.

All participating Cornell undergraduates have a March 13 deadline by which to submit a short report to the provost's office at 300 Day Hall, including: the names, addresses and affiliations of the participants; the techniques used to analyze the pumpkin; a photograph of the equipment or of the technique used, and, finally, the conclusions.

"This is a serious project," says Sansalone. "But we also want to have a lot of fun with this competition." She and Schafer and Nozick can be contacted about the rules in civil and environmental engineering, Hollister Hall.

The pumpkin can be viewed live, by computer, on the University's "pumpkin cam" at the web site http://pumpkin.library.cornell.edu.