Goddard Space Flight Center scientists trying to unlock secrets of the universe have had clues to the prehistoric past resting literally beneath their feet.

Dinosaur tracker Ray Stanford this summer discovered on the center's campus the apparent footprint of a nodosaur, a plant-eater that roamed suburban Washington, D.C., about 110 million years ago.

The track, almost 14 inches wide, is near a sidewalk at the Goddard complex in Greenbelt, Maryland, home to 7,000 employees engaged in astrophysics, heliophysics and planetary science.

"It is sheer poetry," Stanford said on Tuesday. "It is because of the juxtaposition that evokes so much interest."

Stanford late last week gave NASA officials a firsthand look at the print, which was hiding in plain sight all these years.

"It's something that if you knew what you were looking for you would have seen," said Alan Binstock, in charge of cultural and archaeological matters at the facility. "That's what's so amazing."

A paleontologist will do a survey to confirm the find, Binstock said, and will help determine what areas on the fenced campus may need further protection.

"I said this is not the only one," Stanford said. "There has to be many here."

Officials are staying mum on the footprint's exact location.

Stanford, who says he has found about 1,000 dinosaur tracks over the years, said he and a Johns Hopkins University expert are convinced it is an authentic find.

The nodosaur, which hails from the Early Cretaceous period, is named for the bony nodes found on its head, shoulders and body edges.

"They were basically an armored tank with relatively short legs," said Stanford. "They had plates reminiscent of what you would see on the crocodile."

The nodosaur, perhaps 15 feet long from snout to tail, left a print of its right rear foot in thick mud.

"You see the back of the foot, what we call a heel, is lifted up," Stanford said. "It was moving as fast as one of these guys could go. I suggest it was running."

Stanford, 74, of College Park, Maryland, moved to the area in 1986, shortly after he retired in Texas from a nonprofit research group.

In 1994, he and his children found the footprint of an Iguanodon dinosaur near the College Park airport.

"I spotted this thing and I called them over," Stanford said. "I asked 'what does it look like?' In one voice, they said, 'It looks like a dinosaur track.'"

Stanford has since worked with professionals and academics. In September 2011, he co-authored a Journal of Paleontology paper on a new nodosaur species.

Stanford often has lunch with his wife, who works at Goddard.

Several years ago, while driving there, he noticed material he thought might be indicative of the Cretaceous period.

In June, after having lunch at Goddard, Stanford returned to an area where he had found the 3-inch track of a theropod.

He came upon the nodosaur track.

Goddard's Binstock gave his own description of the discovery.

"If someone said, 'What's that?' I would have said an elephant that needs a manicure."

News of the discovery has swept the Goddard campus in recent days.

"Everybody's excited about it," Binstock said. "We're all about discovering new things."