The
dinosaur footprints were encased in a field jacket, which is much like a
cast that a doctor would place on a broken arm or leg. This field
jacket consisted of many layers of burlap soaked in plaster, with metal
pipes added to act like splints / NASA/GSFC/Rebecca Roth
A chunk of stone bearing dinosaur footprints has been carefully
lifted from the grounds of NASA's Goddard Space Flight Center in
Greenbelt, Md., scientists report.
The dino tracks,
thought to have been left by three separate beasts more than 100
million years ago, were discovered by amateur paleontologist Ray
Stanford in August 2012.
The feature that first caught Stanford's eye was a dinner-plate-sized footprint of a nodosaur, a tanklike dinosaur
studded with bony protuberances that roamed the area about 110 million
years ago during the Cretaceous period (the period from 145 million to
65 million years ago that was the end of the Mesozoic Era). This
particular lumbering leaf-eater must have been moving quickly across the
prehistoric mud, as its heel did not sink deeply into the ground.
A closer look at the site revealed two more prints. Stephen Godfrey, a
paleontology curator at the Calvert Marine Museum, who was contracted to
preserve the find, said he suspects one was left by an ornithopod,
possibly from the iguanodontid family, which were large vegetarian dinosaurs
with birdlike, three-toed feet that walked on its hind legs. Another
smaller footprint found superimposed over the nodosaur track is thought
to be from a baby nodosaur, perhaps trying to catch up to its parent,
according to a statement from NASA.
The stretch of ground containing the prints measured about 7 feet long
and 3 feet across at its widest point. After making a silicon-rubber
cast of the dino tracks, the team covered the find in plaster-soaked
burlap, much like an orthopedic cast, to reinforce the slab and protect
it from damage during the big move. Altogether, the stone slab, the
protective jacket and surrounding soil weighed about 3,000 pounds, and
it was successfully pulled out of the ground last month.
For now, the prints are being stored at Goddard until further
scientific study is possible. The wonder of the discovery has not been
lost on space scientists at Goddard, who often find themselves studying
starlight as old as the dinosaurs.
"One of the amazing aspects
of this find is that some of the starlight now seen in the night sky by
astronomers was created in far-distant galaxies when these dinosaurs
were walking on mud flats in Cretaceous Maryland where Goddard is now
located," Jim Garvin, Goddard's chief scientist, said in a statement.
"That starlight (from within the Virgo Supercluster) is only now
reaching Earth after having traveled through deep space for 100 million
years."
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