The Titanosaur at the AMNH View Full Caption

UPPER WEST SIDE — What weighs as much as 10 African elephants and can peek into the top floor of a five-story building?

Meet the titanosaur.

The newest dinosaur at the American Museum of Natural History — bigger than the museum's Tyrannosaurus rex and the largest on display in North America — is so long it won't fit into an exhibition room.

Visitors will find the head of this 122-foot-long dinosaur peeking out of the gallery to greet them because its neck and tail are so long it doesn't quite fit in the room.

At 70 tons, the titanosaur weighs less than the museum's blue whale. However, the whale is 30 feet shorter.

And the ancient creature is also just a teenager, scientists discovered.

"Imagine a full-grown one," said Ellen Futter, the museum's president, as she introduced the dinosaur Thursday.

The titanosaur was made by taking casts of 84 fossil bones excavated by a team of paleontologists in Patagonia in 2014 and then making 3D prints of the bones. The actual fossils are too heavy to mount, museum officials said.

Scientists found 223 bones in total around the site from six titanosaurs, which helped them put together the composite for this one.

Opening Friday to the public as part of the museum's permanent collection, the titanosaur is the museum's "newest icon," said Futter.

The most exciting moment for the team that discovered this creature's remains was digging up its eight-foot long femur, that looked like it was "the size of a living room couch," said Mike Novacek, a senior vice president at the museum.

Getting to this particular dinosaur required building a road, removing a hill and making 18 trips to the site, said Diego Pol from the Museo Paleontologico Edigio Fergulio in Trelew, Patagonia, who helped make the discovery.

Scientists believe the adolescent may have been separated from his group and died of hunger or stress.

Recently, scientists have been finding bigger and bigger dinosaurs because excavation has expanded to South America, said Mark Norell, chair of paleontology at the museum.

There may be titanosaurs to find on every continent, he said.

"There's nothing like finding a brand new fossil," said Novacek.

The titanosaur is now part of the permanent collection and is included in the price of museum admission.

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