National Museum of Natural History building exterior. (Smithsonian Institution/Smithsonian Institution)

Kirk Johnson, chief curator and vice president of research and collections at the Denver Museum of Nature and Science, has been chosen by the Smithsonian Institution to head the National Museum of Natural History.

Johnson, 51, helps manage a $40 million annual budget at the Denver museum, which receives 1.4 million visitors per year. He oversees a 70-person research and collections division and is responsible for the museum’s two dozen collections. In late 2010, Johnson, who specializes in fossil plants and geology, led a nine-month excavation in Snowmass Village, Colo., that uncovered thousands of Ice Age bones. He has written a number of books, including “Cruisin’ the Fossil Freeway,” which became the basis for a traveling museum exhibit.

“Kirk brings an established national and international reputation as a top scientist, educator and museum administrator to the National Museum of Natural History,” said Wayne Clough, secretary of the Smithsonian. “He is a perfect match to lead the museum — among the very best in the world — into the next decade.”

Reached by phone in Denver, where he was coming from a tearful goodbye to his staff, Johnson said: “Can you imagine a more fun challenge? I’m going to dive into that place and know it backwards and forward.”

Johnson arrived at the Denver museum in 1981 and for the first five years was the lead scientist for the “Prehistoric Journey” exhibit. “I’m fascinated in how you take the history of life on our planet and exhibit it in a museum context,” he said.

Kirk Johnson, chief curator and vice president of research and collections at the Denver Museum of Nature & Science, has been appointed the Director of the National Museum of Natural History. (Forrest Gibson/Denver Museum of Nature & Science)

Johnson said he’s like a kid on Twitter and Facebook, and he looks forward to drawing younger visitors. “I’m a blue-sky kind of guy, and there are so many things you can do with a natural history museum.”

Eva J. Pell, the museum’s undersecretary for science, who chaired the selection committee, said a major goal is to reach beyond the museum’s approximately 7 million visitors a year and engage those who are interested in natural history but can’t make it to the museum.

“Kirk Johnson has extensive experience in research, in working with collections, he’s got enthusiasm, and enormous capacity in the use of social media which I think is going to be critical for the next leap forward for natural history,” Pell said.

Johnson’s first big project at the Natural History Museum “is going to be the dinosaur hall, which is going to undergo a complete re-creation,” Pell said. “He’s going to have an opportunity to really put a new face on that exhibit and add many new features in terms of interactiveness. It’s one of the big opportunities to show what he can do in moving this museum forward.”

The Natural History Museum is one of the Smithsonian Institution’s most popular museums, and it has an annual budget of $98.8 million.

Johnson, who will begin Oct. 29, replaces director Cristian Samper, who leaves Tuesday after nine years with the museum to become president and chief executive of the Wildlife Conservation Society in New York.