Fox already controls National Geographic’s cable channel in two joint ventures, one for the U.S. and the other for international. Under the agreement announced this morning, the entertainment giant will pay $725 million in cash and equity to control The National Geographic Society’s other media assets — including its famous magazine.

When the deal closes — expected later this year — Fox will have a 73% stake in a new joint venture to be called National Geographic Partners. In addition to the cable channels and magazine, it will include National Geographic Studios, digital and social media platforms, books, maps, children’s media, location-based entertainment, archival sales, licensing and ecommerce.

Declan Moore, National Geographic’s Chief Media Officer, was named CEO of National Geographic Partners. The non-profit’s CEO Gary Knell, will be the first chairman. But the two companies will be equally represented on the JV’s board, and the chair will alternate annually.

“We’re working hard to focus our portfolio on brands that have unquestionable consumer appeal,” Fox CEO James Murdoch says. The new JV “creates vast opportunities and enables this business to be even more successful in a digital environment.”

Fox’s investment will double NatGeo’s endowment to about $1 billion, enabling it to increase its investments in science, research, and education.

Moore calls the expansion of the 18-year partnership with Fox “another milestone” that “ensures that we will have greater resources” for its work including grants for scientists and explorers.

“As media organizations work to meet the increasing demand for high quality storytelling across multiple platforms, it’s clear that the opportunity to grow by more closely aligning our branded content and licensing assets is the right path,” he adds. “We now will have the scale and reach to continue to fulfill our mission long into the future. The Society’s work will be the engine that feeds our content creation efforts, enabling us to share that work with even larger audiences and achieve more impact. It’s a virtuous cycle.”