The planetarium features the highest resolution virtual reality simulator ever built. The simulator combines state-of-the-art graphics computers, a 3-D map of the galaxy, a communications network and CRT projectors to create the illusion of traveling past planets, galaxies and nebulae.

Audio speakers and subtle motions in the darkened planetarium's theater seats simulate blast-off from Earth, as well as movement towards and away from large heavenly bodies. A trip through a black hole is a high point of the virtual journey.

The creation of this experience did not come cheap or easy. The American Museum of Natural History spent three years and $210 million on the 335,500-square-foot addition to its facilities. The Rose Center for Earth and Space doubles as a museum and as a research facility. The Center's eight-member astrophysics department works under astrophysicist Neil de Grasse Tyson, director of the Hayden Planetarium.

Under the Digital Dome

The star of the museum's new addition is the Hayden Planetarium's Digital Dome system, a theater and the largest scientific visualization instrument in the world, able to display data sets in 3D.

Aram Friedman, chief engineer on the team that created the Digital Dome, called it the "single greatest project" he's worked on, ahead of such high-profile projects as the flight simulator at the Luxor Hotel and Casino in Las Vegas.

Friedman and his 16-member team spent thousands of work-hours over more than two years writing code to tie together the $17 million imaging hardware, software, network and theater display system for the planetarium's 21-meter dome. They coordinated the work of hardware and software vendors, wrote specs and tested the system while serving as intermediaries for the project's artists, scientists, software developers and producers.

"We're the only ones who look at it as a grand machine," said Friedman. "We had to tie together all the tools and orchestrate them to create a story and automate everything in the Digital Dome."

Friedman's work on the Digital Dome began two years ago when he was hired by the museum to read responses to its request for proposals for a planetarium dome. "The museum needed someone to understand the technology and evaluate whether companies could deliver what they promised," he said.

Break with tradition

Though the museum originally set out to build a traditional planetarium, Friedman said key individuals, including Dennis Davidson, now director of the museum's Digital Galaxy project, convinced the museum to follow a different path.

"It was Davidson's lofty ideas about what could be done that kept us focused," Friedman said.

In 1988, Davidson, then an astronomical artist at the museum, met with the noted astronomer Carl Sagan and visited an architectural design studio in New York, where the two saw a 3-D model of the universe, including intricate small galaxies made of fiber optics. Davidson said that model inspired him to create a similar model on the big screen for the new planetarium. "I wanted to create a very different kind of planetarium, one that was based on an instrument for visualizing scientific data of all types," Davidson said. "I imagined an immersive space that could show how molecules fit together."

Davidson's idea was supported by the museum's president, Ellen V. Futter, who was anxious to revive parts of the museum that needed sprucing up. The old Hayden Planetarium, built in 1935, had also lost many of its astronomers.

The museum's Digital Galaxy project grew out of a grant from the National Aeronautics and Space Administration (NASA) to map the galaxy with a level of realism. "The idea was to create something that met cinema standards, but also had a high level of scientific accuracy that could bring the scientific data to the peer level of universities," Davidson said.

The museum wanted to be able to present data for both science and entertainment purposes, Davidson said. He envisions scientists using the system to image and display DNA molecules in the human genome.

The Digital Dome's hardware includes seven CRT projectors able to display video, and an Onyx2 Infinite Reality2 System from Silicon Graphics Inc. (Mountain View, Calif.), with seven graphics pipelines and 28 R12000 300-MHz processors. Onyx2 compiles data and renders graphics in real-time. A network sends the images to the dome's projectors and a 14-terabyte system of RAID storage records the presentations.

A Mark IX Star Projector from Carl Zeiss Corp. (Oberkochen, Germany), a planetarium staple, provides the earthbound view of 12,000 stars in the night sky during the planetarium show. As visitors are moved away from earth, the show switches to digital video created by the Onyx 2, which calculates a location and renders every star and nebula 30 times a second, projecting approximately 9 million pixels in real-time.

The planetarium's renderings are based on data from NASA, the the Hubble Space Telescope and the European Space Agency's Hipparcos database.

Reporting from space

While the museum focuses considerable attention on the planetarium's sky show, "that represents only about 50 percent of what the Digital Dome can do," Friedman said. The Dome is also able to show live high-definition images from NASA's Space Shuttle, for example.

The engineers' contract with the museum runs out in June. Friedman said he and the projects other engineers might stay if the museum offers other challenging projects. Otherwise, they may take their experience on the road to other planetariums.