A beam of light takes 30,000 years to get from the Earth to the center of the Milky Way, but somehow you make the journey in two and a half minutes. A million stars stream past on your way into the core. And when you arrive, you fall into infinite blackness.
Dozens of astrophysicists and computer scientists on Monday will present a computer-animated travelogue unlike any other.
The Unfolding Universe -- an hour-long documentary to be shown on The Discovery Channel (9 p.m. EDT) -- tells the story of a spinning disc of a hundred-billion suns orbiting a globe of stars and stellar remnants with a gigantic black hole in the center.
Seen from above, the Milky Way is an unremarkable spiral galaxy dotting intergalactic space. And yet, for all its blandness, its story is both familiar to scientists and emblematic of the universe as a whole.
"It's a good way to get a snapshot in the course of an hour of the breadth of cosmic history," said Tom Lucas, director of the program.
Using both the latest astrophysical simulations and computer visualization techniques, Universe showcases 20 minutes of footage that stems from months of supercomputer time at research centers such as the University of Illinois' National Center for Supercomputing Applications, the Department of Energy's National Energy Research Scientific Computing Center and Germany's Max Planck Institut fuer Gravitationsphysik.
The 29,413 frames represent the culmination of years' worth of work.
Tom Abel of Penn State contributed two minutes to the program -- a trek through hundreds of gigabytes of data generated by parallel supercomputers running for several weeks at a stretch.
His work, which goes back to a masters thesis project he began in 1994, considers the life cycle of the first stars in the universe. Inputting initial conditions given by observations of the early universe, Abel considered a primordial cloud of gas a half billion years after the Big Bang.
Because of its own gravity, the cloud began to collapse, eventually giving birth to a star at the center. This proto-galaxy -- with an envelope of gas weighing a million Suns surrounding a single star weighing a hundred -- may well have resembled the Milky Way's first step along the galactic evolutionary ladder.
Abel's work has helped to settle a question of just what the first stars in the universe looked like.
"Some argued that (the gas clouds) would have directly formed a supermassive black hole, while other argued you make low mass stars," he said.
"But what came out was the surprising thing that it's only one star, which has about the mass of a hundred suns," he said.
Abel's computation then followed this one-star galaxy through its sole inhabitant's three-million-year life cycle. Finally, when the star died in a brilliant supernova, he witnessed the shockwaves propagate through the surrounding cloud, potentially seeding the formation of many second-generation stars.
The outcome after the first supernova is still uncertain, though. He hasn't yet carried the simulation through to generation two.
Thanks to Ralf Kaehler of Max Planck and Zuse Institute Berlin, Abel's simulation of the first star from birth to death comprises a luscious two-minute CGI animation in Universe.
The work of Ed Seidel's team at the Max Planck Institute carries the storyline for another couple minutes as they glimpse a system of two black holes spiraling toward one another. Like Abel's work, it represents as much beautiful science as it does pretty pictures.
As black holes orbit one another, they also send out gravitational ripples into space. These signals are now thought to dominate all other sources of gravitational waves in the universe. Naturally, scientists operating gravitational wave detectors -- such as the ones coming online in Germany, Italy and the United States -- want to know what kinds of signals to look for.
Seidel's work -- representing terabytes of data generated over more than a month of supercomputer time -- provides some initial answers.
"This is the kind of problem that really pushes the limits of supercomputing," Seidel said.
One of the most stunning sights in the program comes in the two-and-a-half minute journey from the galactic suburbs where the Solar System sits through the spiral disk and into the Milky Way's bustling central bulge.
The virtual fly-through -- by Donna Cox, Bob Patterson and Stuart Levy of NCSA -- may seem to zip past so many randomly placed globs of stars and clouds. But it actually represents a state of the art map of the galaxy from outer spiral arm to inner black hole.
"Bob Patterson spent many months talking to astronomers about what it looks like and modeling the different features that are in there," Lucas said. "It's just a monumental work."
