Synthetic Nebulae

 

Orion 00000
Orion 00001
Orion 00006
Orion nebula

The Orion Nebula is visible to the naked eye as a blurry patch near Orion's belt. 1500 light years from earth, the nebula is the birthplace of stars. Four central stars, called the "Trapezium", make the surrounding hydrogen, oxygen, and nitrogen gasses glow in reds and yellows. Their light reflects off of dust in the nebula, adding light blues to the nebula's colors. The colors mix to give the nebula a greenish cast. Nestled within the nebula are hundreds of tear-dropped shaped clouds that surround new-born stars and their proto-solar systems. All of this is visible within high resolution Hubble Space Telescope images. Infrared images and astrophysics simulations infer a 3D structure to the nebula, revealing a bowl-shaped cavity in the center and ripples along its sides and bottom.

In 1999, the American Museum of Natural History in New York City contacted us to create a volumetric visualization of the Orion Nebula using the latest 3D structure and Hubble images. These images are portions of a full-dome planetarium show created for the museum and now showing world-wide. The model began as a polygonal surface for the nebula's inner cavity. The model was digitized into a volume and its surface purturbed with controlled turbulence. A color-corrected Hubble image of the nebula was projected through the volume. An additional 100 smaller volumes were created in the same way to model the proto-solar systems and shock fronts within the scene. The collection of volumes were managed within a "volume scene graph" and rendered using a custom volume renderer that implemented optical edge brightening effects. The animation was rendered using the San Diego Supercomputer Center's 1000+ processor supercomputer.

This project was funded by the American Museum of Natural History in New York City. Development was in C++.

Emission 2200
Emission 3400
Emission 4000
Simulated emission nebula

The dust and gas of a nebula is not evenly distributed. Clumps form and grow. As they grow, their gravity increases and they pull in more neighboring dust and gas. Gradually, over millennia, the clumps grow larger, denser, and hotter. Soon they ignite into a star. Their energy makes the surrounding gas glow like a neon light. That energy also begins to push away neighboring gas as if by a wind. This clears the area and creates a cavity within the nebula. Other newborn stars in the same nebula contribute their energy to make the cloud glow and enlarge the cavity. From Earth we see a snapshot in time of this on-going process. But with astrophysics simulations we can speed up time and watch stars form within the nebula.

In 2001, the American Museum of Natural History in New York City again contacted us to help visualize the formation of a nebula. Using several back-to-back astrophysics simulations and multiple terabytes of data, we modeled a nebula that gradually condensed into stars. A central star ignited and the nebula burst into color. Volumetric image processing filtered the data and transfer functions set opacity. Colors were set based upon star proximity and the simulated gas content. The collection of animated volumes were rendered using a custom volume renderer that implemented optical edge brightening effects and took advantage of high-parallelism available on our supercomputer. The resulting animation is part of the planetarium's full-dome show and is no showing world-wide.

This project was funded by the American Museum of Natural History in New York City. Development was in C++.

Nadeau software consulting
Nadeau software consulting