1. Shape: A 3D Modeling Tool for Astrophysics. Wolfgang Steffen, Nicholas Koning, Stephan Wenger, Christophe Morisset, Marcus Magnor. IEEE Transactions on Visualization and Computer Graphics, Vol. 6, No. 1. January 2007. ​arXiv Link. Submitted to arXiv 10-03-2010.

Outline:

Under Construction

1. Introduction

• Claims that the development of "effective methods for the reconstruction of the 3D structure of astrophysical objects is […] an issue of growing importance in astronomy."
  • Astrophysical photographs only provide a 2D integration (some sort of column density map, if you will) of the emission and absorption along the line of sight.
    • No information with regard to the depth of the object photographed.
  • Some objects have symmetry properties that allow for a more "automatic reconstruction," i.e. Planetary nebulae (PPN, PN).
  • No symmetries? Can determine the depth from information contained in the velocity field.
    • Some astrophysical objects cannot allow for such a mapping, i.e. Interstellar clouds.
• What about the current methods used in computational astrophysics? Astrophysical modeling utilizes parallelized codes on supercomputers (like AstoBEAR).
  • Authors claim: "While such simulations produce insight into generic astrophysical processes, they are rarely suitable for elucidating the properties and structure of particular objects." What properties and what objects?
    • Planetary nebulae in particular. (Why? Symmetry reasons? Hard to apply dynamically?)
    • "For the correct physical interpretation of observational data, information about the object's 3D shape has to be available. Obtaining new structural information and insight on particular objects is the main purpose of the application of [Shape]."
• Morpho-kinematical: As applied to modeling involves only structural (morphological) and velocity (kinematic) information.
  • In contrast to dynamical simulations: Include effects of forces and temporal evolution from a set of simpler initial and boundary conditions.
    • "…, the outcome of dynamical simulations is not predictable in detail and very hard to tune to a specific object."

Ultimately authors claim Shape will remedy the shortcomings of the current state of astrophysical reconstructions by applying structure modeling techniques of commercial animation softwares, while adding systems that are necessary for astrophysical research. They implement more physically accurate modeling of radiation transfer from the sources to the observer.

2. Related Work

2.1 Automatic-Reconstruction Methods

2.2 User-Driven Systems

3. Observational Data in Astronomy

4. The Shape System

4.1 Java Implementation

4.2 Interactive Modeling

4.3 Image Rendering

4.4 Synthetic Observation

4.5 Automatic Optimization

4.6 Automatic Reconstruction

4.7 Plot, Animation, and Movie Modules

5. Results and Example Applications

5.1 Validation of Shape with Hydrodynamical Simulations

5.2 Reconstruction f the Saturn Nebula

5.3 Nova RS Ophiuchi

5.4 Content production for digital media

6. Future Developments

7. Conclusions