  We present the first 3D prints of output from a supercomputer simulation of a
complex astrophysical system, the colliding stellar winds in the massive (>120
M_Sun), highly eccentric (e ~ 0.9) binary star system Eta Carinae. We
demonstrate the methodology used to incorporate 3D interactive figures into a
PDF journal publication and the benefits of using 3D visualization and 3D
printing as tools to analyze data from multidimensional numerical simulations.
Using a consumer-grade 3D printer (MakerBot Replicator 2X), we successfully
printed 3D smoothed particle hydrodynamics (SPH) simulations of Eta Carinae's
inner (r ~ 110 au) wind-wind collision interface at multiple orbital phases.
The 3D prints and visualizations reveal important, previously unknown
'finger-like' structures at orbital phases shortly after periastron (phi ~
1.045) that protrude radially outward from the spiral wind-wind collision
region. We speculate that these fingers are related to instabilities (e.g.
thin-shell, Rayleigh-Taylor) that arise at the interface between the
radiatively-cooled layer of dense post-shock primary-star wind and the fast
(3000 km/s), adiabatic post-shock companion-star wind. The success of our work
and easy identification of previously unrecognized physical features highlight
the important role 3D printing and interactive graphics can play in the
visualization and understanding of complex 3D time-dependent numerical
simulations of astrophysical phenomena.
