The small crammed room was packed with students eager to learn something about 3-D animation for astronomy. It was during the summer of 2001 at the University of Guadalajara, Mexico. As an introduction to the course, I showed a few demo animations and stopped at one particular image. I asked them one by one what they saw. The coincidence in the order they were seated made possible what was a revelation to me . It set me up for a mission.
5.10 Today´s new entry:
Three-Dimensional Orientation of Compact High Velocity Clouds
F. Heitsch, B. Bartell, S.E. Clark, J.E.G. Peek, D. Cheng, M. Putman
Abstract: We present a proof-of-concept study of a method to estimate the inclination angle of compact high velocity clouds (CHVCs), i.e. the angle between a CHVC’s trajectory and the line-of-sight. The inclination angle is derived from the CHVC’s morphology and kinematics. We calibrate the method with numerical simulations, and we apply it to a sample of CHVCs drawn from HIPASS. Implications for CHVC distances are discussed.
Journal or Name of Publication: MNRAS Letters
URL of preprint: https://arxiv.org/abs/1606.06689
Comments: 5 pages, 4 figures, accepted June 21 2016
Submitted by: Fabian Heitsch
5.9 Today´s new entry
NGC 2440 : A morpho-kinematical model
Paulo J.A. Lago, Roberto D.D. Costa
Abstract: This work describes the modelling of the 3D structure and position-velocity (P-V) diagrams of NGC 2440, a well known planetary nebula, aiming to describe the morphology of this object, specially its core. We have used high resolution spectra and P-V diagrams to reproduce the 3D structure of the nebula using SHAPE, a software that allows 3D modelling. HST high angular resolution images were used as reference to the model.
The observational data point to a segmented core, and the simulations confirm this assumption; the best model for the nebula is a torus segmented in three pieces. The simulated P-V diagrams agree with the observations. We suggest that the torus was torn apart by interaction with the surrounding medium, either as winds or the radiation field.
For the two bipolar lobes, orientation angles to the plane of the sky of 27±5 and −5±3 degrees, respectively for the bipolar components with PA of 85 and 35 degrees, were derived. No additional bipolar lobes were required to model the observed features of NGC 2440. A distance of 1.8±0.5 kpc was derived for the nebula using our velocity field for the toroidal structure. These results are the first derived for NGC 2440 from modelling in a 3D environment.
Journal or Name of Publication: Rev. Mex. de Astronomía y Astrofísica (RMAA), in press
URL of preprint: http://arxiv.org/abs/1606.01234
Submitted by: Paulo J.A. Lago