3D Astrophysics Newsletter

2016_6_12_garate6.12 Today´s new entry:

Voxel datacubes for 3D visualization in Blender

Matías Gárate

Abstract: The growth of computational astrophysics and complexity of multidimensional datasets evidences the need for new versatile visualization tools for both analysis and presentation of the data. In this work we show how to use the open source software Blender as a 3D visualization tool to study and visualize numerical simulation results, focusing on astrophysical hydrodynamic experiments. With a datacube as input, the software can generate a volume rendering of the 3D data, show the evolution of a simulation in time, and do a fly-around camera animation to highlight the points of interest. We explain the process to import simulation outputs into Blender using the Voxel Data format, and how to set up a visualization scene in the software interface. This method allows scientists to perform a complementary visual analysis of their data, and display their results in an appealing way, both for outreach and science presentations.

Comments: Accepted on November 17, 2016, 14 pages, 5 figures
PASP Focus Issue: Techniques and Methods for Astrophysical Data Visualization
URL of preprint: https://arxiv.org/abs/1611.06965
Submitted by: Matías Gárate


3D Astrophysics Newsletter

2016_6_11_hanus6.11 Today´s new entry:

Shape model of asteroid (130) Elektra from optical photometry and disk-resolved images from VLT/SPHERE and Nirc2/Keck

Josef Hanus, Franck Marchis, Matti Viikinkoski, Bin Yang, Mikko Kaasalainen

Abstract: Asteroid (130) Elektra belongs to one of the six known triple asteroids in the main belt, so its mass has been reliably determined. We aim to use all available disk-resolved images of (130) Elektra obtained by the SPHERE instrument at VLT and by the Nirc2 of the Keck telescope together with the disk-integrated photometry to determine its shape model and its size. The volume can be then used in combination with the known mass to derive the bulk density of the primary. We apply the All-Data Asteroid Modeling (ADAM) algorithm to the optical disk-integrated data, 2 disk-resolved images obtained by the SPHERE instrument and 13 disk-resolved images from the Nirc2 of the Keck telescope, and derive the shape model and size of Elektra. We present the shape model, volume-equivalent diameter (199±7 km) and bulk density (1.60±0.13 g cm−3) of the C-type asteroid Elektra.

Journal: Astronomy & Astrophysics, accepted November 9
URL of preprint: https://arxiv.org/abs/1611.03632
Submitted by: Josef Hanus

3D Astrophysics Newsletter

2016_6_11_vogt6.11 Today´s new entry:

Linking the X3D pathway to integral field spectrographs: YSNR 1E0102.2-7219 in the SMC as a case study

F.P.A. Vogt, I.R. Seitenzahl, M.A. Dopita, A.J. Ruiter

Abstract: The concept of the X3D pathway was introduced by Vogt et al. (2016) as a new approach to sharing and publishing 3-D structures interactively in online scientific journals. The core characteristics of the X3D pathway are that: 1) it does not rely on specific software, but rather a file format (X3D), 2) it can be implemented using fully open-source tools, and 3) article readers can access the interactive models using most main stream web browsers without the need for any additional plugins. In this article, we further demonstrate the potential of the X3D pathway to visualize datasets from optical integral field spectrographs. We use recent observations of the oxygen-rich young supernova remnant 1E0102.2-7219 in the Small Magellanic Cloud to implement additional X3DOM tools & techniques and expand the range of interactions that can be offered to article readers. In particular, we present a set of javascript functions allowing the creation and interactive handling of clip planes, effectively allowing users to take measurements of distances and angles directly from the interactive model itself.

Comments: 8 pages, 6 figures, online interactive model: http://fpavogt.github.io/x3d-pathway/YSNR.html Github repo: https://github.com/fpavogt/x3d-pathway/tree/master/x3d_to_html/1E0102

Journal or Name of Publication: accepted for publication in PASP’s special edition “Techniques and Methods for Astrophysical Data Visualization”
URL of preprint: https://arxiv.org/abs/1611.03862
Submitted by: Frédéric Vogt

3D Astrophysics Newsletter

2016_6_10_taylor6.10 Today´s new entry:

Visualising three-dimensional volumetric data with an arbitrary coordinate system

Rhys Taylor

Abstract: Astronomical data does not always use Cartesian coordinates. Both all-sky observational data and simulations of rotationally symmetric systems, such as accretion and protoplanetary discs, may use spherical polar or other coordinate systems. Standard displays rely on Cartesian coordinates, but converting non-Cartesian data into Cartesian format causes distortion of the data and loss of detail. I here demonstrate a method using standard techniques from computer graphics that avoids these problems with 3D data in arbitrary coordinate systems. The method adds minimum computational cost to the display process and is suitable for both realtime, interactive content and producing fixed rendered images and videos. Proof-of-concept code is provided which works for data in spherical polar coordinates.

Journal: PASP Special Focus Issue: Techniques and Methods for Astrophysical Data Visualization
URL of preprint: https://arxiv.org/abs/1611.02517
Comments: Accepted November 7, 2016, 6 pages, 5 figures
Submitted by: Rhys Taylor

A ginormous stereoscopic viewer


Cassini space probe view of clouds on Saturn´s north pole region (NASA).

It seems popular among children, the word “ginormous” and it feels like the best fitting description for the biggest pair of binoculars on Earth…around Earth, I should say. Green et al. (2016) recently described the potential of having two big optical/infrared space telescopes operating at the same time: Hubble and Webb working as a team to see space in 3D! Sounds like a pretty amazing idea. I know, you are already sitting at the edge of your seat and can´t wait for Webb to be launched next year. Continue reading