Hanson, Andrew


Read here about a researcher who has contributed to the comprehension of scales.

Power-scaled Coordinates

A graphics software system that provides a continuously scalable visualization in three dimensions.
Graphics displays have faced a limitation due to their digital nature, for example, handling large ranges in detail is out of the range of standard hardware, such as accelerated graphics cards. With this new system, we can create an accurate, interactive experience, with continuous scaling over different scale ranges. You can wander continuously throughout the universe without any anomalies.
Fu and Hanson’s power-scaled coordinates (PSC) system works by representing coordinates and vectors using logarithmic scaling methods, enabling the system to handle all scales in a single context for interactive control by the user. One of the novel PSC-based ideas in the architecture is a “depth rescaling method,” which can project objects across extreme scales with the needed precision by distorting the vertices of distant background objects.
Employing this architecture, we have developed an assortment of scale-independent modeling and rendering methods for a large variety of astronomical models, and have demonstrated scale-insensitive interactive visualizations of the physical Universe covering scales ranging from human scale to the Earth, to the solar system, to the Milky Way Galaxy, and to the entire observable Universe.

From January/February 2007 (Vol. 13, No. 1) pp. 108-121, A Transparently Scalable Visualization Architecture for Exploring the Universe, by Chi-Wing Fu and Andrew J. Hanson.

Cosmic Clock

Cosmic Clock is a 3:35 minute photo-realistic animation that makes overt the time dilation involved in macro-scale visualizations. See Cosmic Clock Video by Hanson.

Satellites that surround the Earth By Hanson

An animated GIF by Hanson.

Heliopause

Hanson's Heliopause animation takes place at a 10^15 meter scale.

Text from the website:

This animation of the heliosphere in our galactic neighborhood illustrates the true geometry of the heliosphere and planetary system with respect to the plane of the Galaxy and nearby stars. In this animation, the viewpoint changes as we navigate around the solar location in space. The background image of theMilkyWay Galaxy is from AxelMellinger, and the displayed stars are from the Hipparcos catalog . The heliosphere model is based on an MHD model, which includes an interstellar magnetic field. This MHD model is based on heliosphere properties during the 1996 solar minimum.


Scalable World-in-miniature Map


Scalable WIM: Effective Exploration in Large-scale Astrophysical Environments, by Yinggang Li, Chi-Wing Fu, Andrew J. Hanson.

Astronomers mapping the Universe are challenged by a wide variety of scales. The figure presents a comprehensive map of typical objects at different spatial scales in our physical Universe. The x axis is the base 10 logarithm of distance relative to the Sun in meters. We can see from the map that there are 27 orders of magnitude in distance to the boundary of observable Universe: the Earth (distance scale: ~10^11m), the solar system scale (~10^13m), the nearest star to our Sun (interstellar scale: ~10^17m), the center of the Milky Way Galaxy (galactic scale: ~10^21m), and galaxy clusters (intergalactic scale: ~10^24m). Throughout these scales, space is mostly empty. In an exploration tool, we want to support a wide range of exploration capabilities, from our own solar system out to the large scale structure of galaxy groups. The challenge is thus to design mechanisms that can represent the entire observable Universe through a unified interface with proper emphasis on non-empty space.

From the WIM abstract

We introduce a new technique called the scalable worldin- miniature (WIM) map as a unifying interface to facilitate travel and wayfinding in a virtual environment spanning gigantic spatial scales: Power-law spatial scaling enables rapid and accurate transitions among widely separated regions; logarithmically mapped miniature spaces offer a global overview mode when the full context is too large; 3D landmarks represented in the WIM are enhanced by scale, positional, and directional cues to augment spatial context awareness; a series of navigation models are incorporated into the scalable WIM to improve the performance of travel tasks posed by the unique characteristics of virtual cosmic exploration. The scalable WIM user interface supports an improved physical navigation experience and assists pragmatic cognitive understanding of a visualization context that incorporates the features of largescale astronomy.

Below, 1st person view of the solar system in a virtual Universe exploration, a context-cue-rich WIM offering new perspective into the local environment (middle), including a camera manipulator for view specification, and a logarithmic eye space remapping of the same scene exposing the scales in a global context (right).

Image Gallery Of Wim


Hanson_1st_person_view_of_solar_system.png
First person view of solar system by Hanson.

Hanson_logarithmic_eye_space_remapping_of_the_same_scene_exposing_the_scales_in_a_global_context.png
The logarithmic Sun-centered distance map of sky landmarks (in meters) illustrating the enormous scale range of the observable Universe: nearest star Proxima Centauri (∼10^17m); Hipparcos Star Catalogue (∼1019m); Boundary of Observable Universe (Quasars, etc.) (∼10^27m).

Hanson_WIM_Context_Cue_Rich_Sample_at_10^12.png
Hanson WIM Context Cue Rich Sample at 10^12

Hanson_WIM_logarithmic_Sun-centered_distance_map_of_sky_landmarks_(in_meters).png
Hanson logarithmic eye space remapping of the same scene exposing the scales in a global context