CS 526 Project 2

The purpose of this project is to give you experience using high-resolution large format display to view small multiples. In this case we will be looking at the ever-increasing number of exoplanets that have been discovered. You will also be learning something about astronomy.

For this project you will use OmegaLib and the CAVE2 to show data on the current set of planets outside our solar system that have been discovered. We will show information about various systems on the walls as a form of small multiples and show one or more systems in the center of the cave in detail.

Scale is always a huge issue when dealing with astronomical bodies since its usually impossible to show everything in scale - typically you can either show distances between objects in scale, or the size of various objects in scale, but not both at the same time. The different types of stars also have very different habitable zones, and we have discovered an extremely wide range of planetary distances from their star. We also have binary, trinary, etc star systems.

Some good sources of information:

Exoplanet Data Explorer - http://exoplanets.org/table?datasets=explorer
NASA Exoplanet Archive - http://exoplanetarchive.ipac.caltech.edu
Open Exoplanet Catalogue - http://www.openexoplanetcatalogue.com
Extrasolar Planets Encyclopedia - http://exoplanet.eu
Wikipedia Stellar Classification - http://en.wikipedia.org/wiki/Stellar_classification
Wikipedia - Our Solar System - http://en.wikipedia.org/wiki/Solar_System
Wikipedia - Habitable Zones - http://en.wikipedia.org/wiki/Habitable_zone
Wikipedia - List of exoplanet Host Stars - http://en.wikipedia.org/wiki/List_of_exoplanetary_host_stars
Wikipeia - List of Multiplanetary Systems - http://en.wikipedia.org/wiki/List_of_multiplanetary_systems
NY Times graphic on habitable zones - http://www.nytimes.com/interactive/2011/12/03/science/space/1202-planet.html?_r=0

You should start with our solar system with its single star and 8 major planets. One of the small multiples on the sides of the CAVE should always show our solar system for comparison with the others, and our solar system should always be available to view in the center of the CAVE for comparison. The sun and the various planets should be modeled as spheres with appropriate textures. For the small multiple version you should be able to see the name of the system, the type of star, how far this system is away from us, how the planets were discovered, the distance from the star to each of the planets, the identifying name of the planet, the relative sizes of the planets, and the location of the habitable zone for that star. Within the CAVE you should have the planets with their identifying name orbiting the named star at an appropriate distance, with an appropriate relative size and texture, and orbiting at an appropriate rate, and show the habitable zone for the star. You should allow the user to change the scale of the orbits, the scale of the planets, and the speed that time passes as the planets orbit.

The system should be head and hand tracked. As the user walks around the CAVE, the solar system in the CAVE should update appropriately while the small multiples on the walls of the CAVE stay where they are. Users should be able to point at one of the solar systems shown on the walls using the wand and bring it into the CAVE.

You should not be building the various solar systems one by one by hand. Given the data on the various planets of each solar system you should be able to automatically generate a visualization for each one. However, as you add more and more systems to your visualization you will see more and more oddities where you will need to tweak your visualization so it is useful. For the other planets you will need to find some appropriate textures - a good place to start is http://www.celestiamotherlode.net. You need to show the different kinds of stars in some appropriate way.

You will also find that the different detection methods give different information about these planets, so some assumptions need to be made to combine the datasets. Sometimes we know the radius and sometimes we know the mass. Unfortunately without knowing the composition of the planet we can not directly correlate these, but we can do some general correlations. One such way is given below. There are others. Pick and defend an appropriate method.

earth-sized ( < 1.25 X radius of earth) < 2 times mass of the earth
super earth (1.25 - 2 X radius of earth) 2 - 5 times mass of earth
mini-neptune ( 2- 3 x radius of earth) 5 - 10 times mass of earth
neptune sized ( 3 - 6 X radius of earth) 10 - 30 times mass of earth
jupiter sized ( 6 - 15 X radius of earth) 30 - 300 times mass of earth
super-jupiter ( > 15 X radius of earth) > 300 times mass of earth

Another issue is how to compute the habitable zone. There are multiple theories on this as well, e.g. http://www.planetarybiology.com and http://www.astronomy.ohio-state.edu/~pogge/Ast141/Unit5/Lect34_StarHZ.pdf. It would be best to base this off the luminosity of the star, but we can get some general information from the type of the star:

A - inner = 8.5 AU, outer = 12.5 AU
F - inner = 1.5 AU, outer = 2.2 AU
G - inner = 0.95 AU, outer = 1.4 AU
K - inner = 0.38 AU, outer = 0.56 AU
M - inner = 0.08 AU, outer = 0.12 AU

Note that you are expected to learn some astronomy as part of this assignment. You will need to do research to complete this project.

Here is a snapshot of the proof of concept app that I wrote in omegalib for this assignment showing 64 small multiples on the walls of the CAVE and one exo-planetary system in the center of the CAVE. This should give you an idea of the way the app could be realized, but there are things that I would do better if I was writing it again.

The code for this example is given here

To get a C on the project ...

Create a usable, visually appealing small multiples visualization of at least 48 planetary systems (including our own) as described above
Any change in any of the scale factors should be reflected in all of the views simultaneously so they are easy to compare
If one or more of the planets is not visible in the current small multiples view (i.e. its outside the current scaled view) show an appropriate indication of that.
Show our solar system animated in the center of the CAVE in 3D
Start time progressing, so the planets will begin to orbit their parent star in the CAVE, and be able to change the rate of time passing
Either be able to fly around the solar system in the CAVE or move the solar system in the CAVE, leaving the small multiples on the walls where they are
Be able to reset the views back to a default view
Make appropriate use of audio in your application
Have menu and controller options to change scale of the planet size, orbit size
Each of the small multiples should show the name of the planetary system, distance from our solar system in light years, and the type of star, how the planets were discovered, current identifying name for each planet
Have a predefined set of 4 different interesting sets of planetary systems (e.g. nearest to the Earth, most likely to be habitable, etc) to view on the walls based on different parameters in a menu and be able to switch between them

To get a B you need to add ...

Use the wand to choose one of the currently visible planetary systems on the wall to bring into the center of the CAVE to view in 3D. Be able to show our solar system for comparison.
Move beyond the 4 sets of planetary systems to dynamically filter which systems are currently shown on the screens
Highlight the earth sized planets in the habitable zones and larger planets that may have habitable moons orbiting in the habitable zones
Create another 3d view in the CAVE showing where all the various small multiple stars are relative to our sun and the other nearby stars (e.g. a bunch of coloured balls in 3-space), and highlight the system(s) that is/are currently shown larger in the CAVE.
Allow the user to dynamically move individual small multiple systems around to reorder them manually, and remove systems from the wall
Show the error margins in the estimates. Much of the data is +/- some amount.
Allow the user to save off configurations of the small multiples systems

To get an A you need to add ...

Find a good way to deal with binary and trinary systems
Look up some current research discoveries and highlight these things in your interface / visualization
Impress me with additional features

Also note that there is a big difference between getting something working and getting it working well. The first is not that hard. The second takes much more time. You are expected to have things working well.

I highly recommend visualizing a variety of data into your application quickly, beyond our solar system, to start seeing the real issues you will be encountering in creating a good interactive visualization environment.

To turn in your project you should set up a web page with several pages describing your work, including the well-commented source code and required files to be able run your program in the cave, and some photographs showing what your application looks like when its running. You should then email andy with the location of this website before the deadline. It would probably be a good idea to put a backup copy of the web page at a second website just in case I can't get to the first one.

all of which should have plenty of screenshots with meaningful captions.

Be sure to document any external libraries or tools that you make use of - give credit where credit is due.

You should also create a 2-3 minute YouTube video in the CAVE showing your application running and feature the video prominently on your project webpage. The video should be narrated and rehearsed to show off the important features of your project.

Remember that this site may be useful to you later on when you are looking for a job and want to show off the projects you have done.

Project 2 - Straight Away to Orion