OpenCosmos

OpenCosmos

Main Goal of Open Cosmos Project is to offer an opportunity to easily visualise public datasets.

Open Cosmos Project was originaly designed for visualisation of astronomical datasets, connected with our knowledge of our Univers, such as planets, asteroids, stars, galaxies, pulsars...

A growing number of datasets are now available over Internet. Those catalogs, made by university, laboratories, observatories, are focused on sharing maximum data collected for every objects. But those datasets are not designed for visualisation. Every dataset is specialised on a type of object, or on a type of parameters. Every dataset as its own format.

In the same time, a growing number of astronomical visualisation software are also accessible over internet, such as stellarium, celestia, Microsoft WorldWide Telescope, NASA WorldWind, google earth, google sky, google mars, google moon... Also a number of professional softwares are working on the same goal, visualising our Univers.

All those softwares try to integrate those datasets, as a result, software's developpers that wants to add the visualisation of those data must work on their own functions to load and modify a particular dataset.

Open Cosmos Project was created to offer a unified tool to load public datasets, modify those datasets, and save those datasets in a particular 3D visualisation format.

Open Cosmos Project main goal is to share all necessary tools to allow a maximum of application to acces and visualise public datasets.

• a catalog of datasets can already be load by Open Cosmos Input Plug-ins
• to load a specific dataset, anyone can write an Input plug-in and share this with community (by joining the community, you must accept to share this work)
• to make some traitment on the dataset, you can use or write a process plug-in (and decide to share it or not)
• to allow your application to visualise any dataset loaded by Open Cosmos, you can use Open Cosmos Output plug-ins, or write your own (and decide to share it or not)

Open Cosmos Project was originaly developped, and is currently managed by RSA Cosmos.

Open Cosmos Builder Features

Input plugins

To allow a dataset to be visualised by any application, an Input plug-ins is necessary. This input plug-in reads a dataset file and store the dataset in a OpenCosmos database. Input plug-ins reads field of the dataset, and may also calculate new field. (For example: In Hipparcos catalog, you can find parallaxe information as well as alpha, delta of a star, with those information you can compute X,Y,Z position of a star with error associated)

Process plugins

Once dataset is loaded (original fields as well as computed fields), process plugins allow to manipulate a OpenCosmos database : save current OpenCosmos Database, modify OpenCosmos Database(sort, remove, ...), load in the current OpenCosmos Database a previous OpenCosmos Database.

Output plugins

Once datas are ready, you've to use Output plugins to save them in the format you want. The most common is raw file but you're able to ouput an osg file (see OpenSceneGraph) then visualise with OpenCosmos Viewer..

Viewer

OpenCosmos provides a basic viewer based on OpenSceneGraph viewer. It reads .osg files (or .ive files which are osg converted in binary code). OpenCosmosViewer is available on free download and contains a file including datas from catalogs presented in the section Catalogs. Moreover, you can also visualized planet's orbital trajectory.

If you use our original osg file, each catalog possesses its own color (easily modifiable in osg files), except Hipparcos :

• V8k is green
• Sdss is magenta
• Astrob is Cyan
• Comet is yellow
• 2qzqso is red
• 2dfgrs is white
• Hipparcos stars's color and size depends on the colorBV, related to the magnitude of the star (using simple Vertex Shader)