How to Use the Free AMNH Digital 3-D Atlas of the Universe
by Brian Abbott & Carter Emmart
Abstract
At the Hayden Planetarium/Rose Center for Earth and Space, a free digital 3-D atlas of the universe has been constructed upon funding from NASA. This model visualizes the 3-D distribution of many astronomical objects as available in academically published data sets. The "Partiview" software used to view the atlas was developed at the National Center for Supercomputing Applications and is open-source free ware. Partiview spans Unix, Linux, and Windows and is scalable from laptop to full dome display. We will demonstrate how to use the interactive viewer and enter one's own data in what we intend to establish as a community building resource.
Preface
While it may be unusual to submit a paper from a workshop session, we would like to take this opportunity to provide a richer explanation and background to our Digital Universe project at the Hayden Planetarium. So, we will mention quicky that you may download Partiview and the Digital Universe from our web site for free. At www.haydenplanetarium.org, you will find instructions on getting the software, the data, as well as a manual describing the software in detail. With this said, we will now discuss the background and history behind the Digital Universe and describe how it will serve the planetarium community.
Introduction
Beginning in 1998, the American Museum of Natural History and Hayden Planetarium created a project to map the three-dimensional structure of the Milky Way Galaxy. This project, called the Digital Galaxy Project (DGP), became a prime objective of what would be the new Hayden Planetarium. Funded by NASA, the DGP created a 3-D Milky Way galaxy that one could explore interactively. Much of these data were used in the inaugural Space Show, Passport to the Universe.
During the production of Passport, we were introduced to a powerful visualization tool called Virtual Director. Developed at the National Center for Supercomputing Applications (NCSA) at the University of Illinois, Virtual Director allowed us to interact with NCSA to craft flight paths for our space show. We used Virtual Director on our production workstation or in the planetarium dome to finalize shots before being rendered.
With the completion of the Rose Center and the Hayden Planetarium in 2000, the DGP was scaled down to accomodate the needs of operation. At about the same time, we were introduced to a desktop version of Virtual Director from NCSA called Partiview. Partiview does not have all the tools that Virtual Director has, but is a slightly stripped down version of the software. We soon began importing our DGP databases into Partiview, exploring whether the software would be suitable for displaying our data.
Soon thereafter, we were awakened to the power of Partiview. Its ease in displaying massive data sets, flexibility in display platforms and operating systems, and its ability to teach even the seasoned scientist the 3-D structure of the galaxy convinced us that this will be an excellent tool for teaching not only astronomy and the night time sky, but also the astrophysics of the galaxy--the science that often remains behind the scenes because adequate visual aids are unavailable.
With this conclusion, we began working with NCSA to foster development of Partiview, enabling a platform for not just the Digital Galaxy, but a Digital Universe. Moving beyond the galaxy, we renamed our venture the Digital Universe. In 2001, AMNH/Hayden was awarded a grant by the NCSA Alliance to distribute and help develop Partiview. We gratefully acknowledge their support.
Rather than outline what we covered in the workshop, we will discuss what the Digital Universe is, how we are distributing the data, and where we see the future development of the Digital Universe, as well as the Partiview software, and how that development will serve the entire planetarium community.
A Digital Universe
The concept of a digital universe is a red-hot topic in astrophysics. The idea of building the computational and data-defined infrastructure to bring a digital universe to your desktop computer is a major priority of the scientific community. This idea of packaging standardized data from many sources and delivering it is called a Virtual Observatory.
We are starting our node of the Virtual Observatory with our release of the Digital Universe (DU). The DU will not simply be data products that are released, but a dynamic database of many types of data, 2-D images, 3-D data distributions, as well as 4-D time-evolving data.
We currently provide our Milky Way Atlas as well as the viewing software, Partiview, free of charge via our web site (www.haydenplanetarium.org). Since its release in March 2002, our Milky Way Atlas has been downloaded from our site over 7000 times. We are creating a large, diverse users group that we hope will continue to expand and flourish.
We expect the DU to be a universally shared atlas for everyone to explore in order to understand our universe. From K-12 teachers to university instructors; from the amatuer astronomer to the planetarian to the astrophysicist. We see the DU as a common meeting place for all who are interested in not only learning about the universe, but contributing to its construction.
To this end, we are committed to providing the DU for free. While its use is not free of restrictions and conditions, it will be free to download.
Creating a Tool for the Planetarium Community
Partiview lends itself perfectly to the planetarium community. While Partiview, itself, does not currently run full-dome, its parent program, Virtual Director does. Currently, Partiview will run on anything from a high-end workstation to an off-the-shelf laptop computer. Hook up a projector to one of these and you have years worth of class content.
One of the main advantages and disadvantages of Partiview is that it is free, open source software. This is a great advantage because the software costs you nothing, and also, because the code will be available to anyone, a more creative development process can take place amongst its users. However, this can be a drawback in that there will be no formal support for the software and open-source software is often not as polished as a commercially-driven product. However, we see the overall advantages far outweighing the disadvantages.
In an effort to make this software more accessible, we are hoping that planetarium display developers will accomodate the use of Partiview and/or Virtual Director in software systems that drive domes. We envision a time when the large and small planetarium can communicate on the same terms by developing content via the same technology. Because Partiview will run on anything from a US$2000 laptop to a high-end workstation, the only thing that could possibly get in the way of this happening is us, the planetarium community.
Planetarium Cross-Talk: Dome-to-Dome Interactivity
In the future, we hope to have the ability to communicate dome to dome. Currently, we are able to do this with NCSA where, using the same software while viewing the same data, NCSA is able to control our dome, and vice-versa. We (NCSA and AMNH) are going to implement this technology into Partiview, allowing remote conferencing abilities. Imagine giving a sky talk to not just your dome, but to classrooms anywhere on the internet.
There are several ways of imagining how cross-communication and remote conferencing might work. One scenario would be a controlled session from the planetarium, broadcasting out to users in something like a on-line class. Another possibility would be full interaction between all users or a subset of users, allowing several planetariums to guide the discussion or a having a discussion with a scientist whose data you are highlighting in a planetarium show. Finally, one could envision a 3-D, on-line chatroom where logging into a Partiview session would place you inside the data, where you could see others who are exploring the universe alongside you. These concepts are not new, however, they lend themselves to getting kids and adults interested in the universe, making the universe more accessible than ever.
Conclusion
The Hayden Planetarium and the American Museum of Natural History have made their database of the Milky Way available and are expanding to include the observable universe. This project, called the Digital Universe, is available from our web site (www.haydenplanetarium.org). Along with these data sets is the software, Partiview, used to interactively view the data. The results of both of these publicly-funded projects are available for free. We intend to build a diverse group of users and developers who will contribute to the software as well as the construction of a Digital Universe. In addition to the planetarium community, we are serving K-12 and university educators, scientists, as well as the lay-person with varying levels of interest in astronomy. The Digital Universe, along with Partiview, has the ability to engage on a level that does not compare to other methods of teaching. We hope that you will discover and explore the universe with us and help to build a tool for all of us to share.