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“In order to make an apple pie from scratch, you must first create the universe.” - Carl Sagan1 Introduction The use of visual effects in scientific visualization is essential to understanding the events of the universe that cannot be seen through natural human perception. Throughout the cosmos, phenomena occur every day that cannot be seen by the human eye because the vast majority of all light and energy in the universe lies outside the visible spectrum. Compared to the timescales of most celestial events, human lifetimes are relatively insignificant. Space travel is still extremely limited, so all astronomical events are studied from a great distance through automated probes or by peering through telescopes. Because of this, the science of astronomy is studied, tested and hypothesized entirely through observation alone. The continual advancement of visual effects technology has made a significant impact on the ability to visualize cosmic phenomena. In a science, such as Astronomy, that relies entirely on visual observation, it is only logical that the use of visual effects holds a much more significant role than in other scientific disciplines. Short History of Astronomical Visualizations The first attempts to visualize the heavens can be seen in early celestial 1 COSMOS Episode 1 2 maps.A Most of these were centered on defining the different constellations and attributing mythical or religious significance to their existence. Islamicate celestial globes, created as early as the sixth century B.C., are perhaps the oldest detailed representations of the heavens visualized in three dimensions (figure 2).B They are of significance because they demonstrate an early understanding that the earth is indeed not flat. Like all celestial maps from the ancient world, they were based upon observations of the positions of stars visible with the naked eye and represented with constellations inferred from the patterns seen in the stars. An interesting feature of these globes is that the stars were always shown in reverse from how they would be seen on earth, as if the observer were floating outside the sphere of the stars and looking in on them. As the science advanced, the motion of the stars and planets became better understood and the mythology around the heavens began to lose some of its significance. By far, the most important use of celestial mapping was for navigational purposes, so accuracy became of vital importance (figure 3).C The planets of our solar system posed a problem for still map makers because of their seemingly erratic paths in the sky. To the naked eye, the planets appear as points of light just like the stars, but while the stars all move along the same path, the planets seemed to follow an entirely different pattern. The invention of the telescope revealed the planets as different bodies from the stars. Kepler’s laws of planetary motion and the realization that the Earth and other planets orbit the sun helped unravel the mystery of their movement. Based upon these new discoveries, moving maps of the solar system, also known as orreries 3 were developed. An orrery (figure 4) D is a mechanical model of the solar system, named for the Fourth Earl of Orrery, who is credited with their invention. 2 The size and distance of the planets is altered, but otherwise, they are remarkable in their accurate representation of planetary motion. These were all simply different forms of visual media utilized to enhance our understanding of the world in which we live. Whether based on mythology or solid observational science, the common theme was to better see what was happening or to translate the slow moving, mysterious heavens into a concise and easy to understand image. As observations yielded more accurate data, the visualizations improved. Better visualizations helped to foster more informed theories, which in turn led to better observations. This symbiotic relationship between the science and the visualization has helped to advance concepts, practices and technology related to both. How Scientific Visualization is Useful Humans need to visualize problems to fully understand them, but the natural human experience is limited. For the purposes of this exploration, four main areas of human limitations will be discussed: 1. The human eye can only see a tiny fraction of the total spectrum of light and energy. 2. Some celestial events emit no known electro-magnetic energy and are therefore truly invisible. 3. Compared to celestial time-scales, human lifetimes are extremely short. 2 Mapping of the Heavens, p. 101 4 4. Space travel is limited and the physical scale of the universe makes direct observation of any celestial event or phenomena is virtually impossible. Different technologies and techniques are developed to record the information from various celestial phenomena that cannot be naturally observed. The data collected must then be translated into a visual form in order to be studied and understood. Exploring the Visual Spectrum The human eye can only perceive a tiny fraction of the light and energy present in the universe (figure 5).E Using visual effects techniques, these events can more fully be understood. Most cosmic events occur in the ‘invisible’ wavelengths outside the visible spectrum. The human eye cannot see this light, but specialized equipment can. These images are recorded in grayscale as a single channel image from one isolated band of light. Multiple exposures to different wavelengths are captured and recorded. To fully understand what’s being seen, the different grayscale images are combined in the same way a photograph would be exposed; one image for the each of the red, green and blue channels. As an example, the Egg Nebula (CRL 2688)3 shows the remnants of a dying star. Though it is visible to the naked eye, much more energy is being emitted from the ‘invisible’ wavelengths of light and energy, as seen in figure 6.F Truly Invisible Phenomena 3 NASA source 5 Phenomena such as black holes and dark matter emit no light at all, therefore it is impossible to see them without the aid of visual effects techniques. Extrasolar planets are discovered by astrometrics, or observing the wobble of a star’s motion. The planets are not seen, but their presence is made apparent by their effect on the motion of the stars they orbit. The visualization of black holes is done by observing the effects of a black hole on the objects around it and how the light is altered by its presence. Various methods can adequately represent these phenomena, but through the visual effects techniques of advanced 3D animation, a more complete picture can be presented. <video of black hole visualized <figure 8 – DVD 1>> G Dark matter, or the “scaffolding of the universe,”4 is visualized in a similar manner. Because dark matter does not emit or absorb light like regular, visible matter, it cannot be observed directly. Instead, its presence is extrapolated by noting the distortions of the light that passes through it. To visualize this, the COSMOS survey uses five different telescopes; three in space, and two on earth. Each of the five telescopes surveys the same section of sky at slightly different angles. The five images are combined into the composite image shown in red in figure 9.2. The blue image on the right shows the extracted distortions from the composite image. This process is repeated at three different distances; 3.5 billion, 5 billion and 6.5 billion light years away. These three images are then lined up in virtual 3D space based upon their actual distances from each other. A complete 3D model can then be extrapolated from these three images representing the approximate location of dark-matter in the universe.H <image of 4 Dark Matter 6 dark matter <figure 9>> Compressing Time, Size and Distance to Human Scales Our solar system is quite small in comparison with the size of our own galaxy. Our galaxy is merely an average sized galaxy in a universe with billions of other galaxies, each of which is incredibly far apart. It would take several lifetimes for a space ship to travel to the nearest star. To help understand the size of the solar system, a scale model was built in Maine. At 1:93,000,000 scale, the planets were built at correct sizes and distances from each other. From the Sun to Pluto, the model spans 40 miles5 While this is a unique and innovative representation of the scale of the solar system, its size makes it impossible to view the entire model. Cheating the sizes or animating a virtual camera through the solar system would be the only way to experience the 3 billion, 720 million miles distance from the sun to Pluto all at once. Analogy is an effective method to demonstrate many cosmic events, as seen with Carl Sagan’s ‘Cosmic Calendar,’6 but the use of visual effects can provide a more direct alternative to the abstraction of these analogies. Digital visual effects animations are particularly well suited to representing scale and time. Through animations and digital models, events, such as the beginning of the universe, the birth of the moon or the eventual demise of our own Sun can be shown in a direct and realistic way. 5 6 http://www.umpi.maine.edu/info/nmms/solar/ COSMOS Disk 1? 7 Accuracy in Scientific Visualization Artists developing scientific visualizations have a great responsibility to remain mindful of the power of the image to create the illusion of truth. The image often holds its own authority over the facts, regardless of its accuracy.7 One of the greatest challenges in scientific visualization, and indeed, all visual effects relating to natural phenomenon, is the balance of accuracy and aesthetics. This balance is dependent entirely on the intended audience and the purpose of the visualization. As the audience shifts towards the technical realm, the accuracy becomes more important and as the audience shifts towards the entertainment realm, the aesthetics begin to dominate. If the intended application is to prove a theory, the primary consideration is accuracy. If the intended application is to educate, accuracy need only be relative, providing the audience clearly understands the material being presented. In the case of visualizations made purely for entertainment, aesthetics becomes the sole concern and it is up to the creator of the work to determine how accurate the images will be. Digital visual effects technology has reached a point that, given enough time and resources, no sacrifices need to be made to satisfy both accuracy and aesthetic concerns. As mentioned before, better visualizations can lead to more concise theories about the nature of the universe. For example, to answer the question of the origin of the earth’s moon, scientists generated computer models to test various possibilities. One specific model not only resulted in the creation of a 7 Kallick-Wakker, Science Icons, P. 310 8 single moon, but also accurately predicted the size and motion that is observed today, suggesting a very strong probability that the moon was formed by the impact of an object roughly the size of Mars.I Figure 9 and DVD chapter 2 show the actual computer model generated during this experiment. Technology has reached a point where the standard tools used by the entertainment industry are able to produce many of the same results that are seen from the computer models used by the major scientific facilities, such as NASA’s Jet Propulsion Laboratory. The primary difference between visual effects technology and the technology used by scientists is the intended application. The underlying mathematics and physics are fundamentally quite similar. A visual effects artist can duplicate the results of the scientific visualization while applying an aesthetic quality to generate more interest and understanding in the general populous. Visualization serves to inspire as well as educate, so aesthetics cannot be completely discounted as merely entertainment value. Visualizations For the visual portion of this thesis, the birth of a star is represented in a complete, fully rendered 3D visual effects animation. The intended audience is the general public, so the overall aesthetics are the primary concern. Given that consideration, the goal is to be as accurate as possible while still delivering a compelling and exciting piece, thus demonstrating that the use of visual effects can be used to educate, inform and entertain. The technology used will be some 9 of the most advanced software available to the public and the intent is to prove that accuracy and aesthetics can coexist in the same presentation in a comprehensive and entertaining format. Stellar formation represents an example of the three primary limitations that can be bridged through the use of visual effects. The majority of light and energy produced during stellar formation is invisible to the naked eye. The timescale, physical size and distance from earth are all effectively represented through the visual effects used. These aspects of stellar formation are best represented in this format. The basis for the simulation starts with the science as the outline and basic script. A simple early version was visualized to be sure that the events to be shown were as accurate as possible. Once that had been achieved, the remaining work was entirely centered on aesthetics. This is where the visual effects artist becomes truly valuable. The effectiveness of the visualization is tightly bound to the excitement and interest that the images evoke. Even with proper science, if the aesthetics fall short, the visualization would fail in one of its primary goals. Conclusion As visual effects capabilities increase, the gap between science and entertainment is being drawn shut. Visualizations can be both accurate and aesthetically compelling without sacrificing the integrity of the data that is used as the starting point of the visualization. The challenge is to create these 10 visualizations so that they can be easily understood by the intended audience while maintaining their scientific validity. Scientific visualization allows the artist to create beautiful imagery that both entertains and educates the audience. Visualizing invisible phenomena brings together abstract artistry with scientific data. The ever improving capabilities of visual effects artists bring art and science closer together. By bridging the gap between the visible universe and the elements and forces that define it, visual effects has become a vital tool in expanding the human capability to understand the complete universe. Figure 1 – celestial map Figure 2 – islamicate celestial globe C Figure 3 - astrolabe D Figure 4 - orrery E Figure 5 – EM spectrum F Figure 6 – EGG Nebula – false color G Figure 7 – DVD 1 – black hole visualized H Figure 8 – dark matter breakdown I Figure 9 – birth of moon still and DVD chapter 2 A B