Download It is well documented how technological advancements have

“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, which 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
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COSMOS Episode 1
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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.2
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
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Reference to celestial globes and their inversion thingy
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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. 3 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.
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Mapping of the Heavens, p. 101
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4. Space travel is limited and the physical scale of the universe makes direct
observation of any celestial event or phenomena 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)4 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
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NASA source
5
Phenomena such as black holes emit no light at all5, making them
essentially invisible by definition. They are visualized by observing their effect on
the objects around them and how light is altered by their presence. Extra solar
planets – planets that orbit stars other than the sun – are obscured by the glare
of the stars they orbit. They can be detected 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. Various methods
can adequately represent these phenomena, but through the visual effects
techniques of advanced 3D animation and the realism of the images generated,
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,”6 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
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Except for the occasional gamma ray bursts that shoot out from the center of the black hole
during times when they are feeding.
6 Dark Matter
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complete 3D model can then be extrapolated from these three images
representing the approximate location of dark-matter in the universe.H <image of
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 miles.7
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 at once. Cheating
the sizes or animating a virtual camera through the solar system would be the
only way to experience the 3 billion, 720 million mile 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,’8 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 3D models, events, such as the beginning
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http://www.umpi.maine.edu/info/nmms/solar/
COSMOS Disk 1?
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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.
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. 9
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 either case, comprehension
of the material presented must be take precedence and any compromises on
accuracy should be made in pursuit of this ultimate goal. 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.
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Kallick-Wakker, Science Icons, P. 310
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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
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 in an effort to generate more interest and understanding.
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
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consideration, the goal is to be as accurate as possible while still delivering a
compelling and exciting piece, thus demonstrating how visual effects can be
used to educate, inform and entertain. The technology used is some 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 four 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 time frame of
these events as well as scale and distance can be manipulated in a direct and
visual method without the need for analogy.
Scientific research serves as the backbone of the visualization, providing
the basic script for the animation. 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.
The false-color technique demonstrated, while being based upon solid
scientific methods, was achieved entirely through manipulating the lighting and
colors of the objects being animated. This is a perfect example of the use of the
science as a launching point, while not using any real data in the visualization
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except as references for the final images.
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
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 and the ever improving capabilities of visual effects technology helps to
bring art and science closer together. By bridging the gap between the visible
universe and the elements and forces that define it, the use of visual effects in
scientific visualization 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