samedi 1 novembre 2014

Creating Life on a Gas Giant - On "Hunters, Floaters, Sinkers" from Cosmos

Posted by Adolf Schaller
2013/11/02 21:29 UTC

Cosmos with Cosmos is a weekly series that encourages people to get together and watch Cosmos with a cosmo(politan) or drink of your choice. We're posting weekly episode recaps and discussion through February of 2014. This series is made possible by members of the Planetary Society. If you like what you're reading, please consider joining the Society or donating $10 to help support projects like this in the future. To learn more about this series and find out how to watch Cosmos, see our introduction.

This special post is from Adolf Schaller, the creator of the painting shown below which was featured heavily in Cosmos, Episode 2, "One Voice in the Cosmic Fugue." He was kind enough to share the intense experience of creating this painting for the series back in the late 1970s.
-Casey Dreier

Hunters, Floaters, and Sinkers
Adolf Schaller
Hunters, Floaters, and Sinkers
This painting speculates about possible forms of life on a Jupiter-like gas giant. Airbrushed water-based acrylic. 90 x 120 in (7.5 x 10 ft).
Dimensions: 90 x 120 inches (7.5 x 10 feet)
Medium: Airbrushed water-based acrylic.
Construction: The HFS mural consisted of nine 30 x 40-inch illustration board panels mounted on a plywood backing. The 30 x 40-inch boards were individually worked as separate panels before mounting using a high-quality rubber cement the day before the scheduled shooting. This operation included the application of a special tape and finishing touches to conceal the seams between the panels for the sequence shooting and photography for the book.
Image scale: 1 degree of arc : 1 inch. Its angular dimensions were thus a very wide-angle 90 x 120 degree view. The choice vantage point for a viewer appreciating the entire scene was directly over the center panel some 60 inches from the surface at that point. However, no attempt was made to introduce the distortion which would accrue from mapping a wide-angle area onto a flat surface. This was done in order to permit the camera to zoom in and pan, 'truck' or travel across any region of the painting without encountering any local distortions.
In September of 1978 I received a phone call from Jon Lomberg and Carl Sagan asking me if I would be interested in working on their upcoming PBS science series, "Cosmos". Without hesitation I said yes. They asked me about working on several subjects, but one in particular held a special significance for Carl, and he was keen to see the concept treated with as much realism and scientific accuracy as possible, as well as investing it with an aesthetic that evoked a sense of wonder. He wanted it to excite the imagination, to plausibly suggest what might be within the realm of natural possibility. I shared his enthusiasm for the topic; fortunately, I had good long head start on what would become an unexpectedly daunting and difficult challenge.
It just so happened that I had been producing a series of increasingly large paintings depicting the atmospheric environments of Jovian-class or gas-giant planets - panoramic cloudscapes - for quite a number of years previously, with the intention of eventually creating a series based on hypothetical organisms and even whole ecosystems which could conceivably evolve in such habitats. These early studies included illustrations which appeared in Astronomy magazine and educational slide sets produced by Encyclopedia Britannica (from 1974-1976), Starlog and Future-Life magazines (in particular, a scene depicting a balloon probe afloat above the cloudtops of Jupiter's Great Red Spot (1977), and a 30 x 40-inch Jupiter cloudscape depicting another balloon probe I had donated to the Flandrau Planetarium in Tucson in 1977-1978.
My principle sources of inspiration came seven years earlier. On one of my regular weekend visits to my favorite library back in 1971, I came across a new arrival in the science section: a copy of the book, "Intelligent Life in the Universe", by Iosif Shklovskii as expanded by Carl Sagan, published in 1968. I was 15 at the time, and that book completely absorbed me. Their description of a biosphere entirely suspended within and supported by an atmospheric environment was my first exposure to the concept. By the time I came across Arthur C. Clarke's 1972 short story, "A Meeting with Medusa" not long after my reading of Carl's Cosmic Connection in late 1973, I was enchanted by the concept. A burgeoning ecosystem of diverse creatures inhabiting the clouds of gas-giant planets became a preoccupation, stimulating my imagination in many detailed conceptual drawings and cloudscape studies.
I had by then already developed a serious interest in astronomy and physics with the goal of obtaining a degree, but reading this book (not long after studying Darwin's "On the Origin of Species", and Sagan's "The Cosmic Connection" later on in 1973) had a powerful influence on my thinking. It gathered my varied astrophysical interests and welded them together within the context of life: the nucleosynthesis of heavy elements, biogenic conditions in the interstellar medium, planetary formation and environments conducive to prebiotic chemistry, the establishment of microbial organisms and subsequent evolution and potential elaboration of complex multicellular organisms, ecosystems, societies, intelligence, technological civilizations, and so on. I studied everything I could get my hands on dealing with the subject. I began producing paintings and was immediately published. As it transpired, with all of the commissions I soon acquired, I suddenly found myself embarked on an early professional career as an astronomical artist.
I had also begun to train myself in the use of airbrushes to more easily and effectively accomplish the delicate details and appearance of clouds with quick-drying water-based acrylic paints. Since the age of 8 I had been an avid sky-watcher, a student of meteorology as well as an amateur astronomer. I had been fascinated by clouds for as long as I can remember. (My very earliest memory is of a cumulus-filled sky brightly back-illuminated by a high sun, over a wide tree-lined park; checking with my mother, I believe the observation occurred from a baby buggy my mom was pushing me along in as we strolled along a walk lining a lake shore park on the North Side of Chicago in the Summer of 1957 when I was perhaps 16 months old. It is an extremely vivid memory indelibly etched in my mind...I have even toyed with reconstructing that scene. I might attempt it one day, but it makes me nervous: it suggests an end to memory).
In any case, I had amassed a large collection of cloud photographs for my personal reference years before I had any intention of painting clouds. In 1974 I discovered the venerable Paasche model AB extra fine-line airbrush, an airbrush whose unique mechanical design had not significantly changed since the 1930's and was used for photo-retouching and by artists working on Walt Disney's early classic animated films including 'Fantasia'. This unit became my principle tool in the creation of most of my paintings, and it was the tool I introduced to all of the members of the team of the Cosmos Artists (as we were known) in order to facilitate a uniform consistency in the painted artwork for the visual effects which we were to prepare.
A
©Adolf Schaller
A "Floater" from Cosmos, Episode 2
Part of the larger mural, "Hunters, Floaters, and Sinkers" painted for the series.
Late that month of September, 1978, I was asked to immediately begin preparing preliminary concept drawings for what would become HFS while I was still at home in suburban Chicago. (At the same time I was also asked to begin painting a sequence consisting of four 15 x 20-inch panels depicting the final stages of our Sun's life, named by the title I gave to the first painting in the sequence, "The Last Perfect Day", which Carl subsequently altered slightly to, "The Last Good Day". That first painting was the very first of thousands of separate pieces of artwork I would contribute to the show over the better part of a year - from conventional paintings and artwork painted on flat acetate sheets for multiplane animation fx to tabletop models, planetary globes, asteroids and other models).
By the time I arrived in Los Angeles on February 13, 1979 to join the team of Cosmos Artists and work on the production of the visual effects, I had completed many dozens of preliminary concept drawings of the basic design of the HFS cloudscape environment, along with about a hundred conceptual designs for a variety of species of the three principle types which constituted the hypothetical biosphere and its ecological system: Hunters, Floaters and Sinkers - creatures with diverse shapes and anatomies, aerodynamic and buoyancy properties, propulsion mechanisms, feeding modes, social and navigation or migratory behaviors, communication, reproductive and defense and even stealth strategies, and more, that would not only fit them for life within a global atmospheric habitat, depending on conditions at various altitudes and within clouds of various composition, as well as the other dynamic aspects of weather, but also provide the basis for local or close-range interaction with other individuals of the same or different species, either in encountering those of their own kind (for reproductive purposes, or to maintain mutual proximity in gregarious social collections, for example), in encountering potential prey (Floaters grazed on diminutive but abundant Sinkers, while Hunters ambushed Sinkers for their stores of purified hydrogen as well as for nutrition), or encountered potential predators (both Floaters and Hunters could evolve elaborate defense strategies against attack by other Hunters). Carl's early speculations on Jovian atmosphere life in the 1960s had evolved and he eventually worked out the basic hunters, floaters and sinkers ecosystem which he described in a paper with Ed Salpeter: "Particles, Environments, and Possible Ecologies in the Jovian Atmosphere", which appeared in The Astrophysical Journal, Supplement Series in late 1975. Meanwhile I had been exploring the wide range of potential planetary habitats and designing a great many life-forms in the fleshed-out detail necessary for illustration, that could conceivably evolve and flourish within habitable environments, including Jovian-type atmospheres.
As I already mentioned, I had the benefit of a decent head start: I had been studying the range of potential conditions of gas giant atmospheres, considering those environments as potential habitats supporting hypothetical biological communities for years before I was called to work on Cosmos, and I had already composed a number of cloudscapes that prefigured HFS. In fact, much of the basic cloudscape is derived from the painting I donated to the Flandrau Planetarium in the spring of 1978, a work I had started on nearly 2 years before I commenced work on Cosmos that fall.
I began work on the main Cosmos VFX within several hours of my arrival. I was whisked from LAX to KCET-TV, which is located at the juncture of Hollywood and Sunset boulevards, stood around the offices for a while waiting on another team member, then off we went to the fx studio the show had contracted to perform the main fx, called Motion Pictures Incorporated (MPI) located over the Hollywood hills in Burbank to the north. The Cosmos Artists residence came to be called 'the Artists Apartment', which was actually a rented 3-bedroom house located in a relatively quiet residential neighborhood several blocks east and within walking distance of the KCET offices. We outfitted the house as an artist's studio, each of us working in their own bedrooms, or collectively in the living room/dining room on bigger projects like the large 4-foot diameter Earth globes - a surface globe prepared by Don Davis on which several of us pitched in on to help, and a separate 'cloud globe' of the same size that was my responsibility. The trip between the house to MPI in Burbank was our daily commute. That first night, returning from Burbank, and after that exhausting day that began early that morning in Chicago, I began work on HFS by preparing the first of what I thought would total at least three, but not exceed five 30x40-inch panels.
A Lazy Herd of Floaters
©Adolf Schaller
A Lazy Herd of Floaters
An updated digital restoration by Adolf Schaller of detail in his original Hunters, Floaters, Sinkers mural which appeared on Cosmos, Episode 2, which speculates about life in the atmosphere of a gas-giant planet.
That was to change drastically within the next month. The middle three panels covered the panorama centered along the horizon. I thought at first this might be sufficient, but I found that there would be many opportunities to explore the cloudscape far beneath and high above our apparent position (which I had calibrated by cloud type and other cues suggesting that the viewer was located at about the 1 bar level, assuming ideal smooth and laminar pressure gradient unaffected by weather). I had arranged for a wide-angle view with a scale of 1 Degree of arc to the inch.
It was an extremely exciting time for us: one must keep in mind this was just weeks away from the first of the Voyager flybys of Jupiter that March, and we all marveled at the awesome images Voyager had been returning of those incredible cream-in-coffee clouds with ever-increasing resolution. I was especially keen on studying them to gain some insights I could transfer into the painting. At the same time, I was preparing an accurately oblate 18-inch-diameter Jupiter model for several vfx sequences, and Voyager image prints made available to the press by JPL were indispensable references. Not every image Voyager returned was printed, however. I therefore petitioned to spend the night of closest approach at JPL so that I could study the raw images as they were displayed on the monitors.
As an aside, I should mention that we had visited JPL on several previous occasions to see Jim Blinn, who had created astonishing computer simulations of the Voyager flybys and who would be contributing a number of those along with other sequences to the show. Jim's groundbreaking work pioneered the digital fx revolution everyone enjoys in the motion picture industry today.
The computers he had at his disposal at JPL were costly, huge and slow by today's standards - it took many days for his setup to render sequences of a few minutes length. But the results were gorgeous and mesmerizing. I knew that I was seeing the future in his lab, but I never dreamed then that it would arrive as soon as it has and with such an astonishing boost of capacity and speed. Jim insisted he could never match the complex effects we were performing through traditional animation methods and camera moves on models and artwork, but it was certainly obvious to me that none of us could replicate the accuracy of the motions and trajectory of that little virtual Voyager I saw pirouetting on his monitors. Jim's sequences had the look of authenticity which was notoriously difficult to achieve via traditional vfx methods.
In any case, it was on one of those visits that I noticed there were half a dozen large monitors set up in an out of the way corner of the lobby to the von Karman auditorium, where members of the press congregated, and it occurred to me to be a perfect place to unobtrusively watch during the spacecraft's flyby. But it turned out that it was a surprisingly tough sell - nobody thought that an artist required any such referential input. This puzzling and exasperating attitude introduced me to a commonly held view amongst scientists and producers alike that art somehow springs spontaneously out of uninformed or unstimulated gray matter.
I was increasingly anxious as the flyby approached to have my request granted, so I asked to meet with Carl privately over at the Artist's Apartment. I had been enforcing a strict policy of keeping my work on the HFS panels under quarantine: nobody could see them except Carl and a few confidants on the team. The reason for this was to avoid unnecessary disruptions and preserve my concentration against the well-intentioned suggestions and advice of people. (I liken the phenomenon to rearranging the furniture physically without being able to visualize whether a given configuration is optimum: if it was up to some, a given project would change course so often it would never get done. The execution of a work is not a time to get distracted by experiment - that's supposed to be settled with the preliminary conceptual studies).
To my delight, I got my chance to plead my case: Carl accepted my invitation to stop by about a week before the flyby, and I displayed the three central panels arrayed along the horizon, propped up against the wall side-by-side, to show him how it was progressing. By that time I had finished most of the areas within 8 to 16 inches of the horizon centerline and had roughed out the rest of the cloudscape throughout the remaining area of the panels.
I was very gratified at Carl's reaction to it - he spent several long silent minutes in front of the panels, slowly shifting from one side to the other, his eyes scanning the detail along the horizon and the structures I had established above and below it. When he began to speak he grew really excited and I fielded his questions the best I could. I showed him what I had begun to prepare in two additional panels that could be positioned at the upper left and lower right corners to give the camera a view of regions close up, far down below and high overhead, where much of the details of the organisms that I had sketched could be established. I ventured the possibility of adding two more panels beneath and above the center panel as well, reiterated that the amount of work involved in covering so much area on these boards with a uniform level of detail was very time-consuming and laborious, and that the schedule may not permit me to get that far to finish those. He stood in front of the scene and stepped back a few paces as if to take in the entire scene in his imagination, while pondering silently for another full minute. Then he said, "Let's fill out the whole thing and make it a full nine panels."
My initial elation at his reaction to the painting turned to stark terror. I remember a very unpleasant queasy feeling in the pit of my stomach as my mind automatically calculated the area involved and I guess I was at a momentary loss for words. (10,800 square inches - 75 square feet of area to cover with millimeter resolution detail - it was petrifying). I finally managed to croak out something about how I didn't have enough time to devote to something that large and keep up my responsibilities with the rest of the effects. He simply said "Don't worry, we'll find a way", and just like that the matter was decided.
A Hunter
©Adolf Schaller
A Hunter
A speculative hunter animal evolved in the atmosphere of a gas-giant planet. Developed for Cosmos, Episode 2.
I must have been showing my shock, because he cheerfully changed the subject onto my request to go to JPL for the Voyager flyby. He reiterated the fact that he didn't want HFS to reflect an explicit association with Jupiter. I said I understood that perfectly that it was to be a portrayal of a hypothetical but generic gas giant world. But it was nevertheless an important opportunity to gain an insight into gas giant atmospheres. After all, Jupiter is a gas giant planet - and nobody had ever seen what those clouds really look like at the sub-km resolution that Voyager would soon return. I considered it vitally important to the painting, and I said so. It really is that important if an artist is expected to realize a visualization with maximum realism and accuracy. (It is generally under-appreciated that the task of portrayal compels artists to explicitly define the subject - we can't always enjoy the luxury of ambiguity in dealing with our subjects). I added that those monitors around the side of the auditorium lobby were all I wanted to be able to sit in front of so I could sketch and take notes. He smiled and nodded and said, "Good! I'll arrange it!" And with that our meeting ended.
So I was there at JPL during the flyby. As full of people as the auditorium was, that corner was deserted and eerily quiet all that night. But I didn't pay much attention to that. My eyes and attention were glued to the monitors and I was soaking in every image that came up. It was a mesmerizing night; it was as if my mind was transported to the spacecraft. The memory of it often returns to haunt me in quiet moments to this day...and, yes, it contributed a great deal - in some places crucially - to HFS. The main insight that was impressed on me that night was the prevalence of vortices and eddies, as especially evident in the turbulent region downstream of the GRS, and in the interactions between ovals and along the boundaries between bands and zones, right down to the limit of resolution. In suitably turbulent regions, vortices and eddies were evident down to the limit of resolution. That was the single most important insight I derived. It suggests the preponderance of vortices below mesocyclone scale, and the vigorous convection evident in many regions is more than sufficient implication: Jupiter and many other gas giant worlds with deep convective atmospheres must be full of tornadoes at every scale from the monstrous down to whirlwinds.
One consequence of the insight on the mural appeared in the form of a large cyclone reddened by a high population density of "Sinkers" (the analogue of plankton in earth's oceans) concentrated there to exploit nutrients updrafted from the depths below. Sinkers are comparatively tiny, ranging from microbial to large party balloons in size (many of the larger examples ranging upwards toward weather-balloon-size being newborn and juvenile Floaters and Hunters), so we only see the reddish coloration of the vortex from a distance of a few hundred kilometers, but their presence is also indicated by what they have attracted: a congregation of "Floaters" lazily grazing on them or giving birth to them in great numbers over the spot, in a vaguely helical pattern resembling the molecule of life. Strong convection and turbulence in Jovian atmospheres is often cited as a detriment to the evolution of organisms within them, yet such cyclones can conceivably play a crucially important role in concentrating nutrients and provide stable refuges.
I also added a more conventionally recognizable 'twister' emerging out from the ceiling of the canopy at the upper left because I wanted to give the camera a chance to come across one unobstructed funnel, and there was no other convenient place to place it. Its bothered me because strong vertical convection of the sort typically required to form them would normally not be taking place within a laminar stratus plume of that kind. It was placed there for the convenience of the shoot: it wouldn't be very noticeable in the long shots, but only when the camera panned over the region at close quarters, making the ceiling resemble the base of a convective cell.
I spent an estimated average of 4 hours of our typical 14-hour day on it every day over the following 7 or 8 months. Some days it was difficult to find a half hour for it - on those days I was too exhausted from pressing duties elsewhere in the fx production. To my dismay that workload had increased apace with the added challenge of filling out nine entire panels for HFS. The docket was exhausting.
I don't recall what month HFS was finally ready for the shoot. (I was far too exhausted by then to notice and, frankly, the Southern California climate doesn't provide one who grew up in the upper Midwest and used to annual snowfall enough cues to impress what season it might be...but I think it had neared the end of 1979 by the time I had finished HFS for the shoot). I do remember that the final push was a 2-week period staying permanently awake, like a zombie. It's like sleepwalking, except that though you know (or think you know) you are awake and your eyes are open, you are in a constant dreaming state. It was dreadful. I don't remember anything I painted during those closing weeks except for flashes of the final touch-ups on the stage at KCET. But I do remember it took me a very long time to recover.
The sequence was shot with director Adrian Malone having Carl physically walking, speaking and gesturing in front of it. Adrian meticulously choreographed the camera moves that panned over and zoomed into sections of the mural to show some of the detail in it with Carl's narrative voice-over. I was not present at the shoot: I was passed out in bed in our new apartment in Santa Monica, not remembering how I got there. I think I was out for almost 3 days. After HFS there were odds and ends as the work load rapidly eased off. It was the last major artwork or fx sequence of the production. It was rescheduled that way to help give me all the time possible (I'm pretty sure, under Carl's instructions) but it was The Monster among monsters.
Later the next year after Cosmos had aired, I and my fellow vfx colleagues (belonging to both the Cosmos Artists team and the crew who worked at Magicam noteworthy for their excellent Alexandrian Library and the Cosmic Calendar sequences) were awarded the 1980 Prime-Time Emmy Award for Outstanding Individual Achievement, Creative Technical Crafts. We assembled up on the stage and accepted the award to a long ovation. To my consternation my colleagues kept ushering me forward toward the dais to make the first comments. I was reluctant - I'm not good at speaking, let alone publicly. All I could manage was to thank my parents and a special friend for their support. But the one person who inspired me to explore the possibilities more than any other was Carl Sagan.
Source : http://www.planetary.org/blogs/guest-blogs/2013/20131023-on-hunters-floaters-and-sinkers-from-cosmos.html

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