Morrison Star Projector
Planetarium Closure Marks End of an Era
By J. M. Ryan
Looking up, they see piercing stars amid ebon splendor. Mars shines in Aquarius, and Saturn in Gemini. The Milky Way, arching overhead, elicits murmurs of awe. Dark, cozy silence wraps warm about them like a blanket.
A fireball streaks toward the east, and a pulsing melodic swell of music greets the sunrise. Some clap in rhythmic harmony, then more, then the whole audience. In a minute, it is over. With the 'Good Morning' greeting from the lecturer, they applaud, and join nearly 10 million others who've witnessed, over the past fifty-one years, a starshow at Morrison Planetarium.
As 'sunrise' ends, the theatre brightens, and the platform floodlights cast primary colors upon the gleaming centerpiece, the black star projector poised over the center platform, suspended across twin tripods. Resembling nothing so much as an enormous ant, the massive machine, over 13 feet long, almost 5 feet thick, and weighing a ponderous 5,000 pounds, dominates the star theatre.
It was named the Academy Projector, after the venerable California Academy of Sciences, the San Francisco-based natural history institution that traces its origins back to the days of the Gold Rush. The Morrison instrument was designed and constructed by Academy staff and volunteers between 1947 and 1951, making it the first major planetarium projector ever built in the United States. The planetarium first opened to the public on November 8th, 1952.
While most school-sized planetarium projectors have been manufactured in the U.S., nearly all the large city-sized projectors are from Japan, or from Germany where the type was invented by the Carl Zeiss Optical Company in 1923. Following World War II, the bomb- damaged Zeiss Works, then the world's only manufacturer, lay in the Soviet zone of partitioned Germany. The only way San Francisco was going to have a star projector was for those at the Academy to build it themselves. And they built the best ever seen. Even now, it remains one of a kind, unique in the world.
During the Second World War, the Academy joined a nationwide volunteer effort to support the Allied cause. It's staff and volunteers fabricated some 10,000 optical parts, and repaired 6,000 pairs of binoculars for the Navy. At war's end, the War Department gave the Academy access to its inventory of surplus parts.
The Academy Projector was built using a number of robust military-surplus components which at least partially account for its exceptional reliability, particularly the main bearings used to support the heavy starglobes, designed originally for tank turrets. It also contains miles of wiring, and dozens of fine World War II Aero Ektar and Aero Tessar lenses, formerly used for aerial surveillance and photography.
Few machines have been able to operate daily for more than fifty years without having had nearly all parts replaced, sometimes several times. Yet, except for such limited life components as bulbs and switches, the Academy Projector is still, amazingly, nearly all original. After over half-a-century in operation, its durability is nothing short of legendary.
The Morrison star projector produces a starry sky astonishing in its realism, even when compared with modern, high-tech successors. The natural appearance and image quality of the starpoints stem from the use of irregular apertures which induces an optical illusion of twinkling. Although that effect has been artificially duplicated in newer machines, many believe that it has never been made more realistic.
The irregular openings were created by depositing a thin aluminum coating over carborundum grains that were precisely placed on flat condenser lenses. The grains were painstakingly sized to approximate the stellar magnitudes, or brightnesses. The grain size selection, their cautious one-by-one placement, and some extensive reprocessing that followed, involved many months of work. In sum, it was a tedious procedure that no one would ever use again, but it resulted in perhaps the most natural-looking projected sky ever created.
The star projector sits, with center of mass almost ten feet above the audience, in the middle of the star theatre 65 feet across, vaulted by a dome of white perforated aluminum rising higher than a four-story building. The salon-like room, warm and welcoming, features comfortable chairs, subdued lighting, and wafting music. The plaques on the walls, the glass case with archival displays, the remnant of the original black console with its red and black toggle switches, and the spotlighted bust of Alexander Morrison, convey a sense of history. Metal cutouts, artistically shaped as buildings, bridges, and landmarks form a familiar San Francisco skyline-in-silhouette around the periphery, where the arching dome meets the top of the circumscribing wall.
In the science gallery, beyond the western wall of the theatre, the gleaming brass teardrop that is the Foucault Pendulum swings endlessly to and fro across a fenced circular pit, demonstrating the relentless turning of the Earth. Entranced visitors stand or lean for long minutes contemplating the ceaseless motion as they anticipate the periodic toppling of the vertical pegs, each delicately stood on end at its respective mark.
Unfortunately, this exquisite venue and the remarkable machine at its heart will serve the public only through December 31st of this year. Anyone wishing to visit the historic planetarium and its outstanding artifacts, or to witness the fine, original shows still produced at Morrison, a rarity in today's world of standardized product, has just until year's end to do so.
After that, it's uncertain where, when, or even if the star projector, the skyline, and the pendulum will again be seen on public display. The Academy is right now in the process of renewing itself as a modern, state-of-the-art facility for the 21st century. It's on the verge of relocating elements of its museum and aquarium to an interim location on Howard Street, while it demolishes, then rebuilds its 75-year-old home in Golden Gate Park.
Morrison will also be rebuilt, in the modern style of planetaria today. It will feature sloped theatre-style seating, with all chairs facing the same direction at the same time. The dome will arch down in front of the audience, rather than loft above it.
The new configuration is not only to spare the necks of the visitors, but to enable complementary use of the dome as a life-scale movie screen. It will be able to present not just traditional starshows, but all-sky digital immersive video, including space-transit effects that will simulate cruising through the Universe aboard a starship. Since the audience essentially sits up inside the dome, it will be over 80 feet across, about as large as any American planetarium, which will also enhance the realism. And, of course, the computerized laser and multimedia effects are to be state-of-the-art.
That new complex, though, is not slated to open to the public until mid-2008. During the closure, the word is that Morrison will continue public outreach activities using inflatable domes. It will also be offering lectures in borrowed or shared venues.
However, there has been no word concerning the preservation, display, or transfer of the projector and the other historic fixtures. Architectural models and mock-ups of the planned new Golden Gate Park facility are on display in the gallery by the Foucault Pendulum but, at present, they show no space allocation to display these historic artifacts. Though it has made no public comment, the Academy is said to be seeking a home where the projector, at least, can be operated or displayed. It might appreciate knowing the thoughts and preferences of its members, patrons, and interested advocates in this regard.
The citizens of San Francisco and the surrounding region share a vested interest in the outcome. Although the largest funding grant came from the estate of May Treat Morrison, to honor her husband, Alexander, the planetarium was, by no means, solely a private or institutional project. Its acquisition involved a citywide promotional campaign and an abundance of small citizen contributions from around the region. Children in schools famously donated their pennies to aid its completion. Great civic action and pride were involved, on many levels. The planetarium was a landmark exercise in the power of citizen involvement and initiative. And it has, for decades, been a favorite field trip destination for hundreds of schools from around the region and across the state.
Furthermore, the star projector was one of the last, if not the last, triumphal technical achievements in San Francisco between the 1850's and the 1950's, before the era of high- tech. During that hundred-year span, San Francisco become the first real city west of the Mississippi as well as the gateway to the Gold Rush, the first event in world history that presented the prospect of real wealth to common people. California achieved statehood, the transcontinental railroad was built, cable car technology mastered the hills, and the 1906 earthquake and fire occurred, followed by the City's recovery and renewal.
Then came the building of Golden Gate Park, the largest man-made urban park in the world, the landmark Pan-American Exposition, the construction of the two mighty bridges, and the city's indispensable support for the World War II effort in the Pacific. That period laid down a history which, for decades, conferred upon San Francisco the proud appellation; 'the City that knows how'. The Academy Projector, the fulfillment of an implausible dream, adds a proud chapter to that history.
Morrison Planetarium also played host to some of the most unusual research ever funded by the U.S. Air Force. In the early 1960's, it was the venue for a study project to determine whether birds employ celestial navigation to guide their migrations. Though an unusual project for a planetarium, it was very much in keeping with the Academy's emphasis on life science, and on phenomena of the natural world.
In retirement, many have suggested that an ideal spot for the star projector would be a place of honor in the new rebuilt Academy, where it would almost certainly be a unique and fascinating magnet to visitors. Some thoughtful suggestions have been offered for ways to display the machine dynamically, featuring movement along its axes, or demonstrating its sky on a portable walk-under dome. A static display, appropriately documented, would also make a meaningful exhibit.
It has been suggested to sell or donate the star projector for use in another planetarium, but there's general agreement among knowledgeable people that it's too large, with projection axes too far off-center, to be used successfully under any dome smaller than the present 65-footer. It's likely that any planetarium with a dome that large will be able to afford a modern projector, and will want one much newer, less massive, more versatile and flexible, using laser, video, CCD and other technologies whose service knowledge base does not shrink with each passing year. It's unlikely that anyone would undertake the trouble, risk, and expense of moving, mounting, and relying upon, so heavy and aged a machine. Plus, it would require a suite of specialized support equipment and facilities for it to function as it does now.
Another idea has been to loan or donate the machine for exhibition at another appropriate museum. But, despite the large collection of museums in and around San Francisco, there appears to be no obvious choice, such as a regional museum of science and industry, although private collections are a possibility. The Smithsonian, too, has been suggested, but it might take a concerted campaign of public support to help the Academy convince those who run the national museum that it would make an appropriate exhibit for the American History, Natural History, or Air and Space unit.
There is a philosophical and emotional downside to the idea of donation or sale. Many in the international planetarium community vest the Academy Projector with a respect and a reverence reserved for no other. Countless thousands of visitors to the planetarium first experienced astronomy under the dark skies of Morrison, some as far back as the 1950's. They remember the projector as a memorable influence in their lives. Many first came with their classes on school field trips. In fact, many admit to feeling almost a familial connection to the great instrument.
The star projector clearly represents one of the Academy's great achievements. No other single exhibit or feature has even come close to educating or entertaining so many people over so long a time. Its reliable service and the excellence of its construction serve as worthy tributes to the leadership, initiative, and industry of the Academy's past.
For those who've known, admired, even loved Morrison Planetarium and its remarkable projector, time is short and opportunity fleeting. Those interested to once again, or even for the first time, enjoy the unique ambience of the star theatre should plan now to visit before final closure on December 31st. The planetarium will present shows every day except Thanksgiving and Christmas.
There is a minimal cost for admission to the planetarium. Most days, there is an admission charge to the Academy, as well as a fee to park in the central plaza. The first Wednesday of each month is Free Wednesday, a day on which admission to the Academy of Sciences is free to all. Parking remains free on the streets adjacent to the museum.
The regular show schedule terminates on Sunday, December 28th. From Monday through Wednesday, December 29th through 31st, both the Academy and the Planetarium will offer a three-day open house, waiving all admission fees. Morrison will feature the live program "The Sky Tonight" eleven times each day, starting every hour on-the-hour from 10 a.m. to 8 p.m. The shows will be timed to allow the opportunity for questions and picture-taking. The Wednesday show beginning at 8 p.m. will be the last. About the writer:
Mr. Ryan is one of those for whom a visit to Morrison Planetarium as a young child in 1953 kindled an abiding interest in astronomy. He has been a lifelong amateur astronomer and astronomy educator, an aerospace researcher and engineer. He has also twice worked for Morrison.