Visitor From Outer Space Set to Arrive For
Morrison Planetarium's 50th Anniversary

Eclipses, Meteor Showers and Comets
Will Mark Planetarium Birthday on November 8, 2002

Sun Expected to Stand Still

SAN FRANCISCO (September 23, 2002) - On November 8, 1952, Delta Aquilae, a star in the constellation Aquila the Eagle, emitted a ray of light that began to race towards earth at 186,000 miles per second - the speed of light. On that same evening, Morrison Planetarium at the California Academy of Sciences in Golden Gate Park opened its doors to visitors for the first planetarium show in San Francisco history. For 50 years, neither one has stopped. This November, the two will meet for the first time, as Delta Aquilae's celestial light ends it 50 year journey and touches down on earth during the celebration of Morrison Planetarium's 50th anniversary.

Planetarium Sky Shows offer visitors visions of 3,800 stars plus comets, meteors and other celestial phenomena like the northern lights. The images are projected onto the 41.5' high, 65' diameter dome of Morrison Planetarium and are accompanied by trained astronomers who give live presentations. Since it opened in 1952 an estimated 9,800,000 people have seen a Morrison Planetarium Sky Show.

"Morrison Planetarium is the only place in San Francisco where the sun stands still at the touch of a button and you can see the night-time sky go through 26,000 years of changes in the course of a 40 minute show," said Dr. Patrick Kociolek, curator and executive director of the California Academy of Sciences. "For nearly 50 years, Bay area residents, school children, tourists and others have leaned back in the chairs of Morrison Planetarium to learn about what may be the oldest science of all: astronomy."

Public Events

To mark the Anniversary, the California Academy of Sciences plans a number of public activities, including a party complete with birthday cake on Saturday, November 9 at 1:30pm. A behind-the-scenes planetarium lecture will be given at 3:30pm and children's activities will run through much of the day.

A special Sky Show, Stars Over San Francisco - Then and Now, showing how the planetarium and our knowledge of the Universe itself have changed since 1952, will run throughout the fall and beyond, along with several other Sky Shows. From September 13 through November 26, 2002, planetarium admission prices will be rolled back to 1952-levels: $0.74 for adults, $0.30 for children.

As part of the anniversary celebration, an evening of Cuban Music under the stars of Morrison Planetarium will take place on October 19, with live music from Orquesta La Moderna Tradicion. In addition, Neighborhood Free Days, which allow San Francisco residents free admission to the Academy and planetarium on particular days according to their home zip code, will help celebrate the Planetarium's 50th birthday. Free Days start October 4 and run through November 17.

History of Morrison Planetarium

When the Planetarium opened in 1952, it was only the seventh large planetarium in the entire United States and the only one that used a star projector designed and built domestically. At its inaugural show, visitors, including the director of a competing planetarium, agreed that the Morrison Planetarium's star projector was the most advanced in the world and created a more realistic vision of the nighttime sky than any other.
Prior to that time, the Carl Zeiss company of Germany had created virtually every star projector in use. But, in the aftermath of World War II, their factory, which was in the Russian Zone of Germany, lay in ruins and there were no plans to revive their star projector business. Faced with this problem, yet determined to have a planetarium, the late Robert C. Miller, Academy Director at the time, declared at a board meeting, "We will build a projector."

Years later he admitted, "That was a pretty rash statement because I had no idea how we would go about it." The Academy achieved its goal by relying on the expertise of one of its paleontologists, Dr. G Dallas Hanna, who had an interest in optics. Using a simple brochure about a Zeiss projector as his guide, Dr. Hanna worked with the Academy's machine shop to create the projector. The shop had acquired optics expertise during World War II, when it had been converted to military use.

One of the first tasks was choosing the stars that the projector would show. Starting with a catalogue of over 33,000 stars, the planetarium staff used a new IBM punch-card computer at the University of California at Berkeley to pick approximately 3,800 of the brightest.

Previously, star projector lenses were made by drilling tiny holes into metal sheets; light projected through the holes became stars. However, the resulting stars were too perfectly round and did not reflect the true look of stars. Instead, using microscopes, a planetarium staffer placed carborundum crystals (some as small as one and one-half one thousandths of an inch) onto glass lenses and then coated the lenses with vaporized aluminum. When the crystals were carefully brushed away they left a series of tiny holes that closely correspond to the shape and position of the 3,800 different stars. Positioning the crystals alone took six months to complete; no one since has replicated the process.

"After nearly five years of hard work, and $140,000, the completed star projector was better balanced and more precise than many Swiss watches," said Steve Craig who began working as a technician in the Planetarium in 1960 and today is its chairman. "That level of precision is pretty amazing, when you consider it weighs some 5000 pounds, stretches for 13 feet, includes 141 optical systems made up of 321 lenses and contains a total of 25,000 individual parts controlled by over 4 miles of wire."

All that, plus a series of motors that allows the star projector to simultaneously rotate horizontally and vertically, allows the star projector to accurately portray the view of 3,800 stars and their changing position in the night sky as the Earth rotates and time passes. The completed projector has been variously described as looking like a two-sided Martian gun or a large mine washed up on shore.

The Planetarium got its start, and its name, from a $200,000 gift from the estate of May T. Morrison, the widow of Alexander Francis Morrison, a prominent San Francisco attorney, for whom the Planetarium is named. Other private donations, including $10,000 in pennies, nickels and dimes collected by San Francisco school children helped pay for the $1,000,000 planetarium and the $140,000 star projector.

The result was a projector that can show the exact position of the stars at any given point in a span of 26,000 years, offering the view from any vantage point on earth. The opening of the new planetarium, with it's American-made projector made national news, coming at a time of growing interest in space exploration, but before NASA launches were common or man had walked on the Moon.

"The most remarkable thing about the star projector is that even though it was built by staff and volunteers with no direct experience of making such a machine, it was the best in the world at the time and is still working well today," said Bing Quock, assistant chairman of Morrison Planetarium and show producer. "We have added computer controls and a few special effects, but the core of our Sky Shows is still the star projector. It works just as well as it always has and is considered a classic of design in the world of astronomy."

Planetariums were so novel in 1952 that some early audience members would call the box office prior to their visit to ask if the evening's show would be cancelled due to fog. They soon learned that the weather is always good for star-gazing inside Morrison Planetarium.


[The California Academy of Sciences, Steinhart Aquarium, Morrison Planetarium and the Academy's logo are registered trademarks of the California Academy of Sciences.]


# # # #