This page, from 2001, is presented as a souvenir. The Observatory will reopen with new exhibits in 2005. The renovated Observatory will also feature a full-sky laser projection system to project bright and colorful moving visuals on the dome.

The Lawn

As you look at the Observatory, you’ll see three large copper domes. The one on the right (west) houses the triple-beam solar telescope; the one on the left (east) houses the 12-inch Zeiss refracting telescope; the largest dome (at center) houses the planetarium theater. The cupola (front center) holds the pendulum over the Main Rotunda. Access to the roof and the Refracting Telescope is by way of the stairway on either side of the building.

Note the romantic art deco style of architecture of the building, which was constructed in 1933-1935.

On the west edge of the lawn is a memorial to James Dean in the form of a bronze bust. Major segments of Rebel Without a Cause were filmed at the Observatory, as have been many motion pictures since. The Astronomers Monument honors six of the greatest astronomers of all time. They are Hipparchus (?-125 B.C.), Copernicus (1473-1543), Galileo (1564-1642), Kepler (1571-1630), Newton (1642-1727) and Herschel (1738-1822). Near the Monument a radio antenna receives signals from weather satellites for display in the museum.

At the base of the Monument is the sundial. The fundamental units of time are set by the cycles in the sky. The sundial is a link between the sky and our need to measure time, and it’s actually a model of the apparent movement of the sun. The sundial's thick round bar represents the celestial equator, which is the projection of the earth's equator into space. The main axis, a metal rod, lies parallel to the earth's axis of rotation. The sun is south of the celestial equator between September 22 and March 21, and during those months the shadow falls on the north part of the time indicator. The sundial doesn’t work on the first days of spring or autumn. As our sun crosses the celestial equator, the shadow of the thick bar falls on and hides the time scale.

Hall of Science

Main Rotunda
Upon entering the building your attention goes first to the Foucault Pendulum. The pendulum demonstrates that the earth rotates. The 240-lb brass ball, which hangs by a wire 40 feet long, swings in a constant direction while the earth turns beneath it. The pendulum is supported by a bearing that doesn't turn the pendulum as the building rotates with the earth. A ring magnet at the bearing gives a little tug on each swing of the pendulum to keep the pendulum in motion. It is set up by the staff each morning and runs all day. It slowly comes to a stop after the power is turned off at night.

Look up to see the famous Hugo Ballin Murals, completed in 1934. Medieval cathedrals told stories in stone, and these murals tell the story of science in paint. On the ceiling are Atlas, the four winds and the signs of the zodiac. Other figures include the planets as mythological gods and a comet. The eight panels show highlights of astronomy, aeronautics, navigation, civil engineering, metallurgy and electricity, time, geology and biology, and mathematics and physics.

South Gallery
The South Gallery is between the Main Rotunda and the entrance to the planetarium theater. The general theme is planets.
You’ll notice the Gravity Well first. Its shape reproduces the gravitational effect the sun has on the planets (or a planet on its moons). The well has a steeper curvature (“stronger gravity”) near the center, which causes objects to speed up as they approach the center. In the gravity well, friction with the surface causes the steel balls to slow down and eventually fall in; in space there is so little friction that the planets do not move significantly closer to the sun during the lifetime of the solar system.

The Astroscreen is a large rear-projection screen with a video projector behind it. It promotes the current public planetarium show. Large color transparencies surround the Astroscreen. They are some of the most spectacular photographs ever taken of the planets and their satellites, and most were taken by spacecraft. Scale models of the planets lie opposite the Astroscreen.

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