Exhibits: Hall of the Sky

The Hall of the Sky establishes each person's connection to the primary objects in our sky: the Moon and the Sun. The end of the hall is anchored by one of the largest public solar telescopes in the United States.

Coelostat And Solar Telescopes - Griffith Observatory's three solar telescopes bring the Sun directly to visitors in the west rotunda of the Hall of the Sky. On clear days, each of these telescopes provides a different real-time view of our local star, including sunspots and solar flares. The three beams of sunlight for the telescopes are focused into the rotunda by a triple-mirrored tracking device called a coelostat (Latin for "sky-stopper"), which is located above in the western dome of the building. The solar telescopes operate only during clear daytime hours.

Coelostats are often used in solar observatories where moving small tracking mirrors is preferable to moving large telescopes attached to heavy equipment. Designed by Russell Porter, whose drawings served as the basis for both the 200-inch telescope at Palomar Observatory and Griffith Observatory, the three mirrors of the Observatory's coelostat move continuously during the day to remain focused on the Sun as it appears to move across the sky. The incoming light bounces off one mirror to another and then down through openings in the rotunda ceiling to the telescopes below. The telescopes show a white light image of the Sun, a view through an H-alpha filter (spectrohelioscope), and a solar spectrum (spectroscope). One of the largest and most-visited public solar observatories in the world, Griffith Observatory has enabled millions of people to observe the Sun safely.

The coelostat instrumentation in the dome and three telescopes housed in the rotunda remain essentially unchanged by the renovation and expansion project, other than new motors for the dome, new electrical service, and restoration of the telescope bronze and optics. A new station in the gallery receives live signals from each of the telescopes to provide an equivalent observing experience for those unable to climb the stairs to the rotunda where the telescopes are mounted.

The Active Sun - Recent spacecraft data illustrate the power and dynamics of our Sun.

Our Sun Is a Star - Scaled models and animations show how the proximity of our local star, the Sun, is critical to our lives and helps us study the nature of all stars, the engines of the universe.

Elements
- An elegant, eight-foot high periodic table includes individual boxes and samples and allows visitors to understand how all the elements we know, and which compose us, are made through the birth, life, and death of stars. We are all literally made of material from stars.

West Alcoves - The motions of, and interactions between, the Sun, Earth and Moon affect our daily lives. These fundamental processes are observed primarily with the eye, even if the eye does not fully reveal their nature. In each of the six alcoves featured in this area - Day & Night, Sun and Stars Paths, Seasons, Moon Phases, Tides, and Eclipses - a fundamental process is illustrated using a model and/or video and related captioning. These are concepts about which Observatory visitors often ask, and Guide staff are now able to use these exhibits to illustrate their explanations.