“If all mankind could look through that telescope, it would change the world!”

As a solar energy researcher, of particular novelty and interest to me were the coelostat and solar telescopes at the observatory. According to Encyclopedia Britannica, a ceolostat (Latin for ‘sky-stopper’) is a “device consisting of a flat mirror that is turned slowly by a motor to reflect the Sun continuously into a fixed telescope.” In other words, despite the sun’s heavenly transience, the Griffith ceolostat reflects light onto three instruments within the observatory from which visitors can see the live, stationary images of the sun.

The ceolostat projects into a white light viewer that allows sunspots to be seen. Additionally, there is a spectroscope (my favorite of the solar instruments) that passes sunlight though a series of optics to reveal the sun’s Fraunhoffer absorption lines, exposing which elements are present in the sun’s outer region. Finally, there is a spectrohelioscope, which restricts the view to the hydrogen alpha portion of the spectrum, making the chromosphere visible. In this region of the sun, eruptions from the sun’s surface reveal the turbulent magnetic fields surrounding the sun.

Additional information about the sun and sky are posted regularly on the Griffith’s sky information page and sky report.

The Griffith Observatory is definitely built for astronomers and not for engineers. My only disappointment was that data relevant to solar engineering is not on display to compliment the various astronomical presentations. For example, data on instantaneous insolation, the real-time coordinates of the sun in the sky, and time-integrated insolation would add an attractive engineering element to the scientific core of these demonstrations.