The Gottlieb Transit Corridor

The passage of time and the cycle of the seasons is fundamental knowledge. The Sun’s daily passage (transit) across the north-south line (meridian) and its changing elevation along the north-south arc that bridges the sky (celestial meridian) have been observed by people all over the Earth from prehistoric antiquity. While our world now moves with a precision defined by atomic clocks, the “zero-point” of time remains the transit of the Sun through the meridian, the north-south line that stretches around the globe at a given location on the Earth.

The Gottlieb Transit Corridor is an accurate outdoor public astronomical instrument built below-grade onto the west side of the Observatory. Its form echoes similar instruments from ancient temples and medieval churches, but updates the concept for the 21st century. The instrument has four primary components:

• Meridian line. A bronze meridian line runs down the center of the glass-walled corridor. It is bounded on the north by stairs to the lawn and on the south by a large, black monolith. The line defines the meridian on the ground while the walls of the corridor flank the celestial meridian in the sky. The stairs and banister are angled to the north pole of the sky.
• Foil. Mounted at an angle on the top of the monolith, the foil is a thin, curving metal panel containing a six-inch, long-focal-length lens. As the Sun moves across the sky each day, the lens sharpens the Sun’s light into a spot that moves across the walls and floor of the corridor.
• Meridian arc. Centered at the south end of the corridor, a bronze-faced meridian arc displays the meridian line and is inscribed with month and day markings, seasonal and lunar indicators, and constellation figures. The arc is 18 feet long and 13.5 feet high. Each day at local noon, as the Sun passes, the spot of sunlight moves across the meridian on the 7-inch arc and enables visitors to see how the Sun’s progress is linked to the calendar. In a modern twist, photoelectric sensors embedded in the meridian arc are activated by the transiting spot of sunlight and send a signal to the ecliptic chart.
• Ecliptic chart. On the west side of the corridor, a 22-foot-long stainless steel engraved star chart illustrates the Sun’s annual path through the background stars and the constellations they occupy. When sunlight strikes the photoelectric sensors on the meridian arc, the signal activates LEDs embedded in the ecliptic chart and lights up the stars of the constellation through which the Sun is passing. In this way, the Sun’s light reveals to visitors the unseen sky that is always present, but invisible to our view because the Sun is so bright.

Architecturally beautiful and astronomically revealing, the Gottlieb Transit Corridor is a simple but profound addition to Griffith Observatory’s set of public instruments.

The Team Behind the Gottlieb Transit Corridor

Both scientific and architectural in nature, the Gottlieb Transit Corridor is the product of a dedicated team of experts. Griffith Observatory Director Dr. Ed Krupp originally conceived of and developed the concept for the Transit Corridor as a new astronomical instrument.

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Bruce Bohannan, Ph.D.

Corridor and Instrument Scientist

Dr. Bruce Bohannan provided the scientific guidance for detailed design and development of both the corridor and the instrument components. In 2001, he developed the requirements document and performance standards (updated in 2005) for the corridor and instrument elements and continues to guide development of instrument graphics and content.

Dr. Bohannan graduated from the University of Alberta (B.Sc., chemistry) and the University of California at Los Angeles (M.A. and Ph.D., astronomy). From 1991 to 2002, at Kitt Peak National Observatory, he was operations manager for the mountaintop and project scientist. Earlier at the University of Colorado, he was the director of Sommers-Bausch Observatory and, at times, the Fiske Planetarium. His research centers on observational studies of the evolution of massive stars. Personal pursuits include large-format digital photography and a study of how photography revolutionized 19th-century astronomy.

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Pfeiffer Partners, Inc.

Corridor Architect

Pfeiffer Partners served as the lead architect for the renovation and expansion project. In that role, they worked closely with Dr. Krupp and Dr. Bohannan to refine the design for the glass corridor, meridian line, and monolith.

Pfeiffer Partners, Inc., formerly the west coast office of Hardy Holzman Pfeiffer Associates (HHPA), is an internationally recognized architectural, planning, and interior design firm with offices in Los Angeles and New York. With a strong focus on creating buildings for public and educational use, including museums, libraries, theaters, and academic facilities, as well as the renovation of historic structures, the firm’s experience includes the award-winning renovation and expansion of the Los Angeles Public Library: Central Library and the new Colburn School of Performing Arts, both in downtown Los Angeles. Pfeiffer Partner’s work with historic structures includes the development of rehabilitation master plans for Los Angeles Union Station and Warner Hollywood Studios, as well as the renovation of seven buildings at Stanford University, including the centerpiece of its historic quad, Memorial Church.

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Davidson Norris

Instrument Architect

Davidson Norris, a practicing architect and co-principle along with James Carpenter of Carpenter Norris Consulting (CNC), designed the Gottlieb Transit Corridor instrument, including the foil, meridian arc, and ecliptic chart. Norris has broad experience in technical analysis of daylighting issues, an important aspect of this outdoor exhibit. CNC has served as daylighting consultants on a wide range of projects from museums (The Guggenheim) to courthouses (the Bronx Criminal Courthouse), office buildings (Hoffman LaRoche Administration Building), convention centers (Austin Convention Center Extension), laboratories (Novartis), and urban parks (Tear Drop Park).

A graduate of the Yale School of Architecture, Norris teaches sustainable design at Columbia School of Architecture and architectural daylighting at Yale and Columbia Schools of Architecture. Norris has received numerous awards for his work, including from the U.S. Department of Energy, the New York Foundation for the Arts, the National Trust for Historic Preservation, and the International Association of Lighting designers.