I switched off the ignition, collected my notebook and a ballpoint pen, and stepped out of the car into the implacable Southern California sun. It took a moment for my eyes to adjust: The sun and the concrete of the parking structure had conspired to create a sort of washed-out effect. As I gathered my bearings visually, I became aware of a sound, a persistent creaking coming from the far corner of the structure. The sound grew in both intensity and frequency. I had come to Los Angeles – specifically, to Exposition Park, where I had just exited my car – to visit the California Science Center, a hands-on museum for families and a provider of educational and professional development programs. As I approached the main building of the center, I encountered the source of the creaking: a giant lever with a 5400-lb pickup truck suspended from one end and three knotted ropes from the other. Kids were jumping on and off the ropes – labeled “Effort ×1,” “Effort ×2” and “Effort ×4” – with varying degrees of success in lifting the truck off the ground, ever so slightly. Their father was recording their attempts with a video phone and trying to provide some guidance (“No, no, the far rope! The far rope!!!”); their mother was reading aloud from a placard explaining how levers work. The kids were clearly enjoying themselves and, not incidentally, discovering important physical principles. And we were still in the parking lot. Informal learning, interactive worlds The California Science Center’s mission is to stimulate curiosity and inspire people – young and old alike – to learn about science, by creating “fun, memorable experiences.” Like many of the more than 15,000 “informal learning” institutions in the US, it seeks to educate people by engaging them in the process of discovery, to encourage them to ask questions and understand “the why.” The California Science Center in Los Angeles offers a panoply of hands-on exhibits that encourage guests to experiment, and to ask questions about how – and why – things work. By involving them in the discovery process, the center, and many other such “informal learning” institutions, hopes to inspire guests to learn more. Paula Browne Wagner, associate director of communications, greeted me when I finally tore myself away from the giant lever in the parking lot. After giving me a helpful overview of the museum and its many offerings, she took me upstairs to see the “Light Table” exhibit, part of the communications section of the Creative World gallery. This gallery examines “the built world,” she explained – specifically, communications, structure and transportation. The Light Table was designed to demonstrate the many ways in which light can be directed, its path altered. Scattered about the exhibit was an assortment of filters, fiber optics, prisms, lens and mirrors that guests could use to explore the possibilities – reflecting, bending and absorbing the light. Kids gathered around and played with these as I talked with Doug Upshaw, a volunteer presenter positioned next to the exhibit. Children of all ages like to experiment with the optics, he told me. Some simply enjoy seeing how they can divert the light with the devices they find on the table; others approach him with questions about how the devices work and why the light does what it does. Does this depend on their age? “Not always,” he said. “In fact, you’d be surprised at the questions some of the younger ones come up with.” Later, Paula and I ventured over to the Amgen Center for Science Learning – the education arm of the California Science Center – in one of the neighboring buildings. Educational outreach and development is part of the science center’s mission and encompasses a host of programs. Anna Gaiter, director of professional development, walked me through a number of these – including parent and teacher workshops and GEMS (Great Exploration in Math and Science) modules, all designed to introduce a sense of discovery to the learning process. They do impressive work at the center. I thanked Paula and Anna and promised to call to talk more about the benefits of incorporating such programs into public school curricula (see “The Value of Discovery” in the October issue of Photonics Spectra). “… Bang! Zoom! Straight to the moon!” That same evening, after grabbing a bite to eat on the unfashionable end of Sunset Boulevard, I drove to Griffith Observatory, nestled high in the Hollywood Hills. It was July 16, the 40th anniversary of the Apollo 11 moon shot, and the observatory was hosting various events commemorating its launch. In particular, I was planning to attend a talk by David Reitzel, Griffith’s astronomical lecturer, titled, “The Moon Landings: Hoax or No Hoax?” * The talk was fun, designed to reach people of all ages, it seemed. First, Reitzel explained why it would have been very, very difficult – if not impossible – to pull off such a hoax. For example, tens of thousands of engineers were involved in the design of the rockets and shuttle that delivered the astronauts to the moon. Surely, one of them would have spoken up by now if they knew the landings hadn’t worked. Never mind the Russians, who tracked the missions independently. Then he showed footage of the lunar rovers kicking up dust as they rumbled across the surface, and of the US flag waving in an unlikely manner, and noted how aspects of the footage reflected the unique atmosphere and gravity of the moon. Ultimately, the landings would have been “way too hard to fake,” he said. “It would have been easier just to go to the moon.” Gary Boas firstname.lastname@example.org * This wasn’t an optics event, per se, but I did happen to sit next to a very nice woman from the NASA Jet Propulsion Laboratory, who told me about some of the optics used in the Mars missions.