SANTA CRUZ — Hopping on a bumper car and setting the GPS destination to outer space, "Toy Story" character Buzz Lightyear would have been thrilled by a scene at the Santa Cruz Beach Boardwalk.
A Science Channel TV crew and UCSC Astronomy Professor Greg Laughlin were equally excited Friday morning, using the Speed Bump ride as a visual analogy to illustrate the concept of gravity assist in outer space.
The crew approached Laughlin and the Santa Cruz Boardwalk to shoot an episode of "Through the Wormhole." Hosted by Morgan Freeman, the series explores scientific questions. The episode "Can we outlive the sun?" is expected to air in the show's fourth season in 2013.
"In billions of years, the sun will get so bright and luminous that life on Earth will be in big trouble," Laughlin said.
To preserve life forms, humans would have to find a way for Earth to move away from the sun by expanding the orbit, Laughlin said.
That's where asteroids, gravity and the Boardwalk's bumper cars come in.
"You could cause our planet to slowly expand its orbit by having asteroids flying by the Earth hundreds of thousands of times," Laughlin said. "This is what I'm showing when I'm driving around our little Earth with my magnet."
Using a metal reproduction of the Earth, a yellow beach ball for the sun and a red magnet, Laughlin and camera operators rode bumper cars, circling their miniature solar system to mimic asteroids.
In real space, this merry-go-round action produces a double effect, Laughlin explained. Because of gravity, the mass of the asteroid entering in our orbit produces a force that slightly pulls the Earth forward, causing our planet to expand the trajectory of its orbit. Simultaneously, gravity forces the asteroid to deviate from its trajectory while gaining speed. This latter phenomenon, used by scientists as a "gravity assist" to speed spacecrafts, is ultimately the most interesting part, Laughlin said.
"Whether we can outlive the sun is the last thing we need to worry about. We don't have the technology to control asteroids and this won't be an issue before a billion years," Laughlin said. "It's a just a dramatic way of showing how gravity assist works."
NASA sent its spacecraft New Horizons in Jupiter's orbit and it gave it a huge boost on its trip to Pluto, Laughlin said. "That will enable us to discover how Pluto looks like years ahead of schedule."
The Boardwalk provided the shooting location to tackle the complex matter, Georgalis said. The director said he is comfortable working with Laughlin, who often pushes TV crews to shoot in Santa Cruz. In 2009, the scientist brought the crew to the Boardwalk for a History Channel piece on Jupiter's chemical activity.
"Santa Cruz is a great town for filming opportunities: we have the ocean, the Boardwalk, the redwood forests," Laughlin said. "If people see the show and want to come visit Santa Cruz as result, that means I've done my job."
<span class='infoBox'><hr> Airs Wednesdays
·"Through the Wormhole" airs at 10 p.m. Wednesdays through Aug. 8 on the Science Channel. For information, see http://science.discovery.com/tv/through-the-wormhole.