Physics and astronomy professor will use telescope attachment to find planets

Natalie Spray

When the light of a distant star beamed into the eyes of 6-year-old Guillermo Gonzalez through his new telescope, his future became crystal clear.

Several decades later, Gonzalez is still looking into the night sky in search of new and distant planets as an assistant professor of physics and astronomy.

“I began as an amateur,” he said.

Gonzalez is building an instrument that will be attached to an existing telescope located in the Erwin Fick Observatory near Boone. The attachment will allow him to search for more planets in the solar system.

“Gonzalez is using a new instrument in a clever way,” said Steven Kawaler, professor of physics and astronomy and program coordinator.

The addition to the telescope is based on a prototype other astronomers have used. It consists of a fiber optic cable that connects the telescope to equipment located in a temperature-controlled room below the telescope.

The cable will feed into a vibration-stabilized table, where the equipment measures velocity changes in the stars’ movement, Gonzalez said.

Planets do not orbit around stars, he explained. Rather, both the star and the planet orbit around a shared center of mass. A star without a planet spins around its own center. The effect of a planet on the rotation of stars, on their velocity, can help astronomers discover planets, he said.

The new equipment will allow Gonzalez to join groups of people all over the world also hoping to discover more planets.

“Many stars need to be surveyed and monitored,” he said, “But only a few telescopes with that capability exist.”

Gonzalez said he hopes to have “first light” about a year from now.

First light is an astronomy term referring to the first time light from a star travels through a telescope, he said.

Kawaler said the telescope addition Gonzalez is creating is a risk because it is expensive, difficult and pushes technological advancements, yet he said he has confidence in Gonzalez.

“Iowa State’s participation [in the search for new planets] is something the university can capitalize on,” he said.

Gonzalez said he has been working with newly discovered planets since 1995. He has studied the spectra, or light, of the star to determine the components, temperature and other characteristics of the planet.

The switch from analyzing stars to searching for planets is a “logical evolution of [Gonzalez’s] research focus,” Kawaler said.

Through his research, Gonzalez said he has discovered stars with planets have different compositions, and two planets have been found based on predictions he has made.

Gonzalez teaches Astronomy 120, which introduces the nonscientist to the sky and solar system; Astronomy 344L, which teaches observational techniques; and Astronomy 510, a graduate-level class that emphasizes projects using telescopes and modern technologies.

“Part of doing research is teaching,” Gonzalez said. “I hope I can contribute something meaningful, new and interesting that won’t quickly be forgotten,” he said.

Gonzalez earned his doctorate degree in astronomy in 1993 from the University of Washington. He has done post-doctoral work at the University of Texas-Austin and the University of Washington-Seattle. Gonzalez came to Iowa State in 2001.