The answers to the evolution of galaxies are blowing in the solar winds, astronomers say.

Sally Oey, from the Lowell Observatory in Flagstaff, Ariz., gave a talk in which she described how galaxies evolve and are affected by massive stars. The talk was held at Broida Hall on Wednesday and was attended by UCSB astronomers and physicists who discussed topics such as solar wind, metallicity and atomic spectra.

A solar wind is not like an actual breeze, but is a current composed of high-velocity atomic particles. Most of these particles are protons and electrons. The solar wind is the mechanical force that Oey said is partly responsible for galactic evolution. This is similar to how a large cluster of balloons will all drift apart when one balloon in the center of the cluster is popped. The popped balloon produces a sudden gust and mechanically pushes the other balloons apart.

Some stars have a greater influence on their surroundings because they produce more radiation, solar wind or chemical influence, Oey said.

“These are pretty large stars,” Oey said. “They are thought to drive evolutionary activity in galaxies.”

There are about seven general classifications of stars. The hottest stars are blue, with an average surface temperature of about 15,000 Kelvin, or 26,500 degrees Fahrenheit. The brightest star in the constellation Orion is Rigel, a type of blue star. The coolest stars are red, with a surface temperature under 3,500 K (5,800