An OU physics professor will give a free lecture discussing how scientists measure the age of galaxies using elements present in stars.

John Cowan is a physics professor who studies radioactive elements in stars. His lecture, “The Age of the Milky Way,” is scheduled from 7 to 8 p.m. Friday in the Sam Noble Oklahoma Museum of Natural History.

The method Cowan uses to determine the galaxy’s age relies on very good telescopes and strong nuclear physics, he said.

For this reason, much of his research has been on hold while the Hubble Telescope is worked on, he said.

Although the universe is constantly expanding, scientists believe that most galaxies are actually about the same age, Cowan said.

Scientists believe the universe is about 14 billion years old, and most galaxies were created within the first billion years of existence, he said.

There are no new galaxies, and many stars are slowly running out of gas, Cowan said.

“It’s going to take billions of years but [the universe] is slowly dying,” he said.

Henry said previous lectures filled up quickly and he recommends people show up 20-30 minutes early.

The lecture series is sponsored by the OU physics and astronomy department, the Sam Noble Museum, Norman schools, Oklahoma City Astronomy Club, Odyssey Astronomy Club, Ten Acre Observatory, Astronomics, Inc. and R.A. Graphix.

The lecture is a part of the International Year of Astronomy series celebrating the 400th anniversary of Galileo’s invention of the telescope.

Amateur astronomers will have telescopes set up outside for viewing the night sky following the lecture, physics professor Richard Henry said.

A raffle will also be held for a pair of astronomical binoculars donated by Astronomics.

For more information visit http://www.nhn.ou.edu/iya09.