Learn what astronomers mean when they use terms like “dark matter” and “dark energy” at a free lecture to be held on the University of Missouri-Rolla campus.

Dr. Robert A. Knop Jr., assistant professor of physics and astronomy at Vanderbilt University, will speak on “The Power of the Dark Side: the Exotic Material that Makes Up Most of Our Universe” in a UMR Harlow Shapley Lecture at 7:30 p.m. Thursday, April 5, in Room 104 Physics Bldg. The lecture is free and open to the public.

Knop’s research focuses on galaxy formation, evolution and interactions, and cosmology. From 1996 to 2005, he was a member of the Supernova Cosmology Project, one of the two research teams that discovered the acceleration of the universe’s expansion – a discovery that was credited as the 1998 “Discovery of the Year” by Science Magazine. A portion of Thursday’s lecture will focus on the implications of this discovery.

In the past decade there has been a renaissance in cosmology, the area of astronomy that focuses on the evolution of the universe, explains Knop, and astronomers finally have a consistent and complete picture of the constituents of the universe.

“Unfortunately,” says Knop, “95 percent of the density of the universe is made up of stuff that astronomers don’t fully understand.”

In his lecture, Knop will describe what astronomers mean when they use the terms “dark matter” and “dark energy” and he will describe the line of evidence that led them to conclude that those are the things that make up most of the universe.

The Harlow Shapley lecture is sponsored by the American Astronomical Society, the Harlow Shapley Visiting Lectureship Endowment Fund and the UMR physics department. For more information about the lecture, call 573-341-4409 or email Dr. Gerald Wilemski, professor of physics at UMR, at wilemski@mst.edu.