The Dark Side of the Force
This Wednesday, May 20 Physicist Patricia Burchat of Stanford University will give a non-technical, illustrated talk on The Dark Side of the Universe: Dark Matter and Dark Energy.
Okay, what the heck is this dark matter and energy stuff? Good question. Actually, it is a bit of a mystery to scientists.
Let us tackle Dark Matter. We live in an average galaxy called the Milky Way. The Milky Way contains about 100 billion stars. Yeah, 100 billion stars is an average galaxy. Individual galaxies are concentrated into groups, called clusters of galaxies. Clusters of galaxies are more than just galaxies; the space between galaxies in clusters is filled with hot gasses. These gasses are so hot that they are detected in X-rays and not visible light. Scientists checked out the distribution and temperature of the hot gasses to determine how much total matter there is in that part of space. They discovered that there is five times more material in clusters of galaxies from the galaxies themselves and the hot gasses. Most of the stuff in clusters of galaxies is invisible, scientists thus presume that most of the matter in the entire Universe is invisible. This invisible stuff is called Dark Matter.
Dark Energy is a different story that is not easily explained here. Let us just say that dark energy refers to the fact that some kind of stuff must fill the vast reaches of mostly empty space in the Universe in order to be able to make space accelerate in its expansion.
Dr. Patricia Burchat is Chair of the Physics Department at Stanford University. She studies matter and antimatter created at the Stanford Linear Accelerator Center, also the bending of light by the gravity of massive clusters of galaxies far away.
Seating is on a first-come, first-served basis. Arrive early to locate parking.
Parking lots 1, 7 and 8 provide stair and no-stair access to the Smithwick Theater.
Smithwick Theater, Foothill College
12345 El Monte Road, Los Altos Hills
Wednesday, May 20
7:00 pm
Admission: Free
Parking: $2.00
650-949-7888



This Wednesday, January 21, astronomer Anthony Colaprete of NASA’s Ames Research Center will give a non-technical, illustrated talk on Prospecting for Water on the Moon: The Upcoming LCROSS Mission.

