Astonomy Club talks black holes

The Leisure World Astronomy Club will meet on Dec. 8 at 7 p.m. in Clubhouse 3, Room 3. On the agenda are discussions of the club’s officers and bylaws, as well as a telescope inventory. The group will also view a 30-minute video titled “Black Holes Explained, Part 1: General Introduction to Black Holes,” by Dr. Alex Filippenko. A question-and-answer session, plus a discussion on escape velocity, will follow.

Black holes are regions of space in which gravity is so strong that nothing, not even light, can escape. References to black holes abound in popular culture, but few truly understand what they are. They are far from being the figments of the fertile imaginations of theoretical physicists and science-fiction writers, as observational evidence for the presence of black holes is now quite compelling.

Filippenko begins his video with a broad overview of black holes, explaining some of the main concepts and defining terms. Newtonian plausibility arguments for the existence of what was then called “dark stars” were first made several centuries ago, but a complete understanding requires Einstein’s general theory of relativity and the realization that matter warps both space and time.

All who are interested are invited; if viewing conditions are favorable, the evening will conclude with a star party featuring two or more telescopes. Everyone is welcome to bring telescopes and/or binoculars.

—John Rogers