This result, first suggested by observations of supernova explosions in distant galaxies, has been confirmed during the past year by an entirely different set of observations of the unevenness in the cosmic background radiation. Come with us on a tour of cosmological thought and observation and hear Dr. Goldsmith give his best explanation of what we currently believe, and why, about the mighty cosmos in which we live. Born in Washington, D.C. in 1943 where his parents were both economists for the government, he graduated from Harvard College in 1963 and then received his Ph.D. in Astronomy from U.C. Berkeley, where he later became a professor. He is the award-winning author of The Ultimate Einstein, The Hunt for Life on Mars, and The Astronomers. Dr. Goldsmith also authored the book, Voyage to the Milky Way, and he served as a consultant for the video of the same title.
Gravity can bend light.
Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218. The cluster is so massive and so compact that its gravity bends and focuses the light from galaxies that lie behind it. As a result, multiple images of these background galaxies are distorted into faint stretched out arcs - a simple lensing effect, similar to looking through a glass of wine. The Abell 2218 cluster itself is about 3 billion light-years away in the northern constellation Draco. I thought I might tap into his encyclopedic knowledge of solar system observations by asking if he'd ever heard of anyone looking for ashen light during a lunar occultation of Venus.