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Frontiers of Astronomy
Frontiers of Astronomy is a free lecture series that offers those with an interest in astronomy the chance to learn about some of the latest research in the field.
Presentations are given in the Museum's Murch Auditorium. On clear evenings, the Ralph Mueller Observatory will be open afterward.
Frontiers of Astronomy is sponsored by the Department of Astronomy at Case Western Reserve University through the support of the Arthur S. Holden, Sr. Endowment; The Cleveland Museum of Natural History; and The Cleveland Astronomical Society.
Please note: No tickets or reservations are required.
2007-2008 Lectures
Exploding Stars and the Accelerating Cosmos: A Blunder Undone
Dr. Robert Kirshner, Harvard University
October 18, 2007, 8 pm
Recent observations of exploding stars located halfway across the Universe reveal an astonishing fact: The expansion of the Universe is speeding up! This suggests that empty space itself is the source of a mysterious "dark energy" that drives cosmic acceleration. Curiously, when Albert Einstein first thought about the role of gravity acting throughout the Universe in 1917, he imagined a repulsive "cosmological constant" that would balance out the attractive effects of gravitation. After the expansion of our Universe was clearly established by astronomers, Einstein regarded this cosmological term as a mistake. Modern observations show that we need something that acts very much like Einstein's discarded cosmological constant to account for an accelerating Universe. And we need a lot of it -- dark energy accounts for 70 percent of the Universe today. Dr. Robert Kirshner explains how astronomers use supernova explosions to trace cosmic history and sketches some of the plans to learn more about the nature of the dark energy.
More about Dr. Kirshner:
Robert P. Kirshner is Harvard College Professor of Astronomy and Clowes Professor of Science at Harvard University. The author of over 200 scientific publications, Kirshner has also written for a broader public in National Geographic, Sky & Telescope, Natural History and Scientific American magazines and is a frequent public speaker on science. His award-winning popular-level book The Extravagant Universe: Exploding Stars, Dark Energy, and the Accelerating Cosmos is now in paperback from Princeton University Press and has been translated into four languages. At Harvard, Kirshner teaches a large undergraduate course for students who are not concentrating in the sciences called “The Energetic Universe.” Kirshner is a member of the American Academy of Arts and Sciences, the National Academy of Sciences and the American Philosophical Society. He has just finished a term as President of the American Astronomical Society. In September 2007, Kirshner and his colleagues of the High-Z Supernova Team (including many of his former students and postdocs) shared the Gruber Prize in Cosmology.
Numerical Cosmology: Building the Universe on a Computer
Dr. Romeel Davé, University of Arizona
November 15, 2007, 8 pm
Rapidly advancing surveys of galaxies and intergalactic gas across cosmic time are strenuously challenging theoretical models for explaining the evolution of visible matter in the Universe. Dr. Romeel Davé describes how numerical cosmologists are attempting to meet this challenge by using powerful supercomputers to model the cosmos, and everything in it, from the Big Bang until today. This approach has yielded many insights and successes, but some quite basic properties of galaxies remain poorly understood. The key missing ingredient is a detailed understanding of how galaxies and intergalactic gas are connected as part of a cosmic ecosystem within which galaxies grow and evolve.
More about Dr. Davé:
Romeel Davé received his A.B. (Physics) from UC Berkeley in 1989, M.S. (Physics) from Caltech in 1991 and a Ph.D. (Astrophysics) from UC Santa Cruz in 1998. He went to Princeton as a Spitzer postdoctoral fellow, then to Arizona as a Hubble fellow, and since 2003 has been on the faculty at Arizona. His overarching scientific interest is to understand why the Universe looks the way it does. So far, he has found this problem to be pretty much as perplexing as it sounds.
Dr. Gus Evrard, University of Michigan
December 13, 2007, 8 pm
The Earth and Sun are situa |