Frontiers of Astronomy October 15, 2009

Frontiers of Astronomy is a free lecture series that offers those with an interest in astronomy the chance to learn about the latest research in the field.
Presentations are held at The Cleveland Museum of Natural History in Murch Auditorium. No tickets or reservations required.
On clear evenings, the Museum’s Ralph Mueller Observatory will be open afterward.
SCHEDULE:

The Dark Side of the Universe
Dr. Neta Bahcall, Princeton University
Thursday, October 15, 2009, 8 pm

What is the Universe made of? Recent observations suggest surprising new results. Not only is most of the matter in the Universe dark and unconventional but, more surprisingly, the major component of the Universe may be in the form of “dark energy” — a form of energy that opposes the pull of gravity and causes the expansion of the Universe to accelerate. By combining recent observations of clusters of galaxies, distant supernovae and the cosmic microwave background, we find evidence for a Universe that has only 5 percent normal matter, 20 percent dark matter and 75 percent “dark energy.” The observations suggest a Universe that is lightweight, with only 25 percent of the critical mass density needed to halt the Universal expansion, and a geometry that is flat with no space curvature. Dr. Neta Bahcall will discuss observations of the dark side of the Universe and their implications.

Planetary Nebulae and the Galactic Merry-Go-Round
Dr. Robin Ciardullo, The Pennsylvania State University
Thursday, November 12, 2009, 8 pm

Planetary nebulae have nothing to do with planets. They are the stellar equivalent of a heart attack, an event that occurs when a star like the sun dies. They are also some of the most beautiful objects in the Universe, and a “Swiss Army knife” for a host of extragalactic astronomy and cosmology problems. Dr. Robin Ciardullo will describe how planetary nebulae are created, what makes them shine the way they do and how they can be used to weigh galaxies like our own.

A Cosmological Revolution – Notes From The Field
Dr. Julio Navarro, University of Victoria, British Columbia, Canada
Thursday, December 10, 2009, 8 pm

Cosmology — the study of how the Universe began and how its structures formed and evolved — has always been at the frontier of human knowledge, seeding religions, cementing civilizations and challenging scientific thought. It is remarkable that a compelling, empirically verifiable account of the Universe’s history has only emerged during the past few decades. Dr. Julio Navarro will review the observations and theories that have shaped our present cosmological paradigm, the enigmas they have uncovered and what they tell us about the fundamental laws of physics as well as the fate and origin of the Universe.

The Past and Future of the Astrophysical Universe
Dr. Avi Loeb, Harvard University
Thursday, March 18, 2010, 8 pm

The initial conditions of our Universe can be summarized on a single sheet of paper. Yet the Universe is full of complex structures today, such as stars, galaxies and groups of galaxies. Dr. Avi Loeb will describe how complexity emerged in the form of the first stars out of the simple initial state of the Universe at early cosmic times. The future of the Universe is even more surprising. Over the past decade it was realized that the cosmic expansion has been accelerating. If this accelerated expansion will continue into the future then within one hundred billion years there will be no galaxies left for us to observe within the cosmic horizon except one — the merger product between our own Milky Way galaxy and its nearest neighbor, the Andromeda galaxy.

The Great Escape: Hypervelocity Stars
Dr. Juna Kollmeier, Observatories of the Carnegie Institution for Science, Pasadena, California
Thursday, April 15, 2010, 8 pm

The most recently discovered population of stars in the Galaxy are the “Hypervelocity Stars.” These objects are shooting out of the Milky Way at such high speeds they will escape the Galaxy’s gravitational pull and never return. How did they get their enormous velocities? What can we learn about the Milky Way’s dark matter halo, star formation and the supermassive black hole at the galactic center by studying them? Dr. Juna Kollmeier will address these questions and more.

Official Website: http://www.cmnh.org