July Regular Meeting at SLAS
July 20, 2007 at 7:30 pm
McDonnell Hall, Washington University
Comets: Ancient Messengers
Dr. Erika Gibb
Department of Physics and Astronomy
University of Missouri - St. Louis
Dr. Gibb will talk about both historical and modern observations of comets, concentrating
on the exciting results of recent studies. Comets are rock-and-ice bodies, born
as the earth and the other planets formed, about 4.6 billion years ago. Most
comets reside far beyond the orbit of Pluto, but some are pulled by gravity into
the inner solar system. Those that venture within the orbit of Jupiter develop
the very long, ultra-thin tails that make them such spectacular objects in the
night sky. Comets may hold clues to the formation of the planets and perhaps
even the origin of life on Earth. Recent spacecraft missions have provided close-up
views of the cores of comets. One spacecraft even returned to earth some dust
from a comet. In addition to describing the nature and origin of comets, Dr.
Gibb will also discuss some unanswered questions in comet science, and indicate
how scientists will try to resolve them.
Erika Gibb is an Assistant Professor
of Physics and Astronomy at the University of Missouri, Saint Louis. Her
research interests involve astrochemistry and astrobiology.
Her observational research includes studies with the giant Keck telescopes
in Hawaii of gas and dust disks surrounding young stars. She also investigates
nature and evolution of the enormous interstellar clouds of dust and gas from
which new stars will form. She is particularly interested in the formation
of complex organic molecules within these clouds and disks, and of
the role these
molecules play in the origin of life ? on Earth and perhaps elsewhere.