The National Aeronautics and Space Administration is pleased to invite you to a series of three lectures “From our Earth to other earths”

March 21, 2002

Earth’s Climate System: A 21st Century Grand Challenge

Dr. Bruce A. Wielicki, NASA Langley Research Center

April 4, 2002

Evolution in Space

Dr. Kenneth Kosik, Harvard Medical School

April 18, 2002

The Search for Life Beyond the Solar System

Dr. Charles Beichman, Jet Propulsion Laboratory

All lectures will be from 6:30 to 7:30 PM at the

Carnegie Institute of Washington
1530 P Street NW
Washington, DCÊ 20005

There is a wonderful exhibition celebrating the Carnegie’s
100th Anniversary titled “Our Expanding Universe”.Ê
The exhibition is open until 8:00 PM.

NASA Lecture:

Earth’s Climate System: A 21st Century Grand Challenge

Dr. Bruce A. Wielicki, NASA Langley Research Center

March 21, 2002

Understanding and ultimately predicting the Earth’s climate system is one of the grand challenges of the 21st century.Ê As scientists delve deeper into its complexity, mysteries continue to arise at a rate faster than new answers.Ê The water and energy cycles in particular couple complex physics that varies from scales as small as an aerosol particle 0.1 micron across to tropical circulation patterns covering half the globe: a daunting 14 orders of magnitude. These huge changes in scale are more normally associated with studies of astronomy.Ê But unlike astronomy, complex non-linear interactions occur at all space and time scales between the tinyÊ aerosol particle and the huge tropical Hadley cell.Ê This daunting complexity challenges our attempts to model and predict future climate change here on Earth.Ê Yet ironically, while weather prediction is known to be impossible with any skill past 14 days, decadal climate change may ultimately be predictable with very high accuracy.Ê Where are we in meeting this climate prediction challenge?Ê Dr. Wielicki will present a brief summary of climate modeling and of NASA global satellite observations used to test climate models.Ê Recent results from the dramatic 1998 El Nino and a 20-year tropical climate change record will be used to highlight the challenges being faced in one of the most uncertain aspects of climate prediction: how clouds will respond to climate change.Ê Some future strategies for improved climate data and climate prediction models will be suggested.Ê

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Dr. Bruce A. Wielicki is the Senior Scientist for Radiation Science at the NASA Langley Research Center.Ê He currently leads NASA’s Earth Observing System satellite mission to measure the radiative energy balance of the Earth in support of global climate research efforts.Ê This radiative energy balance drives the ocean and atmospheric dynamics and is at the heart of understanding the still uncertain roles of aerosols and clouds in the climate system.Ê Dr. Wielicki has led research on clouds and the Earth’s radiative energy balance for over 20 years, ranging from theoretical modeling to global satellite observations.Ê He has received the NASA Medal for Exceptional Scientific Achievement as well as the American Meteorological Society Henry G. Houghton Award.


Evolution in Space: A Key Ingredient for Sustaining a Long-term Presence away from Planet Earth

Dr. Kenneth Kosik, Harvard Medical School

April 4, 2002

Life is the delicate machinery that confers on organisms a replicative capacity to create succeeding generations for the near future, and the potential to evolve for the distant future. Without the ability to evolve, species would become extinct and the planet would turn lifeless.Ê Evolution arises from the dynamic interplay between nearly random errors that creep into our genes from time to time and the selection among these errors for those rare mutations which actually enhance reproductive fitness.Ê One crucial engine of selection is the environment because mutations that might go unnoticed in one setting, can enhance survival in another.Ê The entry of an organism into a novel environment triggers a selection process that leads, over many generations, to the radiation or fanning out of new lifeforms in a seemingly inexhaustible throng of creative solutions for reproductive success.Ê Space represents a novel environment and we must be prepared–even pave the way–for the biological changes in organisms which will inevitably occur over many generations away from the earth.Ê In fact, without evolutionary change life will never take root in space.Ê The hostility of the extra-terrestrial environment demands that we find biological solutions to a host of problems such as micro-gravity, cosmic radiation, even the ordeal of our own psyches spent in long periods of isolation.Ê In the evolutionary process lies a means to a solution.Ê But what is the path ahead?Ê We must begin now to catch a glimpse of how evolution will deal with the challenge of space, how small changes in master genes will give rise to organisms that are highly fit for passing a lifetime in space.Ê Our most pressing need toward the goal of inhabiting space for long durations either on space station or on a trip to Mars is to begin a space colony in which organisms can reproduce over many generations and point the way toward fundamental biological solutions for survival.Ê Needed on board are a variety of genetically diverse organisms upon which the process of natural selection can act.

Kenneth S. Kosik, M.DÊ is a Professor of Neurology and Neuroscience at the Harvard Medical School.Ê He is also a staff neurologist at Brigham and Women’s Hospital, the major teaching hospital affiliate of the Harvard Medical School, where he was one of the founding physicians of the Memory Disorders Clinic. Dr. Kosik directs the Cellular Neurobiology Laboratory at Brigham and Women’s Hospital where he is working on the molecular basis of brain plasticity.Ê He received his M.D. degree in 1976 from the Medical College of Pennsylvania. He directed a project as principal investigator on the Neurolab NASA mission and was a recipient of the NASA Group Achievement Award to the Neurolab Science Team.Ê He has authored over 150 research publications including journal articles, book chapters, and invited reviews.

The Search for Life Beyond the Solar System

Dr. Charles Beichman, Jet Propulsion Laboratory

April 18, 2002

The last five years have seen a breakthrough in the centuries-long quest to find other solar systems with the discovery of more than gas giant planets orbiting some 75 nearby stars.Ê But what are the prospects for findingÊ Earth-like planets, and ultimately evidence of life itself, in other solar systems? Dr. Charles Beichman will address the question of life beyond the solar systemÊ from a variety of perspectives: the formation and evolution of planetary systems, the interaction between a planet and its atmosphere, the origin of life, and the implications of finding life beyond Earth.Ê It is a startling fact that we will soon have within our grasp the technology needed to find and characterize terrestrial planets around starsÊ tens of light years away.Ê The philosophical question of “Other Worlds” has become susceptible to scientific investigation.

Dr. Charles Beichman is the Chief Scientist for Astronomy and Physics at the Jet Propulsion Laboratory (JPL).Ê His scientific interests are in the areas of star and planet formation. He leadsÊ a team of researchers who will use the Space Interferometer Mission (SIM) to study the evolution of planetary systems around newly formed stars and is the project scientist for the Terrestrial Planet Finder (TPF),Ê a proposed NASA mission to search for habitable, Earth-like planets orbiting nearby stars.