THE CYRIL PONNAMPERUMA LECTURE

OVERVIEW OF COSMIC EVOLUTION

George V. Coyne, S.J.
Specola Vaticana,
Citta' del Vaticano
00120 Roma, Italy.
FAX: (06) 6988 4671
email : gcoyne@specola.va

ABSTRACT
The most significant fields in the study of cosmic evolution extend over a wide range of topics including the physics of the early universe to the search for extra-solar planetary systems. In this overview I wish to emphasize two general conclusions which can be drawn from the most recent research: (1) public opinion to the contrary, our scientific knowledge of the universe is very limited; (2) there is increasing evidence that we may not be alone in the universe.

(1) By combining elementary particle physics with quantum cosmological models we have a solid understanding of the very early universe. Less well known are the epochs of the formation of structure in the universe: galaxies and clusters of galaxies. The deep field observations with the Hubble Space Telescope challenge all theories accepted to date for the development of structure. A principal difficulty is that the observations indicate that structure developed much earlier than can be accounted for in any of the expanding universe cosmologies. The detection of non-homogeneity challenges inflationary models. Despite intense efforts to determine the ultimate fate of the universe, we are more confused than ever by the discovering that the universe at large distances is accelerating. More than a decade of attempts to identify the dark matter in the universe have left us still in doubt, although the observational evidence for its existence is overwhelming.

(2) We must be very careful in our formulation of the extra-terrestrial life debate. The question to be addressed is not whether there is extraterrestrial intelligence, since there is no scientific data whereby to even approach an answer. The question is rather: Are there the physical conditions for Earthlike life elsewhere in the universe? In other words, is there any evidence that there are planets like the Earth about stars like the Sun with the macrophysical conditions for life? Research over about the past decade has led to the discovery of more than one hundred planets about other stars. These planets have been discovered by analyzing the systematic oscillations in the motion of the parent star. Only massive planets near to their parent star can be discovered in this way. Other techniques, such as high-resolution imaging in space and from the Earth, spectroscopic detection of extra-solar planetary atmospheres. etc, are being developed. Much progress is being made in the search by spectroscopy for biotic or pre-biotic conditions in extra-solar planets. Within the next decade we will undoubtedly discover hundreds more extra-solar planets. It appears, therefore, from an observational point of view, that the existence of planetary systems is a not uncommon phenomena. Do any of them nurture the physical conditions for life?

THE PUBLIC LECTURE

EUROPA: OVERVIEW OF FUTURE MISSIONS

Torrence JOHNSON
Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena CA 91109, USA

ABSTRACT
There is significant evidence from the Galileo exploration of the Jupiter system, and other planetary studies, that the icy moons of Jupiter, Europa, Ganymede, and Callisto, have global, liquid water oceans beneath their icy crusts. These environments are critical targets for exploration related to the origin and evolution of life outside the Earth. The key ingredients for support and possibly for the origin of life as we know it ­ liquid water, organic molecules, and energy ­ are probably available in varying degrees on each of these bodies. Europa is particularly interesting since on this moon a global water ocean about 100 km deep may overlie a rocky, silicate mantle heated by both radioactive decay and tidal energy, raising the possibility of environments similar in many ways to terrestrial seafloor hydrothermal systems.

The US National Academy of Sciences' National Research Council has recently completed a survey of solar system exploration in the coming decade. Their recommendations include a very high priority for future exploration of Europa with a 'flagship' class Geophysical Explorer mission as well as increased emphasis on the other icy moons that may harbor sub-surface oceans. NASA has responded with a proposal for a Jupiter Icy Moon Orbiter mission that would send a spacecraft with a sophisticated payload to the Jupiter system, capable of going into orbit around each of the icy moons and conducting detailed scientific investigations. The mission concept involves use of electric powered ion-drive (pioneered for deep space use by NASA's Deep Space 1 mission) propulsion system powered by a small, highly efficient nuclear reactor. Launched with a conventional heavy-lift rocket, the spacecraft's power system would not be activated until after orbit has been achieved.

Studies of the JIMO mission are now underway, including detailed definition of the science objectives by a Science Definition Team. Based on a competitive selection within the next two years, the science investigations are expected to include geodetic and geophysical studies of the tides raised by Jupiter, induced and intrinsic magnetic fields, detailed geologic and geochemical mapping of the surfaces at high spatial resolution, studies of the interactions of the satellites with the Jupiter magnetosphere as well as studies of the Jupiter system as whole.

THE CLOSING LECTURE

THE NEW UNIVERSE, DESTINY OF LIFE AND CULTURAL IMPLICATIONS

Steven J. Dick,
US Naval Observatory,
3450 Massachussetts Av.
NW, Washington, DC 20392-5420
United States of America

ABSTRACT
I intend to have a double thrust, both in the context of cosmic evolution:
1) that if cosmic evolution commonly ends in life and intelligence, this "biological universe" has many implications for our terrestrial culture(s), which I will address, and 2) that we need to take more seriously the cultural evolution component of cosmic evolution. On Earth cultural evolution totally dominates biological evolution, and in a universe where civilizations may be billions of years old, cultural evolution may have led to a "postbiological universe", dominated by artificial intelligence, with great implications for SETI. I will argue that we need to take a long-term "Stapledonian" view of cultural evolution in the universe.