The facilities of the National Solar Observatory (NSO) are critically important to the solar community, both because few university astronomy departments maintain solar facilities and because NSO telescopes are among the best in the world. Yet budgetary pressures, accumulated over many years, have weakened the NSO. For example, the observatory has been unable to purchase state-of-the-art infrared or visible-light detector arrays to support solar adaptive-optics experiments at an appropriate pace. This situation should be corrected and is one reason that this committee's highest priority for ground-based astronomy is renewed investment in the infrastructure.

Solar neutrino experiments constitute a complementary way of looking inside the sun. The nuclear fusion reactions that cause the sun to shine occur deep within the sun's core but are revealed directly by observations of particles called neutrinos. The United States operates the chlorine solar neutrino experiment, which detects rare high-energy neutrinos of the electron type. The United States also collaborates with the Soviet Union, Germany, France, Italy, and Israel on experiments using gallium detectors to detect electron neutrinos from the basic proton-proton reaction and with Canada and the United Kingdom to construct a detector of heavy water to observe higher-energy neutrinos of all types. In addition, the United States has a potentially important collaboration with Italy and the Soviet Union to observe the beryllium neutrino line with a liquid scintillator. These observatories have complementary functions, including the study of variations of the neutrino flux with phase in the solar cycle.

The Search for Extraterrestrial Intelligence

Ours is the first generation that can realistically hope to detect signals from another civilization in the galaxy. The search for extraterrestrial intelligence (SETI), involves, in part, astronomical techniques and is endorsed by the committee as a significant scientific enterprise. Indeed, the discovery in the last decade of planetary disks, and the continuing discovery of highly complex organic molecules in the interstellar medium, lend even greater scientific support to this enterprise. Discovery of intelligent life beyond the earth would have profound effects for all humanity. NASA's decade-long Microwave Observing Program is based on a particular set of assumptions and techniques for exploring the SETI problem. This committee, like the Field Committee before it, believes strongly that the speculative nature of the subject also demands continued development of innovative technology and algorithms. A strong peer-reviewed, university-based program should be an integral part of this effort.


During the 1980s, the initial reliance on the Space Shuttle for access to space, followed by the Challenger disaster, slowed the rate of progress in U.S.

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