papers published in each subfield has not changed dramatically, and the fraction of astronomers employed at universities, colleges, government labs, and FFRDCs has not changed significantly. The committee was surprised by the tremendous continuity of the field.
Over the past 12 years there has been a dramatic growth in the fraction of journal publications funded by foreign agencies and written by foreign authors. This growth parallels the flourishing of Japanese and European astronomy. The Europeans and the Japanese have built several major observatories, including the European Very Large Telescope (VLT) and Subaru, and have launched several cutting-edge satellites. While American astronomy benefits from collaboration on foreign-led joint missions such as ROSAT, ASCA, and ISO, the U.S. effort will have to keep pace with this overseas growth if the United States is to maintain our world leadership role in astronomy.
The construction of large ground-based optical telescopes, primarily via private funds, has resulted in a large gap in the funding of the design, development, operation, and construction of instrumentation for these facilities. The 1995 NRC report A Strategy for Ground-Based Optical and Infrared Astronomy recommended a vigorous facility instrumentation program. This need continues.
While NASA has always funded the analysis and interpretation of data obtained from space, NSF has not provided the necessary funds for this activity for ground-based astronomy. The fraction of NSF proposals that are funded has been dropping steadily and is now near 28 percent. Thus, while ground-based astronomers have excellent and increasing access to new telescopes, they often lack the funds for computers, travel, theoretical precursor and follow-on studies, and postdoctoral fellows to take proper advantage of this access. Increases in NASA observing grants have taken up some of the shortfall for general support but only indirectly address the problem. One possible solution is to adopt an approach similar to NASA's and identify in advance of the construction of telescopes and instruments the resources necessary to utilize them fully, including funds for theory and facility instruments. The recent wave of construction of new large telescopes summarized in Table 5.13 has been financed largely by private donations. Although NSF has no specific obligation to support the instrumentation of these new private facilities, the committee calls attention to the vulnerability of the U.S. research effort and leadership in ground-based astronomy if adequate funding for these instruments, whatever the source, is not raised and reemphasizes the findings of the NRC report A Strategy for Ground-Based Optical and Infrared Astronomy.
The U.S. program in astronomy and astrophysics would be severely affected by the catastrophic failure of one of its premier observational facilities such as HST or Chandra. The consequences of a failure of HST, the current worst-case scenario in astronomy, are examined briefly here, and similar ramifications of the failure of Chandra are noted.
Construction of HST began in 1977. Although it has been refurbished three times since being placed in orbit in 1990, many of its basic components date to the late 1970s. As HST continues to age, the chances for catastrophic failure increase. The recent failure of one of HST 's remaining gyroscopes is an example. Each HST space shuttle servicing mission is a risky operation. Although we all hope that HST can be operated to 2010, we must be prepared for an earlier failure.