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The activities of the Commission have continued to focus on controlling unwanted light and radio emissions at observatory sites, monitoring of conditions at observatory sites, and education and outreach. Commission members have been active in securing new legislation in several locations to further the protection of observatory sites as well as in the international regulation of the use of the radio spectrum and the protection of radio astronomical observations.
Astrobiology's goal of promoting interdisciplinary research is an attempt to reverse a trend that began two centuries ago with the formation of the first specialized scientific disciplines. We have examined this era of discipline formation in order to make a comparison with the situation today in astrobiology. Will astrobiology remain interdisciplinary or is it becoming yet another specialty?
As a case study, we have investigated effects on the scientific literature when a specialized community is formed by analyzing the citations within papers published during 1802–1856 in Philosophical Transactions of the Royal Society (Phil. Trans.), the most important ‘generalist’ journal of its day, and Transactions of the Geological Society of London (Trans. Geol. Soc.), the first important disciplinary journal in the sciences. We find that these two journals rarely cited each other, and papers published in Trans. Geol. Soc. cited fewer interdisciplinary sources than did geology papers in Phil. Trans. After geology had become established as a successful specialized discipline, geologists returned to publishing papers in Phil. Trans., but they wrote in the new, highly specialized style developed in Trans. Geol. Soc. They had succeeded in not only creating a new scientific discipline, but also a new way of doing science with its own modes of research and communication.
A similar citation analysis was applied to papers published over the period 2001–2008 in the contemporary journals Astrobiology and the International Journal of Astrobiology to test the hypothesis that astrobiologists are in the early stages of creating their own specialized community. Although still too early to reliably detect any but the largest trends, there is no evidence yet that astrobiologists are drifting into their own isolated discipline. Instead, to date they appear to remain interdisciplinary.
Astrobiology involves the study of the origin and history of life on Earth, planets and moons where life may have arisen, and the search for extraterrestrial life. It combines the sciences of biology, chemistry, palaeontology, geology, planetary physics and astronomy. This textbook brings together world experts in each of these disciplines to provide the most comprehensive coverage of the field currently available. Topics cover the origin and evolution of life on Earth, the geological, physical and chemical conditions in which life might arise and the detection of extraterrestrial life on other planets and moons. The book also covers the history of our ideas on extraterrestrial life and the origin of life, as well as the ethical, philosophical and educational issues raised by astrobiology. Written to be accessible to students from diverse backgrounds, this text will be welcomed by advanced undergraduates and graduates who are taking astrobiology courses.
The core questions of astrobiology are not new. They have always been asked and are central to Western intellectual history. How did life begin? How has it changed? What is the relation of humans to other species? Does life exist elsewhere? If so, where might it be and what is it like? Although these questions are ancient, what is new are the tools at hand to search for answers, ranging from robotic spacecraft to genome sequencing, from electron microscopes to radio telescopes. These tools and other factors (see the Prologue and Chapter 2) appear to have brought astrobiology to a point where it is gelling into something qualitatively different – our first sound attack on these questions. But is this so? Or is today no different from any other time in the past few centuries?
In every era, including our own, scientists can do no more than tackle questions with the best tools available, apply the best insight they can muster, and struggle to fashion a consensus as to the nature of the world. In this manner our understanding has progressed, for example, from the “animalcules” that van Leeuwenhoek described three hundred years ago to the richness of contemporary microbiology. To understand such a thread as it meanders through history, we need to document more than the accumulation of facts. When evaluating a given episode, historians of science look carefully at evidence of not only the science itself, but also of the larger enveloping context.
In order to compete successfully in the marketplace of the radio spectrum radio astronomers must appeal not to economic gain, but to the cultural value of their enterprise. In the real world this can be problematic, but it is not hopeless. This paper gives arguments why radio astronomy, no less than astronomy as a whole, has great cultural value whether considered from an environmental or an intellectual point of view.
We are now developing an innovative SETI project, tentatively named seti@home, involving massively parallel computation on desktop computers scattered around the world. The public will be uniquely involved in a real scientific project. Individuals will download a Screensaver program that will not only provide the usual attractive graphics when their computer is idle, but will also perform sophisticated analysis of SETI data using the host computer. The data are tapped off Project Serendip IV’s receiver and SETI survey operating on the 305-meter diameter Arecibo radio telescope. We make a continuous tape-recording of a 2 MHz bandwidth signal centered on the 21 cm H I line. The data on these tapes are then preliminarily screened and parceled out by a server that supplies small chunks of data (50 sec of 20 kHz bandwidth, a total of 0.25 MB) over the Internet to clients possessing the screen-saver software. After the client computer has automatically analyzed a complete chunk of data (in a much more detailed manner than Serendip normally does) a report on the best candidate signals is sent back to the server, whereupon a new chunk of data is sent out. If 50,000-100,000 customers can be achieved, the computing power will be equivalent to a substantial fraction of a typical supercomputer, and seti@home will cover a comparable volume of parameter space to that of Serendip IV.
Two important episodes in the early development of interferometry in radio astronomy are traced in detail. The first is the use of the sea-cliff interferometer at the Radiophysics Laboratory in Sydney, first by Pawsey for solar observations and later by Bolton for radio star surveys. The second is the development of the Michelson interferometer and the phase switch by Ryle in Cambridge. This also was employed for important observations of the sun and radio stars.
An image of the entire earth at nighttime is assembled for the first time. It consists of a mosaic of photographs, all taken at local midnight in the 400-1100 nm band, made by the Defense Meteorological Satellite Program over the period 1974-84. Photographs were selected for freedom from clouds, lack of moonlight, high sensitivity, and suitability to illustrate various temporal phenomena. The image primarily reveals activities of humankind such as urban street lighting, rangeland burning, slash-and-burn agriculture, natural gas burnoffs in oilfields, and squidding. Although light pollution in urban areas creates a striking map, at the same time it devastates astronomical observation and removes much of humankind from any familiarity with the night sky.