A program to measure the night sky brightness has been in progress for some years in order to calibrate the extent of the night sky brightness surrounding the Van Vleck Observatory. Both the central intensity and the areal extent of the brightest sky caused by campus and city were repeatedly measured in order to gauge the extent of the problem. For this purpose, portable visual photometers were designed which have remained stable and usable for nearly a decade. They are now useful for the measurement of the effects of increases in urban growth and of the more flexible attitude of the campus administration toward excess campus lighting. The inability to define city populations which realistically model and predict the measured sky brightness is the largest source of uncertainty. The observatory is in the Northeastern Corridor where the observed brightness is the sum of the illumination from a number of overlapping city sources. Present light pollution studies have not correctly defined the model for the population of an urban area. The two paradigmatic definitions now available for use are shown to be flawed for light pollution comparisons. An algorithm, unlike any in present use, must be sought which distinguishes between individual core cities within metropolitan areas.

Light trespass is a real problem to astronomers, and, to some extent, to the general public. There is really no valid excuse for most of our existing light trespass. If we were all aware of the problems, we could rather easily implement solutions to cure the problems.

Little attention has been directed toward the environmental and economic costs of light pollution. We estimate that 2.5 percent of the total United States electricity production is expended on nighttime outdoor lighting. About 30 percent of all outdoor nighttime lighting ends up in the night sky. This is equivalent to 17.4 billion kilowatt-hours of electricity, more than the individual electrical production of many countries, including Chile, Cuba, Hungary, Ireland, Indonesia, Israel, Libya, Peru, Syria, or Vietnam. About one half of light pollution arises from direct upward lighting and one half from reflections off the ground and buildings. Light pollution directly costs the country at least a billion dollars a year in unnecessary electricity charges, in addition to the associated environmental harm from the mining and burning of fossil fuels to generate this wasted electricity. The equivalent of 8.2 million tons of coal (or 30 million barrels of oil) are burned annually in the United States simply to light up the night sky. The proper use of full cut-off shielding, timers, and appropriate light levels, if widely instituted, could reduce the overall urban sky glow by at least a factor of four in the next few decades.

Kalispell, Montana, a city of about 20,000 near the Canadian border, has completed major relighting. Aging mercury vapor lamps along U.S. routes #2 and #93 nave been replaced with low pressure sodium (LPS) fixtures. The downtown also has LPS plus turn-of-the-century style cast iron lampposts with low wattage fluorescent lamps, which provide white light on storefronts and curbside parking. The Chamber of Commerce helped with the purchase of these fixtures, which are lit from dusk to midnight and, in the winter, from 6:00 A.M. until sunrise. Most other areas of Kalispell are lit with high pressure sodium in full cut-off fixtures. City and county officials have calculated that the payback time for the LPS relighting was 40 months.

Photographs taken during a clear, moonless night from the walkway of the dome of the Canada-France-Hawaii Telescope on Mauna Kea show light trespass from street lighting in Hilo and in Waimea and the sky glow from the growing area around Kona. More full cut-off fixtures would help to prevent deterioration of the quality of the Mauna Kea site.

We have detected a component of sky brightness varying with a frequency of 120 Hertz during high speed photometric observations of 40 Eridani with the 30-cm telescope of the University of British Columbia. The observations were made in 1974, but only recently has their significance to the field of urban illumination been realized. The 120 Hertz component was detected by Fourier analysis of data sets of the star and of the sky alone. We confirmed that the 120 Hertz component was due to urban lighting by direct observation of a “standard source,” a lamp on the campus.

In 1980, the City of Portland began a conversion project to change out all existing mercury vapor street lights to high pressure sodium. During the planning and design portion of the project, the City hired a consulting firm to look at our existing system and make recommendations as to light source and fixture configuration. After some on site studies of existing street lighting, it was recommended that all arterial streets of the City of Portland be converted from mercury vapor to high pressure cut-off fixtures, in order to cut down glare in the eyes of drivers. Secondly, it was recommended that, on arterial streets, the City could no longer afford to light “key-hole to key-hole.” It was important to confine the light to the street right-of-way.

Until the last century, virtually all humans knew the appearance of the dark night sky. Even unschooled urbanites knew some constellations and planets. By 1909, light pollution made authors admonish readers to do their skywatching from the countryside rather than the city. The warnings have escalated along with the light pollution. Light pollution’s effect on professional and volunteer observational astronomy, along with telescopes’ changing focal ratios, largely determine which kinds of astronomy are done in which institutions. In times and places where individuals perceive little possibility to change their culture, astronomers cope as best they can. When activism earns results in other cultural matters, astronomers sometimes become activists to fight light pollution. Chabot Observatory has felt many of these influences in its 105-year history, and they can be read in its plans for the future as well. Despite winning some battles, the war against light pollution is still being lost, so a different approach is suggested.

With the growing expansion of urban areas and their associated “domes” of artificial illumination, amateur astronomers have been forced to change many of their observing habits. This is reflected in the instruments today’s amateurs are using: highly portable telescopes of mostly commercial origin. Amateurs must travel further into the field to find dark skies, and this makes the hobby more discouraging. By discouraging the amateurs, an important education resource is lost to the public.

The International Dark-Sky Association, Inc. (or IDA, Inc.) is a new tax-exempt, non-profit corporation formed to serve the public and the amateur and professional astronomer communities by providing information, education, and research on light pollution and related topics. IDA will share knowledge of the issue on a local, national, and international basis and will assist with members’ problems. It was organized for the purpose of preserving dark skies for astronomy and for the general public. Solutions to the problem of light pollution will, at the same time, also promote maximum effectiveness for all outdoor lighting and will conserve natural resources.

The amount of man-made debris in orbit is now sufficient to create a flux in some regions of low Earth orbit which exceeds the flux of natural meteoroids. The primary source for this debris is from the fragmentation, or disintegration, of spacecraft. Future debris can be expected to result from random collisions between orbiting objects. This debris will require additional shielding for some spacecraft, will contaminate some types of meteoroid experiments, and contaminate some types of astronomical observations. Steps are being taken to minimize the accumulation of future debris.

Astronomical research continues to use ground-based facilities as a principal means of gathering data. The optical light buckets which are trained each night on celestial sources have historically had to just contend with natural interference. Sunlight, moonlight, clouds, debris created by volcanic eruptions, atmospheric seeing, and aurora are examples of factors which modify the interception and analysis of energy radiated in the optical spectrum and received at the collector end. In the last 5 years the “unnatural” encounters with artificial earth satellites are making themselves more pronounced and have become the subject of this limited study.

Some recent images taken by the white light coronagraph telescope aboard the Solar Maximum Mission (SMM) observatory show bright streaks that are apparently caused by particles associated with the spacecraft. In this report we describe these observations, and we analyze the times of their occurrence. We demonstrate that the sightings occur most often near SMM’s orbital dawn, and we speculate that thermal shock is the mechanism that produces the particles. Although these sightings have not seriously affected the coronagraph’s scientific operations, the unexpected passage of bright material through the field of view of sensitive spaceborne telescopes can lead to data loss or, in some cases, serious detector damage. The topic of space debris has become a significant concern for designers of both manned and unmanned orbiting platforms. The returned samples from the SMM spacecraft and the observations reported here provide a baseline of experience for future orbital platforms that plan long duration missions.

The Light Ring, proposed as a celebration of the centenary of the Eiffel Tower, and now withdrawn by its sponsors, demonstrated the feasibility to launch relatively inexpensive satellites which subtend an appreciable solid angle as seen from earth. Other satellites in the competition organized by the Eiffel Tower proposed configurations under the name of Space Art which could unacceptably increase the night sky background. Satellites of this nature, launched for noble but essentially frivolous motives, pose a threat to optical astronomy.

Artworks will be built in space as the frequency and range of space missions increase. Artists have proposed artworks to be installed in space and have worked with space agencies to begin planning for such projects; a few space art projects have been completed. It is argued that artworks should be reviewed with the same constraints as all other space artifacts. It is unlikely that artworks will ever pose the kind of environmental threat that already exists from scientific, commercial and military activities; the cultural value of creating some space art balances the associated costs and risks. Artworks visible to global audiences can be conceived and have been proposed; it is these proposals that have concerned astronomers. Public space art should be subject to a process of public scrutiny similar to that of earth-based public art works. Most space art will involve interdisciplinary teams of artists, scientists and engineers; these projects offer the possibility of artists providing novel ideas and approaches that will be of interest in other applications. Artists in the past have played crucial roles in promoting space exploration, in literature, film and the plastic arts. They have also explored the negative aspects and risks. In the future it is inevitable and desirable that artmaking be included in planned space activities.

Optical observations of near Earth and deep-space debris conducted at M.I.T.’s artificial satellite observatory will be discussed. A brief review of observing technique, regions of high debris density, and amount of debris in orbit will be given. The unique, duplex facilities of the observatory allow the discrimination of debris from meteors, the construction of an orbital element set, and real-time identification of cataloged artificial satellites. Near-Earth debris is present in large numbers in all the popular near-Earth orbits; at least 5-6 times the 5000-6000 objects in the NORAD catalog. In deep-space, the new presence of Ariane-related debris adds significantly to the existing population which is treble that cataloged by NORAD.

The task of avoiding collisions between orbiting objects requires more than a statistical description of the objects’ positions. The paper describes the general procedures used for such cataloging, together with an indication of the accuracy required for orbital collision avoidance.

Radars of various configurations are used to detect the flux of meteors into the atmosphere, and therefore may be of use in characterizing the artificial meteors produced by small (100 microns - 1 cm) pieces of space debris upon re-entry. Both conventional and over-the-horizon radars are discussed here, and the ways in which they may be deployed in order to detect infalling space debris are outlined.

In the United States, civil common carrier telecommunications are provided by private companies, not by any agency of the government. Regulation of these services and spectrum management oversight is provided by the Federal Communications Commission (FCC), an agency of the government. Government telecommunications are operated by individual agencies, e.g. the Department of Defense, under the overall regulation of the Office of Spectrum Management of the National Telecommunications and Information Administration (NTIA), a government body separate from the FCC. In bands shared by the civil and government sectors, liaison and coordination is effected between the FCC and the NTIA.

Today, I would like to discuss with you the history of the National Radio Quiet Zone, the regulation procedures for fixed radio transmitters inside the NRQZ and the RFI environment at the National Radio Astronomy Observatory (NRAO) site in Green Bank, West Virginia.