ISSN:0094-243X    

DOI:10.1063/1.39334

出版商:AIP    

年代:1990

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.39335

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

This paper has four major themes: (1) The concept of lunar‐based astronomy should be taken seriously, in part because of important non‐astronomical factors–in particular the many impending drivers of lunar development such as the current and future levels of space technology, the growing recognition of the Moon as probably the next goal for permanent occupation beyond the Space Station, the Moon’s proximity and consequent relevance toward human exploration and moves out into the Solar System, and the possibility of substantial economic return including even tourism in the reasonably foreseable future. (2) The Moon offers a constellation of factors which make it potentially a uniquely effective site for much of the UV/optical/IR observational astronomy of the future. Since these factors form a part of the background of nearly every paper at this workshop, they are collected here and discuss in brief detail. (3) There are several possible approaches to developing lunar astronomy, with extremes which might be calledevolutionary(beginning with small telescopes) andrevolutionary(beginning with gigantic systems). These approaches are briefly discussed and compared, with the suggestion that we work up toward spectacular goals through a substantial series of dedicated smaller instruments, nearly all of which will retain great value even when the giant systems become available–this is the concept of true lunarobservatoriesrather than just several great instruments. It is the lunar counterpart of Explorer, perhaps even Spartan, missions. (4) Finally, the importance and desirability are stressed of international cooperation in these developments over the next several decades.

ISSN:0094-243X    

DOI:10.1063/1.39336

出版商:AIP    

年代:1990

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.39337

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

The moon is an attractive location for astronomical observatories because of the absence of a substantial lunar atmosphere and the stability of the lunar surface. The present lunar atmosphere is sufficiently transparent that there is no significant image distortion due to absorption or refraction. This thin atmosphere results from a combination of small sources and prompt losses. The solar wind is the major source, with a total mass input into the lunar atmosphere of less than 50 gm/sec. The principal atmospheric loss mechanism for most gases is photoionization within a period of weeks to months, followed by immediate loss to the solar wind. Lunar base activities will add gases to the lunar atmosphere by rocket exhaust, processing of lunar materials, venting of pressurized volumes, and astronaut life support systems. Although these sources will substantially exceed natural sources, for modest lunar base activity the effects are expected to be localized and transient and not a significant impediment to lunar based astronomy. The absence of a substantial lunar magnetic field or atmosphere allows solar wind, magnetospheric plasma, and cosmic radiation to penetrate directly to the lunar surface. This ionizing radiation environment creates difficulties for workers and some sensitive instruments, but for certain science investigations (such as neutrino detection) the background environment on the moon is lower than on the earth.

ISSN:0094-243X    

DOI:10.1063/1.39338

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

In the post‐Apollo era, serious studies of lunar‐based observatories began at the first Lunar Bases Symposium held in Washington in 1984. This symposium generated several new and innovative proposals for telescopes on the Moon. Inspired by this first general symposium on lunar‐based activities, a workshop focused specifically on Future Astronomical Observatories on the Moon was held in Houston in 1986. The proceedings from this workshop began to build a case for lunar observatories by describing the considerable attributes of the lunar environment for astronomy. Proposed observatory concepts included x‐ray and gamma‐ray variability monitors, a large aperture optical/IR telescope, Arecibo‐style radio telescopes in lunar craters, and a Moon‐Earth radio interferometer. Studies of two proposed telescopes continued via workshops held in Albuquerque. The first, convened in 1988, was devoted to a Lunar Far‐Side Very Low Frequency Array. The second, held in 1989, was devoted to a long baseline optical‐uv‐IR synthesis array on the lunar surface. The proceedings from these workshops laid the foundation for more detailed investigations of lunar‐based astronomical telescopes.

ISSN:0094-243X    

DOI:10.1063/1.39339

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

This paper discusses site selection criteria for a Moon‐based observatory, using an area on the NE flank of the Orientale Basin at 80° W on the lunar equator as a recommended example. Such a site would provide the following advantages: visibility of essentially the entire celestial sphere, continual line of sight to Earth, dynamic accessibility for minimum energy landings and takeoffs, closeness to the far side for installation of instruments requiring a radio silent environment, trafficable and workable terrain, closeness to geologically important features, and closeness to volcanic features with potential resources. Polar and far side sites have advantages as well, and no one site can meet all requirements. It is suggested that other candidate sites be evaluated by the criteria used for the Orientale Basin.

ISSN:0094-243X    

DOI:10.1063/1.39340

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

This is a report synthesizing discussions of the Astronomy/Astrophysics Definition Team at the Lunar Science Strategy Workshop for the Exploration and Development of the Moon which was held at the NASA Johnson Space Center during August 15‐16, 1989, and was chaired by F. Vilas. Astronomical observatories on the Moon offer the benefits of enormous scientific return and large community interaction. We envision the long‐term goal of lunar based astronomy as the development of a diverse facility covering all wavelengths of the electromagnetic spectrum. This facility will build on and eventually replace the Great Observatories. The development of optical and infrared interferometry should be a principal activity, optimized by a lunar site. However, we believe strongly that lunar observatories should evolve from simple to complex systems and that they should not and need not make major demands on the limited amount of manpower envisioned for the first 20 years of the lunar outpost. We advocate a program in which we build on our lunar experience, initially using small facilities to answer questions critical to the design and construction of larger, more complex systems in the future. At the same time these small initial facilities offer the potential of significant scientific benefits immediately upon our return to the Moon.

ISSN:0094-243X    

DOI:10.1063/1.39341

出版商:AIP    

年代:1990

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.39299

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

The ability to utilize the lunar surface as an observing site presents many opportunities for X‐ray and gamma‐ray astronomy in the early decades of the 21st century. Some of the advantages of a lunar base for certain instruments include the lack of an overlying atmosphere, the availability of stable real estate to establish instruments requiring large structures and long baselines, and ultimately the possibility of manufacturing and assembling extensive modular detection systems. X‐ray astronomy beyond 2010 will require detector systems with high angular resolution, large area collectors for high throughput, X‐ray cameras for all sky monitoring and hard X‐ray telescopes with long focal length, among other capabilities. Systems meeting these requirements which can be appropriately placed on the moon are discussed here. In the gamma‐ray range, the lunar surface seems appropriate for observation of transient phenomena at all wavelengths, high sensitivity spectroscopy of nuclear gamma‐rays, and possibly for implementation of the massive detector systems required for further advances in the 100 MeV, GeV, and TeV energy ranges.

ISSN:0094-243X    

DOI:10.1063/1.39301

出版商:AIP    

年代:1990

数据来源: AIP