The Scientific Context for Exploration of the Moon (2007) / Chapter Skim
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6 Observations and Science Potentially Enabled by the Vision for Space
6 Observations and Science Potentially Enabled by the Vision for Space
Pages 62-73
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From page 62... ...
, through its Radiocommunication Sector, has formally recognized the scientific impor tance of lunar radio astronomy, especially below 30 MHz, in its recommendation ITU-RA.479 "Protection of frequencies for radioastronomical measurements in the shielded zone of the Moon." The committee notes, however, that that the low level of radio interference in this zone could be compromised by noncompliant development on the farside surface, telecommunication and research spacecraft in lunar orbit (including reflections) , or science missions elsewhere, notably at the Earth-Sun Lagrange points.
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From page 63... ...
A low-frequency radio interferometer with simple dipole elements spread out on a kilometer scale of the lunar surface thus has synergistic value to both priority astrophysical and heliophysical research. As a result of this synergy, as well as the usefulness of such low frequencies to understanding particle acceleration mechanisms in active galaxies, a modest nearside array has substantial scientific value both for these bright astronomical sources and also for allowing the refinement of technology and understanding of environmental issues.
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From page 64... ...
Accessibility by humans is not clearly a unique advantage offered by the lunar surface. There is a large base of experience in deploying, maintaining, and servicing large telescopes in free space from the Hubble Space Telescope, as well as substantial expertise in in-space construction of large facilities from the International Space Station experience.
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From page 65... ...
To the extent that such telescopes might someday be considered to be truly viable for priority astronomy, a careful assessment of dust contamination, both from natural processes and from human operations on the surface, will be necessary. Finally, can the very substantial computing requirements of a future array for cosmological studies be credibly powered at a remote lunar site that is unlikely to see continuous solar illumination, especially in view of the fact that the quietest radio-frequency conditions will be at night?
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From page 66... ...
Also needed is long-term characterization of the natural seismic environment, to be complemented by predictions of the induced seismic environment caused by future human lunar operations. A careful assessment of radio noise on the lunar farside, which may see contributions from local electrostatic discharges, is also of importance.
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From page 67... ...
The astrobiological significance of polar samples places a greater emphasis on cryogenic sample return, or alternatively on an appropriately equipped laboratory facility at a polar outpost supported by human fieldwork. In identifying and characterizing extrasolar planets, there is congruence of the objectives of astronomy and astrophysics with those of astrobiology-related observational goals, namely, to maximize the effective aperture of telescopes.
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From page 68... ...
Nonlunar zircons would be geochemically distinctive and, if found, they would provide information about timing, composition, and conditions on their parent body, possibly including the habitability of early Earth. Existing lunar samples might be used to evaluate whether such materials exist in a detectable amount and, if promising, methods could be developed for prospecting likely environments on the Moon and processing large amounts of lunar material to search for unusual components foreign to the Moon that could be returned to Earth for advanced forms of analysis.
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From page 69... ...
Note that observations in the IR are possible from all lunar orbital positions, while observations at visible wavelengths will be somewhat restricted. Examples of possible instruments for observing Earth from the Moon are as follows: • Telescopes as a front end for spectroscopes to provide high spatial resolution imaging, • High-spectral-resolution spectrometers and/or interferometers covering the ultraviolet-visible-infrared spectrum, and • Reference radiometers.
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From page 70... ...
The major components of the observatory are the antenna array and electric connections, the radio receivers, the central processing unit, the high-gain antenna unit, and the power unit. For a test array with 16 to 32 antennas, the expected total mass for a lunar observatory would be significantly less than 400 kg, and the power requirement would be less than 500 W
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From page 71... ...
-Extreme Ultraviolet instrument camera system placed on the lunar surface. SOURCE: Courtesy of Dennis Gallagher, NASA Marshall Space Flight Center.
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From page 72... ...
THE SCIENTIFIC CONTEXT FOR EXPLORATION OF THE MOON Similarly, the low-latitude ionosphere can be imaged from the Moon by detecting the UV emissions of ionospheric ions. Emissions from O+ ions have been used to track the formation and evolution of density troughs associated with the ionospheric spread-F phenomena.
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From page 73... ...
Recommendation 5: The committee recommends that NASA consult scientific experts to evaluate the suit ability of the Moon as an observational site for studies of Earth, heliophysics, astronomy, astrophysics, and astrobiology. Such a study should refer to prior NRC decadal surveys and their established priorities.
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