Scientific Opportunities in the Human Exploration of Space (1994) / Chapter Skim
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3 SCIENCE ENABLED BY HUMAN EXPLORATION
3 SCIENCE ENABLED BY HUMAN EXPLORATION
Pages 17-29
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From page 17... ...
Additional scientific opportunities arise in the study of the physiological response of living organisms to microgravity and fractional gravity environments and in studies of human behavior during protracted sequestration and other stressful situations. Moreover, technology developed for a human exploration program may enable unrelated robotic .
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From page 18... ...
The discussion of the advantages of human presence in planetary exploration is not theoretical: it has been demonstrated on the Apollo lunar missions.) Twelve astronauts, in six missions of increasing complexity, conducted tasks ranging from surface sample collection, with associated observations and photographic documentation of the geological context, to drilling and coring of the regolith, to emplacement of geophysical instruments.
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From page 19... ...
Second, study of the incipient growth of regolith on fresh bedrock surfaces on the Moon (for example, melt sheets of large fresh craters) would provide data for making inferences about stages of early growth exposed in regolith-bedrock contacts elsewhere on the Moon.3 4 Both of these studies require detailed field work, not only to collect samples intelligently, but also to make the observations and synthesize the visual clues needed to understand regolith growth dynamics.
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From page 20... ...
Site selection will require subjective decisions based on astute observations of the specific locale, probably requiring a trained field observer. Additionally, access to important sites may require the versatility of human workers.
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From page 21... ...
The sophistication of the analytical methods and the variability of sample types that must be anticipated weigh against full automation of such analyses in the foreseeable future; human field workers/laboratory technicians will be required. On the other hand, this required analytical sophistication and complexity could argue for continued sample return.
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From page 22... ...
Layered deposits visible in the polar ice caps may have preserved a unique record of climate swings that occurred over the last few hundred million years.~° Portions of this record may be recovered by drilling into the "sediments" and ice and analyzing the core samples. The two major causes of climate variations are thought to be martian orbital effects and temporal changes in solar irradiance.
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From page 23... ...
Although the lunar surface is a good place to study the solar wind's long-term, integrated composition, experience from the Apollo program shows that local magnetic fields complicate and invalidate the study of any short-term variations from the lunar surface. Although much was learned about the solar wind from analysis of samples collected in aluminum foils deployed by the
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From page 24... ...
The European Space Agency's recent Phase-1 study of science on and from the Moon also found specific opportunities for astronomical observations, especially interferometry. However, it too urged a conservative approach and recommended a set of further studies.~9 CHEX endorses the findings of the Astronomy and Astrophysics Survey Committee report on the next decade in astronomy,20 which called for an evolutionary approach to lunar astronomy, one that complements the Earth-orbiting and ground-based astronomy program.
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From page 25... ...
The emissions can, however, be imaged using "pinhole-camera methods" such as coded aperture masks and pairs of parallel-slit grids, which produce a Moire fringe pattern in the detector plane.30 The requirement for a sufficiently large field of view sets lower limits on the characteristic dimension of the apertures (be they pinholes or slits) , and in turn the angular resolution requirement sets a lower limit to the separation of the grid pairs or masks.
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From page 26... ...
Thus it is not yet possible to predict how prolonged exposure to near-zero or fractional gravity will alter living systems. However, sufficient information is available to know that the absence of normal gravity profoundly alters living systems; thus exploration missions to the Moon and Mars will offer additional opportunity beyond Earth-orbiting space stations, to investigate the fundamental biological processes by which gravity affects living organisms.3i Missions to the Moon and Mars will also provide an opportunity for behavioral studies on crews under highly stressful conditions as well as over prolonged periods of time in close confinement.
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From page 27... ...
An advanced propulsion system is required to send a spacecraft 250 astronomical units from the Sun in significantly less than the 25 years or more required by conventional propulsion aided by gravity assists. Once such an advanced propulsion system is available, it could also be used for other high-energy missions, such as to propel instruments to large distances above the solar poles or into a short-period, circular solar polar orbit, and, perhaps, even a short-period eccentric orbit that skims through the solar corona at altitudes as low as three solar radii.35 SCIENTIFIC COMMUNITY PARTICIPATION CHEX has given considered thought to how space science might benefit from the existence of a program of human exploration of the Moon and Mars, undertaken primarily for reasons other than science.
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From page 28... ...
2. NASA, A Planetary Science Strategy for the Moon, JSC-25920, Lunar Exploration Science Working Group, Johnson Space Center, Houston, Texas, July 1992.
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From page 29... ...
30. Paul Gorenstein, "High-Energy Astronomy from a Lunar Base," Future Astronomical Observatories on the Moon, NASA Conference Publication 2489, NASA, Washington, D.C., 1988, page 45.
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