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Appendix B Glossary, Acronyms, and Abbreviations
Pages 88-91

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From page 88...
... B Glossary, Acronyms, and Abbreviations ALSEP -- Apollo Lunar Surface Experiments Package anorthosite -- a type of rock made up mainly of plagioclase feldspar, which has been found in all the Apollo lunar samples and constitutes most of the light-colored crust on the Moon Archaea -- a recently recognized domain of prokaryotic life. Single-celled microorganisms that lack a nucleus, are morphologically similar to bacteria but not closely related, having features such as genetic transcription and translation that are different.
From page 89...
...  APPENDIX B chondrite -- a type of stony meteorite containing chondrules, roughly spherical bodies containing pyroxene or olivine embedded in the matrix chronostratigraphy -- the branch of stratigraphy that studies the absolute age of rocks cool early Earth -- hypothesis that the surface of Earth cooled relatively quickly after the formation of the core and the Moon, such that oceans and conditions hospitable for life could exist by 4.3 Ga Copernican -- the lunar geologic period from about 1.1 Ga ago to the present Cretaceous/Tertiary boundary -- on Earth, the boundary between rocks of the Cretaceous and Tertiary periods, about 65.5 million years ago, around the time of a major extinction event cumulates -- igneous rocks formed by the accumulation of crystals from a magma detrital zircons -- zircon crystals found in erosional deposits. Some grains are as old as 4.4 Ga and are the oldest known samples of Earth differentiated planetary body -- a planetary body whose interior is formed of separate internal geologic units with distinct mineralogical characteristics, e.g., core, mantle, crust Erastosthenian -- the lunar geologic period from 1.1 Ga to 3.2 Ga ago ESMD -- NASA's Exploration Systems Mission Directorate EVA -- extravehicular activity Exosphere -- the highest layer of an atmosphere feldspathic -- pertaining to rocks rich in feldspar minerals Ga -- one billion years geochronology -- determination of the time at which a rock crystallized, usually by radioactive decay of parentdaughter isotope pairs: U-Pb, Sm-Nd, K-Ar, or Rb-Sr hyperthermophile -- microorganisms that live in hot environments, above 60°C igneous rocks -- rocks crystallized from a magma ISRU -- in situ resource utilization Isua greenstone rocks -- a geological formation in southwestern Greenland (Isua)
From page 90...
... This event is proposed to have limited the emergence of life on Earth LCROSS -- the Lunar Crater Observation and Sensing Satellite, a secondary payload to be launched with the Lunar Reconnaissance Orbiter LEAG -- the NASA Lunar Exploration Analysis Group (LEAG) is responsible for analyzing scientific, technical, commercial, and operational issues associated with lunar exploration LPRP -- the Lunar Precursor and Robotic Program of the Exploration Systems Mission Directorate LRO -- NASA's Lunar Reconnaissance Orbiter LSAM -- NASA's Lunar Surface Access Module Lunar A -- a Japanese Aerospace Exploration Agency lunar mission lunar dynamo -- for the ancient Moon, the possibility that a lunar magnetic field might have been generated by the internal motion of an iron-rich molten core Lunar Magma Ocean hypothesis -- the hypothesis that when the Moon formed, it was molten to a depth of hundreds of kilometers; its crystallization produced the primary crust and mantle mafic materials -- a dark-colored, igneous rocks rich in ferromagnesian minerals magma -- molten rock from the interior of a planetary body mantle -- the geologic zone above the core and below the crust MER -- NASA's Mars Exploration Rover obliquity -- the angle between the orbital plane of an object and the plane of its rotational equator olivine -- a magnesium iron silicate mineral (FeMg)
From page 91...
...  APPENDIX B protolith -- the original rocks from which igneous, metamorphic, or sedimentary rocks were formed pyroclastic -- a type of rock material formed by volcanic explosion pyroxene -- a group of common ferromagnesian rock-forming minerals regolith -- on the Moon, the surface rock debris that overlies bedrock remanent magnetization -- also called paleomagnetism, the component of a rock's magnetism that has a fixed direction and is independent of Earth's magnetic field rheology -- the study of the deformation and flow of matter SBE -- surface boundary exosphere SELENE -- Selenological and Engineering Explorer, a Japanese Aerospace Exploration Agency lunar orbiter SIM -- the Apollo Scientific Instrument Module, which contained panoramic and mapping cameras, a gammaray spectrometer, a laser altimeter, and a mass spectrometer SIMS -- secondary-ion mass spectrometry SMART-1 -- Small Missions for Advanced Research in Technology, a European Space Agency lunar mission SMD -- NASA's Science Mission Directorate SPA -- the lunar South Pole-Aitken Basin stratigraphy -- the study of rock layers TEM -- transmission electron microscopy U-Pb geochronology -- the determination of the age of a rock based on radioactive decay of isotopes of U and Th to Pb, usually in the mineral zircon VSE -- NASA's Vision for Space Exploration xenolith -- a foreign inclusion in an igneous rock zircon -- a silicate mineral (ZrSiO4)

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