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PCS Earth Science
Chapter 27 Vocabulary - The Sun-Earth-Moon System
Term | Definition |
---|---|
albedo | amount of sunlight that is reflected by the surface of a planet or a satellite, such as the moon |
highland | light-colored, mountainous, heavily cratered areas of the moon, composed mostly of lunar breccias |
mare | dark-colored, basaltic, smooth plain on the moon, between 3.1 and 3.8 billion years old, that formed from lava welling up and filling in large impact basins |
impact crater | moon crater formed when space material impacted on the lunar surface |
ejecta | material that falls back to the lunar surface after being blasted out by the impact of a space oject |
ray | long trail of ejecta that radiates outward from a moon crater |
rille | valley like structure that meanders across some regions of the moon's mara |
regolith | layer of loose, ground-up rock on the lunar surface |
ecliptic | plane that contains Earth's orbit around the sun |
summer solstice | occurs when the sun is directly overheard at 23.5 degree north latitude, around June 21, and results in the maximum number of daylight hours for the northern hemisphere and the minimum number for the southern hemisphere |
winter solstice | occurs when the sun is directly overhead at 23.5 degree south latitude, around December 21, and results in the minimum number of daylight hours for the northern hemisphere and the maximum number for the southern hemisphere |
autumnal equinox | occurs when the sun is directly overhead at the equator and results in day and night of equal length for both northern and southern hemispheres |
vernal equinox | occurs when the sun is directly overhead at the equator and results in day and night of equal length for both northern and southern hemispheres |
synchronous rotation | describes the state at which the moon's orbital and rotational periods are equal |
solar eclipse | occurs when the moon passes between earth and the sun and the moon casts a shadow on Earth, blocking Earth's view of the sun; can be partial or total |
perigee | closest point in the moon's elliptical orbit to earth. |
apogee | farthest point in the moon's elliptical orbit to earth. |
lunar eclipse | occurs only during a full moon, when earth passes between the sun and the moon, and earth's shadow falls on the moon |
refracting telescope | use lenses to bring visible light to a focus |
reflecting telescope | bring visible light to a focus with mirrors |
interferometry | the process of linking separate telescopes together so that they act as one telescope |
spinoffs | NASA technologies that have been passed on to commercial industries for common use |