- 업종: Aerospace
- Number of terms: 16933
- Number of blossaries: 2
- Company Profile:
The Executive Branch agency of the United States government, responsible for the nation's civilian space program and aeronautics and aerospace research.
The point in a planet's orbit in which it is closest to earth. When viewing a planet it will appear on the opposite side of the sky as the sun. Two bodies are in opposition when the difference in celestial longitude is 180 degrees.
Industry:Astronomy
The point of the celestial sphere directly overhead, 90 degrees above the horizon, for any point on earth; it is the point where a plumb line extended upward would intersect the celestial sphere.
Industry:Astronomy
The hypothetical primordial matter, proposed by george gamow, from which the chemical elements may have been formed.
Industry:Astronomy
Very short wavelength radiations beyond the ultraviolet in the spectrum, which are about one ten-thousandth as long as the visible violet and are extremely penetrating.
Industry:Astronomy
The position on the ecliptic occupied by the sun about december 22 when it reaches its greatest southerly declination.
Industry:Astronomy
The position on the celestial sphere occupied by the sun on or about march 21 when its path on the ecliptic crosses the celestial equator going from south to north. This point is also called the march equinox and the first point of aries.
Industry:Astronomy
The invisible electromagnetic radiation beyond the violet end of the spectrum of visible light, of wavelengths ranging, roughly, from 4000 down to 400 angstroms.
Industry:Astronomy
The phase when more than half (but not all) of the planet's side facing earth is illuminated by the sun.
Industry:Astronomy
